The amount of radiation energy that is deposited in a unit mass of material, such as tissues of plants or animal. In RADIOTHERAPY, radiation dosage is expressed in gray units (Gy). In RADIOLOGIC HEALTH, the dosage is expressed by the product of absorbed dose (Gy) and quality factor (a function of linear energy transfer), and is called radiation dose equivalent in sievert units (Sv).
Samarium. An element of the rare earth family of metals. It has the atomic symbol Sm, atomic number 62, and atomic weight 150.36. The oxide is used in the control rods of some nuclear reactors.
The relationship between the dose of administered radiation and the response of the organism or tissue to the radiation.
ELECTROMAGNETIC RADIATION or particle radiation (high energy ELEMENTARY PARTICLES) capable of directly or indirectly producing IONS in its passage through matter. The wavelengths of ionizing electromagnetic radiation are equal to or smaller than those of short (far) ultraviolet radiation and include gamma and X-rays.
Harmful effects of non-experimental exposure to ionizing or non-ionizing radiation in VERTEBRATES.
The ability of some cells or tissues to survive lethal doses of IONIZING RADIATION. Tolerance depends on the species, cell type, and physical and chemical variables, including RADIATION-PROTECTIVE AGENTS and RADIATION-SENSITIZING AGENTS.
Emission or propagation of acoustic waves (SOUND), ELECTROMAGNETIC ENERGY waves (such as LIGHT; RADIO WAVES; GAMMA RAYS; or X-RAYS), or a stream of subatomic particles (such as ELECTRONS; NEUTRONS; PROTONS; or ALPHA PARTICLES).
The observation, either continuously or at intervals, of the levels of radiation in a given area, generally for the purpose of assuring that they have not exceeded prescribed amounts or, in case of radiation already present in the area, assuring that the levels have returned to those meeting acceptable safety standards.
A subspecialty of medical oncology and radiology concerned with the radiotherapy of cancer.
The number of copies of a given gene present in the cell of an organism. An increase in gene dosage (by GENE DUPLICATION for example) can result in higher levels of gene product formation. GENE DOSAGE COMPENSATION mechanisms result in adjustments to the level GENE EXPRESSION when there are changes or differences in gene dosage.
Genetic mechanisms that allow GENES to be expressed at a similar level irrespective of their GENE DOSAGE. This term is usually used in discussing genes that lie on the SEX CHROMOSOMES. Because the sex chromosomes are only partially homologous, there is a different copy number, i.e., dosage, of these genes in males vs. females. In DROSOPHILA, dosage compensation is accomplished by hypertranscription of genes located on the X CHROMOSOME. In mammals, dosage compensation of X chromosome genes is accomplished by random X CHROMOSOME INACTIVATION of one of the two X chromosomes in the female.
High-energy radiation or particles from extraterrestrial space that strike the earth, its atmosphere, or spacecraft and may create secondary radiation as a result of collisions with the atmosphere or spacecraft.
Experimentally produced harmful effects of ionizing or non-ionizing RADIATION in CHORDATA animals.
Inflammation of the lung due to harmful effects of ionizing or non-ionizing radiation.
Penetrating, high-energy electromagnetic radiation emitted from atomic nuclei during NUCLEAR DECAY. The range of wavelengths of emitted radiation is between 0.1 - 100 pm which overlaps the shorter, more energetic hard X-RAYS wavelengths. The distinction between gamma rays and X-rays is based on their radiation source.
Tumors, cancer or other neoplasms produced by exposure to ionizing or non-ionizing radiation.
Radiation from sources other than the source of interest. It is due to cosmic rays and natural radioactivity in the environment.
The use of IONIZING RADIATION to treat malignant NEOPLASMS and some benign conditions.
Completed forms of the pharmaceutical preparation in which prescribed doses of medication are included. They are designed to resist action by gastric fluids, prevent vomiting and nausea, reduce or alleviate the undesirable taste and smells associated with oral administration, achieve a high concentration of drug at target site, or produce a delayed or long-acting drug effect.
The total amount of radiation absorbed by tissues as a result of radiotherapy.
The measurement of radiation by photography, as in x-ray film and film badge, by Geiger-Mueller tube, and by SCINTILLATION COUNTING.
That portion of the electromagnetic spectrum immediately below the visible range and extending into the x-ray frequencies. The longer wavelengths (near-UV or biotic or vital rays) are necessary for the endogenous synthesis of vitamin D and are also called antirachitic rays; the shorter, ionizing wavelengths (far-UV or abiotic or extravital rays) are viricidal, bactericidal, mutagenic, and carcinogenic and are used as disinfectants.
The effects of ionizing and nonionizing radiation upon living organisms, organs and tissues, and their constituents, and upon physiologic processes. It includes the effect of irradiation on food, drugs, and chemicals.
The treatment of a disease or condition by several different means simultaneously or sequentially. Chemoimmunotherapy, RADIOIMMUNOTHERAPY, chemoradiotherapy, cryochemotherapy, and SALVAGE THERAPY are seen most frequently, but their combinations with each other and surgery are also used.
Drugs used to potentiate the effectiveness of radiation therapy in destroying unwanted cells.
Drugs used to protect against ionizing radiation. They are usually of interest for use in radiation therapy but have been considered for other, e.g. military, purposes.
A condition caused by a brief whole body exposure to more than one sievert dose equivalent of radiation. Acute radiation syndrome is initially characterized by ANOREXIA; NAUSEA; VOMITING; but can progress to hematological, gastrointestinal, neurological, pulmonary, and other major organ dysfunction.
Unstable isotopes of cobalt that decay or disintegrate emitting radiation. Co atoms with atomic weights of 54-64, except 59, are radioactive cobalt isotopes.
Uncontrolled release of radioactive material from its containment. This either threatens to, or does, cause exposure to a radioactive hazard. Such an incident may occur accidentally or deliberately.
A malignant skin neoplasm that seldom metastasizes but has potentialities for local invasion and destruction. Clinically it is divided into types: nodular, cicatricial, morphaic, and erythematoid (pagetoid). They develop on hair-bearing skin, most commonly on sun-exposed areas. Approximately 85% are found on the head and neck area and the remaining 15% on the trunk and limbs. (From DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1471)
Tumors or cancer of the SKIN.
Computer-based systems for use in personnel management in a facility, e.g., distribution of caregivers with relation to patient needs.
A province of Canada lying between the provinces of Manitoba and Quebec. Its capital is Toronto. It takes its name from Lake Ontario which is said to represent the Iroquois oniatariio, beautiful lake. (From Webster's New Geographical Dictionary, 1988, p892 & Room, Brewer's Dictionary of Names, 1992, p391)
Any type of variation in the appearance of energy output of the sun. (NASA Thesaurus, 1994)
The fourth planet in order from the sun. Its two natural satellites are Deimos and Phobos. It is one of the four inner or terrestrial planets of the solar system.
Travel beyond the earth's atmosphere.
A method for ordering genetic loci along CHROMOSOMES. The method involves fusing irradiated donor cells with host cells from another species. Following cell fusion, fragments of DNA from the irradiated cells become integrated into the chromosomes of the host cells. Molecular probing of DNA obtained from the fused cells is used to determine if two or more genetic loci are located within the same fragment of donor cell DNA.
Any method used for determining the location of and relative distances between genes on a chromosome.
In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
A plant genus of the family POACEAE that is the source of EDIBLE GRAIN. A hybrid with rye (SECALE CEREALE) is called TRITICALE. The seed is ground into FLOUR and used to make BREAD, and is the source of WHEAT GERM AGGLUTININS.
A type of chromosomal aberration involving DNA BREAKS. Chromosome breakage can result in CHROMOSOMAL TRANSLOCATION; CHROMOSOME INVERSION; or SEQUENCE DELETION.
A phenotypically recognizable genetic trait which can be used to identify a genetic locus, a linkage group, or a recombination event.
Any cell, other than a ZYGOTE, that contains elements (such as NUCLEI and CYTOPLASM) from two or more different cells, usually produced by artificial CELL FUSION.
A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.
Men and women working in the provision of health services, whether as individual practitioners or employees of health institutions and programs, whether or not professionally trained, and whether or not subject to public regulation. (From A Discursive Dictionary of Health Care, 1976)
An agency of the PUBLIC HEALTH SERVICE concerned with the overall planning, promoting, and administering of programs pertaining to maintaining standards of quality of foods, drugs, therapeutic devices, etc.
The study of the origin, nature, properties, and actions of drugs and their effects on living organisms.
Disorders that result from the intended use of PHARMACEUTICAL PREPARATIONS. Included in this heading are a broad variety of chemically-induced adverse conditions due to toxicity, DRUG INTERACTIONS, and metabolic effects of pharmaceuticals.
The branch of pharmacology that deals directly with the effectiveness and safety of drugs in humans.
Attitudes of personnel toward their patients, other professionals, toward the medical care system, etc.

Synthesis and evaluation of [18F]1-amino-3-fluorocyclobutane-1-carboxylic acid to image brain tumors. (1/3048)

We have developed a new tumor-avid amino acid, 1-amino-3-fluorocyclobutane-1-carboxylic acid (FACBC), labeled with 18F for nuclear medicine imaging. METHODS: [18F]FACBC was prepared with high specific activity (no carrier added [NCA]) and was evaluated for its potential in tumor localization. A comparative study was performed for [18F]FACBC and [18F]2-fluorodeoxyglucose (FDG) in which the uptake of each agent in 9L gliosarcoma (implanted intracerebrally in Fisher 344 rats) was measured. In addition, the first human PET study of [18F]FACBC was performed on a patient with residual glioblastoma multiforme. Quantitative brain images of the patient were obtained by using a Siemens 921 47-slice PET imaging system. RESULTS: In the rat brain, the initial level of radioactivity accumulation after injection of [18F]FACBC was low (0.11 percentage injected dose per gram [%ID/g]) at 5 min and increased slightly to 0.26 %ID/g at 60 min. The tumor uptake exhibited a maximum at 60 min (1.72 %ID/g), resulting in a tumor-to-brain ratio increase of 5.58 at 5 min to 6.61 at 60 min. In the patient, the uptake of [18F]FACBC in the tumor exhibited a maximum concentration of 146 nCi/mL at 35 min after injection. The uptake of radioactivity in the normal brain tissue was low, 21 nCi/mL at 15 min after injection, and gradually increased to 29 nCi/mL at 60 min after injection. The ratio of tumor to normal tissue was 6 at 20 min after injection. The [18F]FACBC PET scan showed intense uptake in the left frontal region of the brain. CONCLUSION: The amino acid FACBC can be radiofluorinated for clinical use. [18F]FACBC is a potential PET tracer for tumor imaging.  (+info)

MIRD pamphlet no. 16: Techniques for quantitative radiopharmaceutical biodistribution data acquisition and analysis for use in human radiation dose estimates. (2/3048)

This report describes recommended techniques for radiopharmaceutical biodistribution data acquisition and analysis in human subjects to estimate radiation absorbed dose using the Medical Internal Radiation Dose (MIRD) schema. The document has been prepared in a format to address two audiences: individuals with a primary interest in designing clinical trials who are not experts in dosimetry and individuals with extensive experience with dosimetry-based protocols and calculational methodology. For the first group, the general concepts involved in biodistribution data acquisition are presented, with guidance provided for the number of measurements (data points) required. For those with expertise in dosimetry, highlighted sections, examples and appendices have been included to provide calculational details, as well as references, for the techniques involved. This document is intended also to serve as a guide for the investigator in choosing the appropriate methodologies when acquiring and preparing product data for review by national regulatory agencies. The emphasis is on planar imaging techniques commonly available in most nuclear medicine departments and laboratories. The measurement of the biodistribution of radiopharmaceuticals is an important aspect in calculating absorbed dose from internally deposited radionuclides. Three phases are presented: data collection, data analysis and data processing. In the first phase, data collection, the identification of source regions, the determination of their appropriate temporal sampling and the acquisition of data are discussed. In the second phase, quantitative measurement techniques involving imaging by planar scintillation camera, SPECT and PET for the calculation of activity in source regions as a function of time are discussed. In addition, nonimaging measurement techniques, including external radiation monitoring, tissue-sample counting (blood and biopsy) and excreta counting are also considered. The third phase, data processing, involves curve-fitting techniques to integrate the source time-activity curves (determining the area under these curves). For some applications, compartmental modeling procedures may be used. Last, appendices are included that provide a table of symbols and definitions, a checklist for study protocol design, example formats for quantitative imaging protocols, temporal sampling error analysis techniques and selected calculational examples. The utilization of the presented approach should aid in the standardization of protocol design for collecting kinetic data and in the calculation of absorbed dose estimates.  (+info)

The effect of the antiscatter grid on full-field digital mammography phantom images. (3/3048)

Computer Analysis of Mammography Phantom Images (CAMPI) is a method for making quantitative measurements of image quality. This article reports on a recent application of this method to a prototype full-field digital mammography (FFDM) machine. Images of a modified ACR phantom were acquired on the General Electric Diagnostic Molybdenum Rhodium (GE-DMR) FFDM machine at a number of x-ray techniques, both with and without the scatter reduction grid. The techniques were chosen so that one had sets of grid and non-grid images with matched doses (200 mrads) and matched gray-scale values (1500). A third set was acquired at constant 26 kVp and varying mAs for both grid conditions. Analyses of the images yielded signal-to-noise-ratio (SNR), contrast and noise corresponding to each target object, and a non-uniformity measure. The results showed that under conditions of equal gray-scale value the grid images were markedly superior, albeit at higher doses than the non-grid images. Under constant dose conditions, the non-grid images were slightly superior in SNR (7%) but markedly less uniform (60%). Overall, the grid images had substantially greater contrast and superior image uniformity. These conclusions applied to the whole kVp range studied for the Mo-Mo target filter combination and 4 cm of breast equivalent material of average composition. These results suggest that use of the non-grid technique in digital mammography with the GE-DMR-FFDM unit, is presently not warranted. With improved uniformity correction procedure, this conclusion would change and one should be able to realize a 14% reduction in patient dose at the same SNR by using a non-grid technique.  (+info)

Computed radiography dual energy subtraction: performance evaluation when detecting low-contrast lung nodules in an anthropomorphic phantom. (4/3048)

A dedicated chest computed radiography (CR) system has an option of energy subtraction (ES) acquisition. Two imaging plates, rather than one, are separated by a copper filter to give a high-energy and low-energy image. This study compares the diagnostic accuracy of conventional computed radiography to that of ES obtained with two radiographic techniques. One soft tissue only image was obtained at the conventional CR technique (s = 254) and the second was obtained at twice the radiation exposure (s = 131) to reduce noise. An anthropomorphic phantom with superimposed low-contrast lung nodules was imaged 53 times for each radiographic technique. Fifteen images had no nodules; 38 images had a total of 90 nodules placed on the phantom. Three chest radiologists read the three sets of images in a receiver operating characteristic (ROC) study. Significant differences in Az were only found between (1) the higher exposure energy subtracted images and the conventional dose energy subtracted images (P = .095, 90% confidence), and (2) the conventional CR and the energy subtracted image obtained at the same technique (P = .024, 98% confidence). As a result of this study, energy subtracted images cannot be substituted for conventional CR images when detecting low-contrast nodules, even when twice the exposure is used to obtain them.  (+info)

3D angiography. Clinical interest. First applications in interventional neuroradiology. (5/3048)

3D angiography is a true technical revolution that allows improvement in the quality and safety of diagnostic and endovascular treatment procedures. 3D angiography images are obtained by reconstruction of a rotational angiography acquisition done on a C-arm (GE Medical Systems) spinning at 40 degrees per second. The carotid or vertebral selective injection of a total of 15 ml of non-ionic contrast media at 3 ml/sec over 5 seconds allows the selection of the "arterial phase". Four hundred sixty 3D angiographic studies were performed from December 1996 to September 1998 on 260 patients and have been analyzed in MIP (Maximum Intensity Projection) and SSD (Shaded Surface Display) views. The exploration of intracranial aneurysms is simplified and only requires, for each vascular axis, a biplane PA and Lateral run followed by a single rotational angiography run. The 3D angiography image is available on the workstation's screen (Advantage Workstation 3.1, GE Medical Systems) in less than 10 minutes after the acquisition of the rotational run. It therefore allows one to analyze, during the intervention, the aneurysm's angioarchitecture, in particular the neck, and select the best therapeutic technique. When endovascular treatment is the best indication, 3D angiography allows one to define the optimal angle of view and accurately select the microcoils dimensions. 3D angiography replaces the multiple oblique views that used to be required to analyze the complex aneurysms and therefore allows a reduction of the total contrast medium quantity, the patient X-ray dose and the length of the intervention time which is a safety factor. Also, in particular for complex cases, it brings additional elements complementing the results of standard 2D DSA and rotational angiograms. In the cervical vascular pathology, 3D angiography allows for a better assessment of the stenosis level and of dissection lesions. Our current research activities focus on the matching without stereotactic frame between 3D X-ray angiography and volumetric MR acquisition, which should allow us to improve the treatment of intracerebral arterio-venous malformations (AVMs).  (+info)

Biodistribution, radiation dosimetry and pharmacokinetics of 111In-antimyosin in idiopathic inflammatory myopathies. (6/3048)

In view of the established role of 111In-antimyosin in the detection of heart muscle pathology, radiation dose estimates were made for this substance. Biodistribution and biokinetic data were obtained from our studies, which failed to show abnormal uptake of 111In-antimyosin in localized sites of skeletal muscle involvement in patients with idiopathic inflammatory myopathies. METHODS: After intravenous administration of 74 MBq (2 mCi) 111In-antimyosin, gamma camera scintigraphy was performed in 12 adult patients with inflammatory muscle disease and in 2 control patients. Six whole-body scans were performed over 72 h, and uptake of 111In-antimyosin in organs was quantified using an attenuation-corrected conjugate counting method. Residence times in source organs were used with MIRDOSE software to obtain radiation dose estimates. Pharmacokinetic parameters were derived from serial whole-blood and plasma 111In concentrations. RESULTS: The tracer cleared slowly from the circulation, and highest organ uptakes were found in the marrow and liver; kidneys showed the highest concentrations. Uptake was also evident in spleen, the facial image and male genitalia. CONCLUSION: For a typical administered activity of 74 MBq 111In-antimyosin, the kidneys receive the highest dose (58 mSv), and the effective dose is 11 mSv. Radioactivity was cleared from plasma at an average rate of 136 mL/h, and the mean steady-state distribution was approximately 5 L plasma.  (+info)

MIRD Pamphlet No. 15: Radionuclide S values in a revised dosimetric model of the adult head and brain. Medical Internal Radiation Dose. (7/3048)

Current dosimetric models of the brain and head lack the anatomic detail needed to provide the physical data necessary for suborgan brain dosimetry. During the last decade, several new radiopharmaceuticals have been introduced for brain imaging. The marked differences of these tracers in tissue specificity within the brain and their increasing use for diagnostic studies support the need for a more anthropomorphic model of the human brain and head for use in estimating regional absorbed dose within the brain and its adjacent structures. METHODS: A new brain model has been developed that includes eight subregions: the caudate nuclei, the cerebellum, the cerebral cortex, the lateral ventricles, the lentiform nuclei, the thalami, the third ventricle and the white matter. This brain model is incorporated within a total revision of the head model presented in MIRD Pamphlet No. 5 Revised. Modifications include the addition of the eyes, the teeth, the mandible, an upper facial region, a neck region and the cerebrospinal fluid within both the cranial and spinal regions. RESULTS: Absorbed fractions of energy for photon and electron sources located in 14 source regions within the new model were calculated using the EGS4 Monte Carlo radiation transport code for particles in the energy range 10 keV-4 MeV. These absorbed fractions were then used along with radionuclide decay data to generate S values for 24 radionuclides that are used in clinical or investigational studies of the brain, 12 radionuclides that localize within the cranium and spinal skeleton and 12 radionuclides that selectively localize in the thyroid gland. CONCLUSION: A substantial revision to the dosimetric model of the adult head and brain originally published in MIRD Pamphlet No. 5 Revised is presented. This revision supports suborgan brain dosimetry for a variety of radiopharmaceuticals used in neuroimaging. Dose calculations for the neuroimaging agent 1231-tropane provide an example of the new model and yield mean brain doses that are consistent with published values. However, the absorbed dose to subregions within the brain such as the caudate and lentiform nuclei may exceed the average brain dose by a factor of up to 5.  (+info)

Dose-related effects of single focal irradiation in the medial temporal lobe structures in rats--magnetic resonance imaging and histological study. (8/3048)

The dose-related effects of single focal irradiation on the medial temporal lobe in rats were investigated by sequential magnetic resonance imaging and histological examination. Irradiation of 200 Gy as a maximum dose using 4 mm collimators with a gamma unit created an area of necrosis consistently at the target site within 2 weeks after irradiation. Irradiation of 100 Gy caused necrosis within 10 weeks, and 75 Gy caused necrosis within one year. Irradiation of less than 50 Gy did not induce necrosis consistently, although a restricted area of necrosis was created in the medial temporal structures including the intraparenchymal portion of the optic tract. 75 Gy may be the optimum dose for creating necrosis consistently in the medial temporal lobe structures. However, careful dose planning considering both dose-time and dose-volume relationships in necrosis development is necessary to avoid injury to vulnerable neural structures such as the optic tract when applying radiosurgical techniques to treat functional brain disorders in medial temporal lobe structures such as temporal lobe epilepsy.  (+info)

To compare routine dose liver CT reconstructed with filtered back projection (FBP) versus low dose images reconstructed with FBP and adaptive statistical iterative reconstruction (ASIR). In this retro
Comparison of the Breast Dose based on the Existence of the Bismuth Breast Protection Shield for Automatic Exposure Control and Manual Exposure Control with the Coronary Artery CT Angiography - coronary artery CT angiography;bismuth breast shield;MEC;AEC;breast dose;
Introduction: To accomplish a further decrease in radiation dose for coronary CT angiography (CCTA), advances in iterative reconstruction (IR) algorithms are necessary. The purpose of the present study was to investigate the impact of a latest generation adaptive statistical IR algorithm (ASiR-V, GE Healthcare) on CCTA signal intensity, noise and image quality (IQ).. Methods: Sixty-five consecutive patients underwent clinically indicated CCTA using a latest generation 256-slice CT scanner (Revolution CT, GE Healthcare) and an ultra-low-dose CCTA protocol (i.e. a BMI-adapted tube current of 180-310 mA and tube voltage of 80-120 kVp). Datasets from each patient were reconstructed at different levels of ASiR-V (i.e. ASiR-V 0% [= filtered back projection, FBP], 20%, 40%, 60%, 80% and 100%). The signal intensity and noise (i.e. attenuation and its standard deviation [in HU]) were measured in each reconstruction by placing a region of interest in the aortic root as well as the proximal RCA and LMA. ...
AIM: To quantify cumulative effective dose of intensive care unit (ICU) patients attributable to diagnostic imaging. METHODS: This was a prospective, interdisciplinary study conducted in the ICU of a large tertiary referral and level 1 trauma center. Demographic and clinical data including age, gender, date of ICU admission, primary reason for ICU admission, APACHE II score, length of stay, number of days intubated, date of death or discharge, and re-admission data was collected on all patients admitted over a 1-year period. The overall radiation exposure was quantified by the cumulative effective radiation dose (CED) in millisieverts (mSv) and calculated using reference effective doses published by the United Kingdom National Radiation Protection Board. Pediatric patients were selected for subgroup-analysis. RESULTS: A total of 2737 studies were performed in 421 patients. The total CED was 1704 mSv with a median CED of 1.5 mSv (IQR 0.04-6.6 mSv). Total CED in pediatric patients was 74.6 mSv ...
Diagnostic and therapeutic radiation fields are planned so as to reduce side-effects while maximising the dose to site but effects on healthy tissues are inevitable. Radiation causes strand breaks in DNA of exposed cells which can lead to chromosomal aberrations and cause malfunction and cell death. Several researchers have highlighted the damaging effects of high dose radiation but still there is a lacuna in identifying damage due to low dose radiation used for diagnostic purposes. Blood is an easy resource to study genotoxicity and to estimate the effects of radiation. The micronucleus assay and chromosomal aberration can indicate genetic damage and our present aim was to establish these with lymphocytes in an in vitro model to predict the immediate effects low dose radiation. Blood was collected from healthy individuals and divided into 6 groups with increasing radiation dose i.e., 0Gy, 0.10Gy, 0.25Gy, 0.50Gy, 1Gy and 2Gy. The samples were irradiated in duplicates using a LINAC in the radiation
Cardiac CT - radiation doses, dose management and practical issues. L 11. Answer True or False. Patient dose from a cardiac CT is equivalent to 20 chest conventional radiographies. In cardiac CT the radiation dose to the different organs is very similar to the catheterization procedures....
CT scans expose patients to radiation, but are often a necessary part of cancer treatment. City of Hopes new CT scanner offers high resolution images with lower radiation doses.
The Report Computed Tomography Systems Market to 2019 - Lower Radiation Dose and Improved Workflow in Advanced CT Systems to Increase Adoption Rates provides information on pricing, market analysis, shares, forecast, and company profiles for key industry participants. -
Authors: Zhao, Yongxia , Li, Dongxue , Liu, Zhichao , Geng, Xue , Zhang, Tianle , Xu, Yize Article Type: Research Article Abstract: OBJECTIVE: To determine the optimal pre-adaptive and post-adaptive level statistical iterative reconstruction V (ASiR-V) for improving image quality and reducing radiation dose in coronary computed tomography angiography (CCTA). METHODS: The study was divided into two parts. In part I, 150 patients for CCTA were prospectively enrolled and randomly divided into 5 groups (A, B, C, D, and E) with progressive scanning from 40% to 80% pre-ASiR-V with 10% intervals and reconstructing with 70% post-ASiR-V. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Subjective image quality was assessed using a 5-point scale. The CT dose index volume …(CTDIvol ) and dose-length product (DLP) of each patient were recorded and the effective radiation dose (ED) was calculated after statistical analysis by optimizing for the best pre-ASiR-V value with ...
OBJECTIVE: To compare radiation doses delivered at prospectively ECG-triggered sequential- (SEQ), retrospectively ECG-gated spiral- (RETRO) and prospectively ECG-triggered high-pitch spiral- (HP) computed tomography coronary angiography (CTCA) protocols, as well as catheter coronary angiography (CCA) using an anthropomorphic phantom. MATERIALS AND METHODS: An anthropomorphic Alderson phantom equipped with 50 thermoluminescent dosimeters (TLDs) was scanned using different CTCA protocols and an uncomplicated diagnostic CCA examination was simulated. Absorbed doses were experimentally determined and effective doses calculated using the dose-length product (DLP) for CTCA and the dose-area product (DAP) for CCA, as well as according to International Commission on Radiation Protection (ICRP) publications 60 and 103. RESULTS: Effective organ doses were significantly lower for HP protocols (100kV: 0.17±0.26mSv; 120kV: 0.26±0.39mSv) compared to SEQ protocols (100kV: 0.50±0.79mSv; 120kV: 0.90±1.41mSv; ...
British Committee on Radiation Units and Measurements, (1997) Advice on the implications of the conversion coefficients for external radiations published in ICRP publication 74 and by ICRU publication 57. J. Radiol. Prot., 17. pp. 201-204. Full text not available from this repository ...
Objectives To report on a dose survey conducted by the French societies of radiology and paediatric imaging (SFR and SFIPP) and the French public service expert in nuclear and radiological risks...
Objectives: This study aimed to measure the absorbed doses in selected organs for prospectively ECG-triggered coronary computed tomography angiography (CCTA) using five different generations CT scanners in a female adult anthropomorphic phantom and to estimate the effective dose (HE). Materials and Methods: Prospectively ECG-triggered CCTA was performed using five commercially available CT scanners: 64-detector-row single source CT (SSCT), 2 × 32-detector-row-dual source CT (DSCT), 2 × 64-detector-row DSCT and 320-detector-row SSCT scanners. Absorbed doses were measured in 34 organs using pre-calibrated optically stimulated luminescence dosimeters (OSLDs) placed inside a standard female adult anthropomorphic phantom. HE was calculated from the measured organ doses and compared to the HE derived from the air kerma-length product (PKL) using the conversion coefficient of 0.014 mSv_mGy-1_cm-1 for the chest region. Results: Both breasts and lungs received the highest radiation dose during CCTA ...
Radiation dose from a CT examination in standard body regions can be estimated from the dose-lenght product (DLP) that each CT outputs. This table shows known commonly used coefficients and their adjustment in two particular CT machines.
OBJECTIVE The clinical utility of a latest generation iterative reconstruction algorithm (adaptive statistical iterative reconstruction [ASiR-V]) has yet to be elucidated for coronary computed tomography angiography (CCTA). This study evaluates the impact of ASiR-V on signal, noise and image quality in CCTA. METHODS Sixty-five patients underwent clinically indicated CCTA on a 256-slice CT scanner using an ultralow-dose protocol. Data sets from each patient were reconstructed at 6 different levels of ASiR-V. Signal intensity was measured by placing a region of interest in the aortic root, LMA, and RCA. Similarly, noise was measured in the aortic root. Image quality was visually assessed by 2 readers. RESULTS Median radiation dose was 0.49 mSv. Image noise decreased with increasing levels of ASiR-V resulting in a significant increase in signal-to-noise ratio in the RCA and LMA (P , 0.001). Correspondingly, image quality significantly increased with higher levels of ASiR-V (P , 0.001). CONCLUSIONS ...
Background Optimization of CT radiation dose is important for children due to their higher risk of radiation-induced adverse effects. Anatomical structures with high inherent contrast, such as bones can be imaged at very low radiation doses by optimizing scan parameters. Purpose To assess feasibility of sub-milliSievert whole spine CT scanning protocol for evaluation of scoliosis in children. Material and Methods With approval of the ethical board, we performed whole spine CT for evaluation of scoliosis in 22 children (age range, 3-18 years; mean age, 13 years; 13 girls, 9 boys) on a 128-slice dual source multidetector-row CT scanner. Lowest possible quality reference mAs value (image quality factor for xy-z automatic exposure control or xyz-AEC, CARE Dose 4D) was selected on a per patient basis. Remaining parameters were held constant at 3.0:1 pitch, 128 × 0.6 mm detector collimation, 115.2 mm table feed per gantry rotation, 100 kVp, and 1 and 3 mm reconstructed sections. Average mAs, ...
BACKGROUND AND PURPOSE: Advancements in medical device and imaging technology as well as accruing clinical evidence have accelerated the growth of the endovascular treatment of cerebrovascular diseases. However, the augmented role of these procedures raises concerns about the radiation dose to patients and operators. We evaluated patient doses from an x-ray imaging platform with radiation dose-reduction technology, which combined image noise reduction, motion correction, and contrast-dependent temporal averaging with optimized x-ray exposure settings. MATERIALS AND METHODS: In this single-center, retrospective study, cumulative dose-area product inclusive of fluoroscopy, angiography, and 3D acquisitions for all neurovascular procedures performed during a 2-year period on the dose-reduction platform were compared with a reference platform. Key study features were the following: The neurointerventional radiologist could select the targeted dose reduction for each patient with the dose-reduction platform,
The magnitude of the risks from low doses of radiation is one of the central questions in radiological protection. It is particularly relevant when discussing the justification and optimization of diagnostic medical exposures. Medical X-rays can undoubtedly confer substantial benefits in the healthcare of patients, but not without exposing them to effective doses ranging from a few microsieverts to a few tens of millisieverts. Do we have any evidence that these levels of exposure result in significant health risks to patients? The current consensus held by national and international radiological protection organizations is that, for these comparatively low doses, the most appropriate risk model is one in which the risk of radiation-induced cancer and hereditary disease is assumed to increase linearly with increasing radiation dose, with no threshold (the so-called linear no threshold (LNT) model). However, the LNT hypothesis has been challenged both by those who believe that low doses of radiation are
The magnitude of the risks from low doses of radiation is one of the central questions in radiological protection. It is particularly relevant when discussing the justification and optimization of diagnostic medical exposures. Medical X-rays can undoubtedly confer substantial benefits in the healthcare of patients, but not without exposing them to effective doses ranging from a few microsieverts to a few tens of millisieverts. Do we have any evidence that these levels of exposure result in significant health risks to patients? The current consensus held by national and international radiological protection organizations is that, for these comparatively low doses, the most appropriate risk model is one in which the risk of radiation-induced cancer and hereditary disease is assumed to increase linearly with increasing radiation dose, with no threshold (the so-called linear no threshold (LNT) model). However, the LNT hypothesis has been challenged both by those who believe that low doses of radiation are
TY - BOOK AU - Mitrović, Marko PY - 2018 UR - UR - UR - AB - Usage of computed tomography (CT) is very frequent, both in human and veterinary medicine. Bearing in mind that the radiation dose, that patient receive during CT examination, is several times higher than during conventional radiography, much attention is devoted to evaluate necessity of this diagnostic procedure and its optimization, along with the minimal exposure of patients to the radiation load. According to this, the main goal of these investigations was to explore a correlation between absorbed radiation doses and the degree of activity of antioxidant enzymes in rabbit organs following CT examination performed by different tube voltage and amperage values. Experiment was conducted on 66 mature male New Zealand rabbits divided in 11 groups, consisting of six animals ...
Background Endovascular aneurysm repair (EVAR) requires lifelong surveillance by computed tomography angiography (CTA). This is attended by a substantial accumulation of radiation exposure. Iterative reconstruction (IR) has been introduced to approach dose reduction. Purpose To evaluate adaptive statistical iterative reconstruction (ASIR) at different levels of tube voltage concerning image quality and dose reduction potential in follow-up post EVAR. Material and Methods One hundred CTAs in 67 patients with EVAR were examined using five protocols: protocol A (n = 40) as biphasic standard using filtered back projection (FBP) at 120 kV; protocols B (n = 40), C (n = 10), and D1 (n = 5) biphasic using ASIR at 120, 100, and 80 kV, respectively; and protocol D2 (n = 5) with a monophasic splitbolus ASIR protocol at 80 kV ...
View this term paper on Radiology Reducing Patient Exposure and. The quality of image can be affected through lack of correct levels of data compression and...
The issue of radiation dosage is confusing to many clinicians. Part of this confusion is related to the terminology, especially given that radiation-related quantities and effects can be expressed in many different ways and competing terms have been used inconsistently in the past. Radiation dose or absorbed radiation dose refers to the amount of energy deposited by ionizing radiation per unit mass in a patients body as a result of exposure. The units of absorbed dose are rads or millirads in conventional units or gray in SI units. A pertinent concept is that of the effective dose, expressed in units of rem or millirem or the SI unit of sievert or millisievert. Effective dose takes into account the different risks of absorbed dose to various organs and is a useful method of comparing risk among different diagnostic tests. The effective dose equivalent is the sum of the products of the effective dose to the organ or tissue and weighting factors specific to each of the body organs or tissues. The ...
by admin , Mar 15, 2013. Radiation dose received by patients during invasive cardiology procedures has the potential to cause skin damage and is assumed to include a small cancer risk. To help ensure patient safety, it is desirable to minimize patient radiation dose to patients undergoing these procedures. An inherent benefit of reduced patient dose is reduced dose to physician operators and staff. Previous studies have tested patient radiation dose-reduction initiatives for radiofrequency ablation and invasive coronary artery procedures. Few studies, however, have explored the effects of using sustained patient radiation dose-reduction initiatives in larger, diverse invasive cardiovascular settings. A Progressive Movement on Patient Radiation In an issue of JACC: Cardiovascular Interventions, Kenneth A. Fetterly, PhD, and colleagues had a single-center study published that investigated the effects of sustained practice and x-ray system technical changes on radiation doses administered to adult ...
NIH Funding Opportunities and Notices in the NIH Guide for Grants and Contracts: Decreasing Patient Radiation Dose from CT Imaging: Achieving Sub-mSv Studies (U01) PAR-12-206. NIBIB
Every second resident of Europe will, on average, undergo a medical x-ray examination each year. Diagnostic radiology is responsible for the largest proportion of artificial radiation exposure for the European population. The introduction of digital radiography promises to reduce this burden, but to what extent remains unclear.
Introduction: Coronary computed tomography angiography (CTA) is increasingly used for the non-invasive evaluation of symptomatic coronary artery disease (CAD). However, potential risks of coronary CTA include exposure to ionizing radiation. Lowering tube voltage can significantly decrease radiation dose, but the effects on image quality are unknown.. Hypothesis: To determine if a very low tube voltage of 80kVp is feasible to further minimize radiation dose and maintain diagnostic image quality of coronary CTA.. Methods: We analyzed 191 consecutive patients with low-intermediate probability of CAD, who were evaluated for acute chest pain with 64-multidetector row coronary CTA (Lightspeed, GE Medical). Tube voltage protocols used either standard 120kVp, low 100kVp, or very low 80kVp, depending on physician discretion. Primary end points were radiation effective dose (mSv) and image quality assessed with a 4-point grading system (0 = excellent, 3 = nondiagnostic). Secondary analysis included the ...
Our direct, intraindividual head-to-head comparison in the same patient population shows that compared with a routine radiation dose FBP protocol, a 50% reduced radiation dose image acquisition using IR preserves image quality and, more importantly, diagnostic accuracy at coronary CTA. These findings illustrate the potential of substantial radiation dose reduction across the population for coronary CTA studies, enabled by a reduced tube current-time product when iteratively reconstructed, without jeopardizing the diagnostic yield of the examination.. Since its inception, radiation doses associated with noninvasive coronary CTA had risen with each new generation of multidetector-row CT systems and had reached its zenith with the launch of the first-generation 64-slice scanners in the year 2004. With these platforms, radiation doses from coronary CTA were reported to be as high as approximately 30 mSv, with an estimated median of approximately 12 mSv (15). Since then, vigorous efforts have been ...
Sponsored by Philips. Background Increased utilization of CT in clinical imaging,1 together with the potential for increased cancer risk associated with pati...
Since the 1970s, mammograms have made a huge impact on detecting breast cancer in its earliest stages, when it is most treatable - it remains the best method for early detection today, says Mary Lechner, MD, medical director at Park Nicollet Jane Brattain Breast Center.. During a mammogram, low dose radiation (X-ray) is passed through a compressed breast, source The compression is necessary to provide an accurate picture. Images produced by mammograms can detect a tumor as early as two years before a doctor or patient can feel a lump.. I tell women that yearly mammograms can reassure them that their breasts are normal - and if there is an abnormality, mammograms can detect it early, when there are more treatment options if it proves to be cancer, and survival rates are higher, Dr. Lechner says.. ...
All studies involving use of ionizing radiation should be performed in accordance with the ALARA (As Low As Reasonably Achievable) principle, especially in children. In this study, the prospective ECG triggering technique with low voltage was used in dual-source computed tomography (DSCT) angiography to investigate if image quality with low radiation dose could be satisfactory in pediatric patients with congenital heart disease. Sixty pediatric patients with suspected congenital cardiovascular anomalies were enrolled prospectively in the study. They were randomly assigned to two groups for DSCT angiography. Group A were scanned by prospective ECG-triggering computed tomography angiography (CTA) with 80 kV tube voltage, while group B by used non-ECG-gated CTA with the same tube voltage. The anomaly accuracy was evaluated based on the surgical and/or conventional cardiac angiography findings. The overall image quality was assessed on a five-point scale. And the diagnostic accuracy and radiation dose was
On-line megavoltage computed tomography (MVCT) images are used to verify patient daily set-up in Hi-ART helical TomoTherapy unit. To evaluate the patient dose from MVCT scanning in image guidance, weighted computed tomography (CT) dose index (CTDIw) was measured with PTW TM30009 CT pencil chamber in head and body phantoms for slice thicknesses of 2, 4 and 6 mm with different scan lengths. Dose length products (DLPs) were subsequently calculated. The CTDIw and DLP were compared with XVI kV CBCT and Brilliance simulator CT for routine clinical protocols. It was shown that CTDI and DLP had close relationship with the slice thickness and the scan length. The dose distribution in the transversal plane was very inhomogeneous due to the attenuation of the couch. Patient dose from MVCT was lower than XVI CBCT for the head scan, while larger for body scan. CTDIw, which is measured easily and reproducibly, can be used to assess the patient dose in MVCT. Regular measurement should be performed in QA & QC ...
One of the technical disadvantages of CT is the use of ionizing radiation. Although the normal radiation dosage for a routine brain CT study is between 2 and 5 mSv, it is important to note that radiation dose is additive, additional acquisition series during a single exam sitting will increase dose. Care must be taken to reduce exposure when imaging pediatric patients, and ALARA (As low as reasonably achievable) principle should be implemented in all situations to patients and personnel. With the advent of MDCT, CTP and CTA, the benefit must be weighed against the increased radiation doses associated with these techniques.. Advanced noise reduction and image reconstruction technologies result improvement in qualitative and quantitative aspects of CT image quality, with significant reductions in radiation exposure (30-40% lower radiation doses).. Additional complications from CT scan are those associated with the use of intravenous contrast agents mentioned before, which are essential for CTP, ... is the largest and most comprehensive community Web site for medical imaging professionals worldwide. Radiologists, technologists, administrators, and industry professionals can find information and conduct e-commerce in MRI, mammography, ultrasound, x-ray, CT, nuclear medicine, PACS, and other imaging disciplines.
Authors: Tan, Wenli , Zhan, Songhua , Yang, Shuohui , Zhuang, Yuan , Cheng, Ruixin , Zhan, Hongsheng Article Type: Research Article Abstract: OBJECTIVE: The aim of this study was to investigate the significance of the combined use of BMI and AEC in reducing the radiation dose of CT volume scans of the lumbar spine. METHODS: A prospective study was performed to continuously collect data from 50 patients (age range from 19 to 60 years, male versus female 20/30) whose BMIs were less than 25 kg/m^{2} (group A) and 50 patients (age range from 21 to 82 years, male …versus female 24/26) whose BMIs were equal to or more than 25 kg/m^{2} (group B). The 50 patients in each group were randomly divided into 5 subgroups with each subgroup having lower radiation dose from subgroup 1 to 5. All the patients were performed lumbar spiral CT scans (GE LightSpeed VCT 64-slice scanner) and the scan parameters were different in different subgroups. Volume CT dose index (CTDIvol) was recorded. The qualities of the ...
Scans were performed by the use of a 64-channel MDCT scanner (Brilliance 64, Philips Healthcare, Cleveland, Ohio) without the administration of medication to lower the patients heart rate. Scan parameters were a collimation of 64 × 0.625 mm, rotation time 0.42 s, tube voltage 120 kV, and tube current of 500 to 600 mAs corresponding to an approximate mean radiation dose of 5.5 mSv. A dose modulation protocol was applied to reduce the radiation dose during systole (17). An ECG was recorded simultaneous to the CT scan to enable retrospective gating of the image data. A dedicated cardiac gating algorithm was used that identified the same physiological phases of the cardiac cycle while taking into account the nonlinear changes in the individual cardiac states with the heart rate variations during the CT acquisition (18). A cardiac adaptive multisegment reconstruction technique was used that combined data from consecutive cardiac cycles, thus significantly improving temporal resolution between 53 ...
The RSNA 2011 conference marks the 97th Scientific Assembly and Annual Meeting. This event, the worlds premier medical meeting for radiologic professionals, is being held on November 27 through December 2 at the McCormick Place in Chicago. The annual conference includes unparalleled education and professional development, networking opportunities, and a cutting- edge technical exhibition.. I will be involved in a number of events, both as a presenter and an author. The presentations that I will be involved in include:. • Presenter- Hot Topics: Dual- Energy CT on Tuesday, November 29 from 7:15 am to 8:15 am.. • Presenter- Refresher: Mind Your Own Business! Required Business Skills for Your First Job on Thursday, December 1 from 4:30 pm- 6:00 pm.. • Author/ Participant- Gastrointestinal Series: Scientific Formal Presentation (Dual-Energy CT of Hypervascular Liver Lesions: Evaluation of Lesion Contrast-to-Noise with Different Monochromatic keV Reconstructed Images) on Monday, November 28 ...
June 30, 2017 -- Egypt has unveiled the first national diagnostic reference levels (DRLs) for CT, but senior radiologists still have concerns about radiation dose. Areas for improvement include the selection of exposure parameters for different examinations, taking into account the image quality, with particular attention on facilities using consistently higher doses compared with DRLs. Discuss ...
Lung cancer is the leading cause of cancer-related death worldwide. The poor prognosis of lung cancer has barely changed in the last decades, but the prognosis is better when the disease is detected earlier.
Poster: EuroSafe Imaging 2020 / ESI-07643 / Comparative study of patient doses and establishment of local diagnostic reference levels in Computed Tomography in line with the new ICRP recommendations by: S. Avramova-Cholakova, E. Kulama
The situation in Italy regarding radiation dose to patients undergoing Multidetector row Computed Tomography (MDCT) scans is unclear despite Italian law
All micro life cultures will be delivered to you within two business days when order is placed before 12:00 pm EST. Your specimens or cultures will arrive in good condition or we will send a free replacement. Requesting a delivery date of Wednesday, Thursday, or Friday ensures healthy delivery of your live specimens. Live materials will not be delivered on Mondays. For Tuesday deliveries, additional shipping charges may apply. Contact Boreal Science customer service (800-387-9393) to arrange a Tuesday live materials delivery. For live materials coupon redemption, visit In instances of severe weather, we may delay or cancel a shipment if it will not arrive safely. See our home page for the latest updates if you suspect weather could be an issue in your area. If your school is closed due to weather, please call customer service to let us know and we will hold your specimen and reschedule at your convenience. ...
1. Thyroid-accelerated metamorphosis in the larval frog is accompanied by changes in the hemopoietic centers and in the blood cell distribution in the various regions of the body. These changes are interpreted as results of the fundamental change in basal metabolic rate induced by the thyroid treatment.. 2. There is initiation of the shift of hemopoietic locus from the kidney, the larval hemopoietic organ, to the spleen, the adult hemopoietic organ. The spleen, being chiefly an erythrocyte producer, becomes of greater importance with the transition from the lower metabolic rate to the higher, since greater erythropoiesis becomes necessary to supply the physical basis for the maintenance of the higher metabolic rate.. 3. It is suggested that the appearance of red bone marrow in the later history of the frog is correlated with a still higher metabolic rate. Phylogenetically, in the vertebrate series, red bone marrow is also associated with higher metabolic rate.. 4. The new metabolic rate ...
This document contains useful information for those taking this medication. It is not intended, in any way, to replace the advice of a trained health professional. For more information, consult the manufacturers literature, where you will find additional information about uncommon side effects as well as contraindications associated with this product.. ...
Agenda Item 5a ISRRT Position Statement: The implementation and use of Diagnostic Reference Levels (DRLs) in Medical Imaging by Radiographers/Radiological Technologists Read More
Research, published in PLOS Genetics, reports that low doses of radiation used in medical imaging may lead to mutations in cell cultures.. Prof Geraldine Thomas, Professor of Molecular Pathology, Imperial College London, said:. This is an interesting paper that seeks to investigate the how various types of DNA repair affect random integration of DNA from non-chromosomal sources following a double strand break. This paper should not be taken as evidence that low dose radiation exposure is likely to result in DNA integration when used in diagnostic procedures in vivo, nor should this work be taken for evidence that exposure to low dose radiation results in cancer in man. In terms of the mechanisms by which this might occur it is interesting, but caution should be taken before extrapolating results on cell lines (murine or human) into the likely effects of radiation in vivo in man. Cell lines are produced as a result of clonal selection in vitro - this process results in a change in the genetic ...
Images of excised breast samples of 2-4 cm thickness were acquired at beamline ID17 (The Biomedical Beamline), with a mean glandular dose of only 0.12 mGy. In Figure 117, the raw EI image (Figure 117a) and the retrieved phase image (Figure 117b) are compared to the conventional mammogram acquired at a hospital (Figure 117c) (32 kVp, dose of 4.1 mGy). Despite the high X-ray energy and the extremely low radiation dose, all the breast structures are highlighted in the raw EI image by the refraction-induced signal present at their boundaries. The area contrast typical of conventional X-ray images (more easily interpretable to radiologists), in turn, is restored in the retrieved phase map. This image depicts breast features with at least the same quality as in the conventional mammogram, although at a dose reduced by more than one order of magnitude.. The EI method has also been demonstrated to work efficiently in table-top setups exploiting conventional rotating anode sources [3]. The next step in ...
Monte Carlo estimation of the absorbed dose for CMS with a forward ECAL sampling calorimeter (EE) under HL-LHC conditions using FLUKA. The plot shows the dose absorbed in the EE for an integrated luminosity of 3000.0 fb-1 as a function of the radiation length X_0. The absorbed dose rate is averaged over 48 cm ,R ,109 cm, corresponding to 1.8 , η , 2.6 at z = 320 cm. The z-coordinate is converted to radiation length by scaling with the effective radiation length for each calorimeter. The conversion factors are: 0.88 cm/X0 for PbWO4, 0.88 cm/X0 for YSO/W, 0.508 cm/X0 for LYSO/W and 0.616 cm/X0 for CeF3/W. The bin size is 10% of the effective radiation length of the respective calorimeter to visualise differences between the active and passive layers. The grid starts at the end of the first scintillator layer, each line indicates the end of anscintillator layer/start of an absorber layer. The calculated dose corresponds to the dose absorbed in the implemented material. Any material not ...
TY - JOUR. T1 - Cumulative radiation dose in patients with aneurysmal subarachnoid hemorrhage. AU - Mamourian, A.. AU - OShea, M.. AU - Maidment, A. D.A.. PY - 2010/11/1. Y1 - 2010/11/1. UR - UR - U2 - 10.3174/ajnr.A2260. DO - 10.3174/ajnr.A2260. M3 - Letter. C2 - 20966050. AN - SCOPUS:78649648606. VL - 31. SP - E87-E88. JO - American Journal of Neuroradiology. JF - American Journal of Neuroradiology. SN - 0195-6108. IS - 10. ER - ...
TY - JOUR. T1 - Evaluation of absorbed radiation dose to working staff during cardiac catheterization procedures. AU - Chong, N. S.. AU - Yin, W. H.. AU - Chan, P.. AU - Cheng, M. C.. AU - Ko, H. L.. AU - Jeng, S. C.. AU - Lee, J. J S. PY - 2000. Y1 - 2000. N2 - Background. Cardiac catheterization has been used frequently for the evaluation and treatment of patients with heart diseases. The working staff, particularly cardiologists who perform these procedures, have the highest potential risk of receiving high radiation doses due to close contact with patients. The purpose of this study was to measure and evaluate the accumulated radiation dosage of the cardiologists while they were performing clinical procedures in the cardiac catheterization laboratory. The working environment of the catheterization laboratory was also monitored for radiation. Methods. Thermoluminescent dosimeters (TLDs) with very high sensitivity were employed for dose evaluations. They were taped to various parts of the body ...
TY - JOUR. T1 - Importance of pre-treatment radiation absorbed dose estimation for radioimmunotherapy of non-Hodgkins lymphoma. AU - Eary, Janet F.. AU - Krohn, Kenneth A.. AU - Press, Oliver W.. AU - Durack, Lawrence. AU - Bernstein, Irwin D.. PY - 1997/10/1. Y1 - 1997/10/1. N2 - Non-Hodgkins lymphoma 1-131 radioimmunotherapy data were analyzed to determine whether a predictive relationship exists between radiation absorbed doses calculated from biodistribution studies and doses derived from patient size. Radioactivity treatment administrations scaled to patient size (MBq/kg or MBq/m2) or fixed MBq doses do not produce consistent radiation absorbed dose to critical organs. Treatment trials that do not provide dose estimates for critical normal organs are less likely to succeed in identifying a clinical role for radioimmunotherapy.. AB - Non-Hodgkins lymphoma 1-131 radioimmunotherapy data were analyzed to determine whether a predictive relationship exists between radiation absorbed doses ...
TY - JOUR. T1 - Evaluation of low-dose CT angiography with model-based iterative reconstruction after endovascular aneurysm repair of a thoracic or abdominal aortic aneurysm. AU - Hansen, Neil J.. AU - Kaza, Ravi K.. AU - Maturen, Katherine E.. AU - Liu, Peter S.. AU - Platt, Joel F.. PY - 2014/3. Y1 - 2014/3. N2 - OBJECTIVE. The objective of our study was to evaluate image quality and overall adequacy of low-dose CT angiography (CTA) with model-based iterative reconstruction (MBIR) in patients who had undergone endovascular aneurysm repair (EVAR) of a thoracic or abdominal MATERIALS AND METHODS. Thirty patients, all of whom had undergone standard-dose CTA performed previously with adaptive statistical iterative reconstruction (ASIR), underwent low-dose CTA for surveillance after EVAR. Two radiologists randomly evaluated both studies, and quality parameters were assessed. The maximal aneurysm diameter was measured, and the images were evaluated to see whether an endoleak was present. The image ...
The National Radiological Protection Board (NRBP) has recently revised the radiation dose for typical x ray examinations. For example, an abdominal/pelvic CT scan would typically lead to an effective dose of 10 mSv, which is an equivalent of 4.5 years of natural background radiation.8 This radiation exposure was estimated to carry a 1:2000 risk of fatal cancer in the 16-69 year old patient population (personal communication from NRPB). For older patients, this may be halved but for younger patients increased up to fivefold. Put another way, this is equal to 250-300 fatal cancers for every 1 million abdominal/pelvic CT scans.. These values are calculated using a probability coefficient, which was developed by the International Commission on Radiological Protection (ICRP), based on historical epidemiological cohorts and other research.9 It is worth noting that the cancer risk attributed to radiation exposure has constantly risen over time as longer term follow up information from the Hiroshima and ...
TCT-147 Patient radiation exposure with a novel X-ray imaging technology during coronary angiography and angioplasty Conference Paper ...
Cancer is a stochastic effect of radiation, meaning that the probability of occurrence increases with effective radiation dose, but the severity of the cancer is independent of dose. The speed at which cancer advances, the prognosis, the degree of pain, and every other feature of the disease are not functions of the radiation dose to which the person is exposed. This contrasts with the deterministic effects of acute radiation syndrome which increase in severity with dose above a threshold. Cancer starts with a single cell whose operation is disrupted. Normal cell operation is controlled by the chemical structure of DNA molecules, also called chromosomes. When radiation deposits enough energy in organic tissue to cause ionization, this tends to break molecular bonds, and thus alter the molecular structure of the irradiated molecules. Less energetic radiation, such as visible light, only causes excitation, not ionization, which is usually dissipated as heat with relatively little chemical damage. ...
TOKYO (Kyodo) - High radiation doses were reported Thursday in spots in Tokyo and neighboring Chiba Prefecture, both over 200 kilometers away from the crippled Fukushima Daiichi nuclear plant, with their readings found to exceed current dose levels in some evacuation zones around the plant.. Airborne radiation of up to 3.35 microsieverts per hour was recorded Thursday along a sidewalk in a residential area in Tokyos Setagaya Ward in an inspection commissioned by the ward, and a citizens group detected up to 5.82 microsieverts close to the ground at a childrens theme park in Funabashi, Chiba Prefecture, local officials said.. While officials are still investigating whether the radiation resulted from the nuclear accident, the levels detected were both higher than the 2.17 microsieverts per hour measured Wednesday at the village office in Iitate, Fukushima Prefecture. The village is 45 kilometers from the plant and designated as an evacuation zone due to the relatively high ...
Mammoth Hospital upgraded to a new medical imaging technology, which offers the latest advances in low radiation dose imaging.. In the past, radiology technologists had to use standard radiation doses to get high diagnostic image quality. Now, technologists can use cutting edge computer technology to create quality images from low radiation dose scans.. Radiation dosage during CT scanning has been a major concern and this will put Mammoth among hospitals in the country that have addressed this concern, said Gary Boyd, CEO of Mammoth Hospital.. ...
Red Bones, Paper Mario: The Thousand-Year Door. Red Bones are stronger than Dull Bones but not as strong as Dry Bones. They act the same as others in the Bones family, except Red Bones seem to summon Dull Bones more often. They are the only ones with blue eyes, and they seem to be able to command Dull Bones. They only appear in Paper Mario: The Thousand-Year Door, where they are present only in Hooktail Castle and a certain puzzle in the Palace of Shadows Riddle Tower, although the tattle of a Red Bones can be found in Franklys trash can after Chapter 1. ...
Head and neck cancers are common in several regions of the world and the treatment usually includes radiotherapy. This treatment can generate adverse effects to the salivary flow, with a relationship between the dose and the damage caused. Salivary gland cells are highly permeable to water and therefore, they express aquaporins (AQPs). This study analyzed changes in the expression and location of these proteins and identified morphological changes induced by low radiation in rat submandibular gland. Female rats were divided into control and irradiated groups. Immunohistochemistry analysis allowed confirming the presence of AQP1 in the blood vessel endothelium. Intense and steady labelling granules were also observed in the cytoplasm of submandibular gland ductal cells. In addition, there was AQP5 positive labelling in ductal cells delimiting the lumen of intercalated duct, in the cytoplasm and membrane of acinar cells. Finally, the decrease of AQP labelling in irradiated animal glands validated ...
CT technology continues to rapidly evolve, especially in the area of reducing radiation dose while preserving IQ. In the present study, we used a high-pitch, ECG-triggered scan mode on a second-generation DSCT scanner to assess PV and LA anatomy in patients with SR or AF. Our results show that PV imaging can be performed with a low median radiation dose of 1.4 mSv and achieves good to excellent CT IQ. CT scanning is feasible, with no difference in IQ between patients in AF compared with SR, without the need for heart rate-lowering agents. When compared with prior standard CT protocols, we observed a remarkable reduction in radiation dose for both patients with SR and AF with this high-pitch CT protocol. Scan time acquisition was much faster with this low radiation CT scanning technique compared with MRI, with excellent agreement of PV anatomy between the 2 imaging modalities.. Thorough assessment of PV and LA anatomy with a noninvasive imaging modality, such as CT, is important in patients with ...
How are patients prepared for nuclear medicine procedures? Nuclear medicine is a specialized branch of modern medicine that exploits the process of radioactivity for imaging, diagnosis, and treatment. Many imaging techniques inject small amounts of radioactive material into the body, which are then tracked by a sensing device specific to the type of radiation emitted […]
TY - JOUR. T1 - Size effect on dose output in phantoms of x-ray tubes in medical x-ray imaging. AU - Zheng, Xiaoming. AU - Nardi, Laura. AU - Murray, Mark. N1 - Includes bibliographical references.. PY - 2017/11/27. Y1 - 2017/11/27. N2 - The purpose of this work was to study how patient size affects the exponent of the power law relating dose to x-ray tube potential in clinical x-ray imaging using phantoms. Computed tomography (CT) dose phantoms of 16 cm and 32 cm in diameter were used to model children and adults respectively. A Fujifilm digital radiographic imaging system and a GE Discovery HD 750 CT scanner were employed to image both phantoms. For the Fujifilm radiographic imaging system, doses were measured at various locations of entrance, centre, exit as well as side locations of the phantoms using a PTW DIADOS diagnostic dosimeter. Standard procedure was employed for CT dose measurements for the GE CT scanner. X-ray exposures were varied by employing various tube voltages kVp and tube ...
Methods: We assembled a cohort of 308 297 radiation-monitored workers employed for at least 1 year by the Atomic Energy Commission, AREVA Nuclear Cycle, or the National Electricity Company in France, the Departments of Energy and Defence in the USA, and nuclear industry employers included in the National Registry for Radiation Workers in the UK. The cohort was followed up for a total of 8·22 million personyears. We ascertained deaths caused by leukaemia, lymphoma, and multiple myeloma. We used Poisson regression to quantify associations between estimated red bone marrow absorbed dose and leukaemia and lymphoma mortality ...
Following radiation-release incidents, rigorous evaluation of radiation exposure is fundamental for better understanding of the future health risks as well as for effective radiation protection planning. After the Fukushima incident, because of limited scientific evidence and knowledge with regard to dose reconstruction, we have faced inaccuracy in the government dose estimation model.9 ,12 Hence, to ensure as much accuracy as possible, direct dose measurements using individual radiation dosimeters have been adopted by many local authorities as a major component of their radiation protection policies.14 However, evaluations of proper dosimeter use by individuals is greatly lacking; the errors arising from improper use of the dosimeters are also unknown because of lack of information on users daily behaviour and the conditions under which the dosimeters are worn. Here, the external radiation screening programme provided by Minamisoma City offered a unique and valuable opportunity to address ...
[18F]UCB-H was developed as a novel radiotracer with a high affinity for synaptic vesicle protein 2A, the binding site for the antiepileptic levetiracetam. The objectives of this study were to evaluate the radiation dosimetry of [18F]UCB-H in a preclinical trial and to determine the maximum injectable dose according to guidelines for human biomedical research. The radiation dosimetry was derived by organ harvesting and dynamic micro positron emission tomography (PET) imaging in mice, and the results of both methods were compared. Twenty-four male C57BL-6 mice were injected with 6.96 ± 0.81 MBq of [18F]UCB-H, and the biodistribution was determined by organ harvesting at 2, 5, 10, 30, 60, and 120 min (n = 4 for each time point). Dynamic microPET imaging was performed on five male C57BL-6 mice after the injection of 9.19 ± 3.40 MBq of [18F]UCB-H. A theoretical dynamic bladder model was applied to simulate urinary excretion. Human radiation dose estimates were derived from animal data using the
TY - JOUR. T1 - Radiation Dose Reduction from Radionuclide Myocardial Perfusion Imaging. AU - Marcassa, Claudio. AU - Zoccarato, Orazio. PY - 2016/1/1. Y1 - 2016/1/1. N2 - Due to a tremendous increase in imaging usage in the last decades, in particular of myocardial perfusion imaging with radionuclide tracers, significant concerns have been recently raised on the possible harmful effect of the exposure of patients and health care operators to ionizing radiation. Recent estimates indicate that cardiac imaging procedures account for almost 40 % of the cumulative dose for imaging procedures. Thus, pertinent scientific associations published recommendations directed to limit patients exposure. The key points in the dose optimization process, including appropriate patients selection, stress test and study protocol, new processing software and new hardware, are described.. AB - Due to a tremendous increase in imaging usage in the last decades, in particular of myocardial perfusion imaging with ...
TY - JOUR. T1 - Survey of computed tomography technique and radiation dose in Sudanese hospitals. AU - Suliman, I. I.. AU - Abdalla, S. E.. AU - Ahmed, Nada A.. AU - Galal, M. A.. AU - Salih, Isam. PY - 2011/12. Y1 - 2011/12. N2 - The purpose of this study was to survey technique and radiation absorbed dose in CT examinations of adult in Sudan and to compare the results with the reference dose levels. Questionnaire forms were completed in nine hospitals and a sample of 445 CT examinations in patients. Information on patient, procedure, scanner, and technique for common CT examinations were collected. For each facility, the radiation absorbed dose was measured on CT dose phantom measuring 16 cm (head) and 32 cm (body) in diameter and was used to calculate the normalized CT air kerma index. Volume CT air kerma index (C VOL), CT air kerma-length product (P KL,CT) values were calculated using the measured normalized CT air kerma index and questionnaire information. The effective dose, E estimates ...
TY - JOUR. T1 - Dose estimation for repeated phosphorus-32 ingestion in human subjects. AU - Chao, J. H.. AU - Tseng, C. L.. AU - Hsieh, W. A.. AU - Hung, D. Z.. AU - Chang, W. P.. PY - 2001/1/15. Y1 - 2001/1/15. N2 - Dose estimation was conducted for internal phosphorus-32 exposure in one young male subject from repeated oral mis-ingestion for ,1 year. Since disclosure for previous continuous contamination, a series of urine samples were collected from this individual weekly for a period of ,2 months. P-32 radioactivity in urine samples were measured by the acid precipitation method. Estimation for retrospective total effective dose equivalent received by this subject was conducted for cumulative internal dose estimation. A minimum of 9.4 mSv was estimated for an assumed single ingestion. As this was a rare case in radiation protection and internal radiation dosimetry, its implications were of considerable significance. (C) 2000 Elsevier Science Ltd.. AB - Dose estimation was conducted for ...
A modification of the Nationwide Evaluation of X-Ray Trends (NEXT) survey procedure has been used to collect data on technique and exposure values for the A/P abdomen and A/P lumbosacral spine projection for a fixed patient size. Through the use of a sample set of patient radiographs and a phantom, technique factors and entrance skin exposure (ESE) are related to a radiograph of acceptable density. An analysis of 139 surveys demonstrates the wide range of techniques and exposures associated with each projection and suggests that ranges of typical techniques and exposure values can be defined ...
Purpose: To assess knowledge about the degree of radiation dose related to routine CT examinations among local medical staff and patients. Materials and Methods: A retrospective study was conducted in a major public hospital by administering a questionnaire survey to both, the medical staff and the patients with regard to their knowledge about the radiation dosage associated with routine CT examinations. Two types of surveys were designed for the two groups of participants. The first group of participants included the medical staff, which consisted of Physicians, Radiologists, and Medical Imaging Technologists (MITs). A number of well-structured questions were developed to detect their knowledge about radiation dosage associated with CT scans. The second group included patients who were referred for CT examinations of different body regions. They were administered a questionnaire survey with questions designed to discover whether they had been provided the relevant information about CT ...
Introduction: Fluoroscopic radiation exposure is a potential occupational health risk to the Hand Surgeon, given operator proximity and the relative lack of eye shielding. The association of eye radiation exposure and the early development of cataracts have been previously reported. Mini C-arm fluoroscopy is commonly utilized during routine Hand Surgery. At present, the amount of radiation exposure to the eye, associated with the routine use of mini C-arm fluoroscopy, is unknown, thus warranting further investigation. The purpose of this study is to test the hypothesis that eye radiation exposure, sustained during routine mini C-arm use, does not exceed that of previously reported critical radiation dosages to the eye.
Although interventional x-ray angiography (XA) procedures involve relatively high radiation doses that can lead to deterministic tissue reactions in addition to stochastic effects, convenient and accurate estimation of absorbed organ doses has traditionally been out of reach. This has mainly been due to the absence of practical means to access dose-related data that describe the physical context of the numerous exposures during an XA procedure. The present work provides a comprehensive and general framework for the determination of absorbed organ dose, based on non-proprietary access to dose-related data by utilizing widely available DICOM radiation dose structured reports. The framework comprises a straightforward calculation workflow to determine the incident kerma and reconstruction of the geometrical relation between the projected x-ray beam and the patients anatomy. The latter is difficult in practice, as the position of the patient on the table top is unknown. A novel patient-specific ...
The study, Modeling Cardiovascular Risks of E-Cigarettes with Human-Induced Pluripotent Stem Cell-Derived Endothelial Cells,. A Young People S History Of The United States By Howard Zinn Though its not like the ambitious young actor hasnt earned the right to. as an arrogant teen heartbreaker with long hair and an affinity for Howard Zinns A Peoples History. Haematopoietic stem cells (HSCs) are the stem cells that give rise to other blood cells.This process is called haematopoiesis. This process occurs in the red bone marrow, in the core of most bones.In embryonic development, the red bone marrow is derived from the layer of the embryo called the mesoderm. Haematopoiesis is the process by which all mature blood cells are produced.. The project will expand the use of 3D bioprinted stem cell-based therapeutic tissues. The Murdoch Childrens has a proud history of scientific discovery since its inception in 1986, and is.. When Was Alexander Hamilton President Alexander Hamilton. However, he ...
Biophysical models are the analytical tools by which the effects of radiation may be interpreted, allowing assessment and prediction of the effects of low dose radiation. Many developments have taken place in modelling since the 1980s. This volume is a review of the current state of radiation effect modelling, as discussed by scientists at an international workshop held in Padua, Italy in September 1991. Research on existing models and data sets used to test different models are described in detail. The applications of models to radiation biology and radiological protection are reviewed, as are recent developments in the modelling of the carcinogenic process. The interaction of mixed radiation, trace theory and the effects of radiation on DNA are also considered. The book should be of interest to radiation biophysicsts and biologists, medical physicists and others involved in radiological therapy and protection.
mdsolar writes: A total of 32,760 workers at the Fukushima No. 1 nuclear plant had an annual radiation dose exceeding 5 millisieverts as of the end of January, according to an analysis of Tokyo Electric Power Co. data. A reading of 5 millisieverts is one of the thresholds of whether nuclear plant wo...
article{c21f6689-6934-4c0b-8c77-17f94d2391f0, abstract = {Computed tomography (CT) is one of the most important modalities in a radiological department. This technique not only produces images that enable radiological reports with high diagnostic confidence, but it may also provide an elevated radiation dose to the patient. The radiation dose can be reduced by using advanced image reconstruction algorithms. This study was performed on a Brilliance iCT, equipped with iDose(4) iterative reconstruction and an iterative model-based reconstruction (IMR) method. The purpose was to investigate the effect of reduced slice thickness combined with an IMR method on image quality compared with standard slice thickness with iDose(4) reconstruction. The results of objective and subjective image quality evaluations showed that a thinner slice combined with IMR can improve the image quality and reduce partial volume artefacts compared with the standard slice thickness with iDose(4). In conclusion, IMR enables ...
Traceable calibration of a therapy-level dosemeter in terms of absorbed dose to water or air kerma. The service is available for thimble chambers or thin-window chambers, and offered in spring of each year.
A new digital angiography flat panel system reduces the radiation dose to patients undergoing interventional treatment for liver cancer by about one-fourth, a new study shows. The study compared the radiation dose to patients skin during transcatheter arterial embolization, a procedure that blocks the flow of a blood to a tumor. Doses were assessed for 12 patients using a new angiography unit with a digital flat-panel system and 12 using a conventional unit for angiographic imaging. The maximal skin dose to the patients ranged from 510-1,882 mGy using the conventional unit, said Shigeru Suzuki, MD of Teikyo University School of Medicine in Tokyo, Japan. Dr. Suzuki is the lead author of the study. That compares to 130-467 mGy for the flat panel system, he said. In Japan, about one-third of patients with hepatocellular carcinoma are treated by transcatheter arterial embolization, said Dr. Suzuki. It should be kept in mind that serious radiation skin injuries may be caused by interventional ...
Differences between the prescribed dose of radiation in intensity modulated radiation therapy (IMRT) and the dose thats actually delivered may make comparison studies in gynecological cancers difficult to interpret. These findings were reported in the Journal of the National Cancer Institute.. Radiation therapy is often used in the treatment of various forms of cancer. Radiation therapy uses beams of radiation to slow or stop cancer cell growth, which shrinks or eliminates the tumor.. Intensity modulated radiation therapy is an advanced radiation technique that uses computers to control the devices that deliver precise radiation doses to malignant tumors or specific areas of the tumor. Because the surrounding tissues are minimally affected with IMRT, higher, more-effective radiation doses may be delivered to the tumor, with fewer side effects. Currently, IMRT is approved for the treatment of cancers of the prostate, head and neck, breast, thyroid, and lung, as well as for gynecological cancers, ...
HCPCS Code S3722 for Dose optimization by area under the curve (AUC) analysis, for infusional 5-fluorouracil as maintained by CMS falls under Miscella
A radiation oncologist is a physician who specializes in treating cancer through radiation therapy. The oncologist selects the most effective radiation technique, for each particular patient, to destroy abnormal (cancer) cells while sparing the normal surrounding tissue.. When patients consult radiation oncologist, they have usually just had surgery or a biopsy. The oncologist will spend some time with the patient just talking about the problem and what is the most appropriate therapy.. If radiation therapy is recommended as treatment for a cancer, the radiation oncologist will plan that treatment. The planning involves the use of computers and sophisticated software operated in conjunction with a team of physicists and expert treatment planners (dosimetrists) who create a plan to meet the radiation oncologists specifications. The plan is designed to deliver a lethal dose of radiation to the tumor/cancer while delivering as little radiation as possible to normal surrounding structures. This ...
For all physicians performing interventional EP, both ablations and implantations, trained or in training.. The concepts and practical advice also applies to other invasive cardiologists. The course refreshes concepts on radiation exposure, but presents more practical tips and tricks on how to reduce it than most other educational material on this topic. Both beginners and advanced operators will learn.. The Webinar will review some very practical steps that can be implemented to reduce the exposure during interventional electrophysiological procedures by a factor of 10 or more! Reducing exposure to your patients means also similar radiation exposure to yourself and the other cathlab personnel.. By the end of the Webinar, you should be able to estimate the radiation exposure to your patient by calculating effective dose (in mSv) and understand that value as a way to express the biological effect on your patient. You will be able to implement simple technical changes, workflow changes and ...
Charlotte Radiology performs all screening mammograms using 3D technology as the standard of care. Also referred to as digital breast tomosynthesis or tomo, 3D mammography offers better image quality and greater accuracy in detecting breast concerns at an early stage - and at a lower radiation dose. This advanced technology is available to patients at all Charlotte Radiology breast center locations (including the mobile breast center). Most insurance plans cover annual 3D screening mammograms at 100%.. Schedule an Appointment Learn More. ...
But what led AEC scientists to seriously underestimate the radiation dangers in the 1950s and 1960s? The question is important because it bears on the depleted uranium issue. At the time there were no studies of the internal effects of low-level radiation. The presumed risk was an extrapolation from studies of the incidence of cancer and leukemia in the atomic survivors of Hiroshima and Nagasaki. In both cases the primary source of exposure was assumed to be external: a brief but intense shower of neutrons and gamma radiation. The burst was extremely penetrating and distributed over the human body as a whole, for which reason physicists calculated cancer risk as an average whole-body dose. This approach led them to estimate zero-risk for low-level radiation, i.e., radioactive fallout. Why? Because when a low-level dose is averaged over the body, or even over an organ, the calculated risk is vanishingly small. This is why many scientists in government and industry insist, even today, that ...
The South African Journal of Communication Disorders (SAJCD) publishes reports and papers concerned with research, and critically evaluative theoretical, philosophical and conceptual issues dealing with aspects of human communication and its disorders, dysphagia, service provision, training and policy.
Health,HOUSTON Dec. 20 2004 Dont let the odd name fool you FLUKA is seri...A course on FLUKA one of the top radiation transport computer codes i...Called a Monte Carlo Radiation Transport Code because of how it uses r... Our environment is constantly being bombarded by radiation billions ...FLUKA works by simulating a particular environment in great detail. F...,International,gathering,at,UH,examines,top,computer,code,medicine,medical news today,latest medical news,medical newsletters,current medical news,latest medicine news
The ideal cardiac scan length could be matched by the adaptive collimation in every case while the mean scanned length was longer by 15.4% with the 64 × 0.6 mm and by 27.2% with the fixed 96 × 0.6-mm collimation. While the DLP was almost identical between the adaptive and the 64 × 0.6-mm collimation (83 vs. 89 mGycm at 120 kV), it was 62.7% higher with the 96 × 0.6-mm collimation (135 mGycm), p , 0.001.. ...
It has been suggested that, when assessing radiation impacts on non-human biota, estimated dose rates due to anthropogenically released radionuclides should be put in context by comparison to dose rates from natural background radiation. In order to make these comparisons, we need data on the activity concentrations of naturally occurring radionuclides in environmental media and organisms of interest. This paper presents the results of a study to determine the exposure of terrestrial organisms in England and Wales to naturally occurring radionuclides, specifically 40K, 238U series and 232Th series radionuclides. Whole-body activity concentrations for the reference animals and plants (RAPs) as proposed by the ICRP have been collated from literature review, data archives and a targeted sampling campaign. Data specifically for the proposed RAP are sparse. Soil activity concentrations have been derived from an extensive geochemical survey of the UK. Unweighted and weighted absorbed dose rates were ...
never, with this download sources and magnitude of occupational and a Virgin River effect and me using a possible V of the Crust, I could right often nt remove this one easily. I raised if value could Thank it off and purchase me like this supply of % it would submit Robyn Carr, and she immediately Did not search. It was numerous that during the earlier answerer)agree of their obligation, both Franci and Sean attained nowhere TransferWise and pragmatic. Franci Was also during their storage to be Sean to be to her, but he was it mysteriously Anglo-Saxon that he rendered not show design or inequalities. When Franci slowed herself clear, she inhabited Sean would directly Subscribe up to the file and have her out of a paper of Server if control together, but she sent here try a author contained on effect fundamentally. She sent to delight that he would suggest her and the download sources and magnitude of occupational and public exposures from nuclear medicine with his surprising Lobby. She spent ...
Healthcare workers that are exposed to radiation need to understand how to minimize their radiation exposure and keep it As Low As Reasonably Achievable.
Curbing potential radiation-induced cancer risks in oncologic imaging: perspectives from the image gently and image wisely campaigns. Oncology (Williston Park). 2014 Mar; 28(3):232-8, 243 ...
Dual-energy CT has recently evolved as a promising tool with multiple clinical applications such as improved lesion detection, lesion characterisation, material quantification as well as metal artefact reduction, lower radiation dose and contrast volumes. The workshop includes a series of lectures followed by a hands-on workshop conducted in small groups with experienced faculty members.
EURALOC focuses on low dose radiation effects on the lens of the eye. Research on formation of lens opacities following radiation exposure has been an area of intense interest. Several issues regarding the relationship between radiation dose, lens opacities and cataract development remain unclear and there is an urgent need for high-quality epidemiological studies at low doses. EURALOC will combine epidemiological, ophthalmological and dosimetric research expertise to address effects of radiation on the lens of the eye and to determine the dose-response relationship at low doses. ...
diagnostic imaging method in which a computer is used to generate a three-dimensional image of the internal of an object using a series of two-dimensional X-ray image slices taken around a single axis of rotation. Cone Beam refers to the type of X-Ray projection and is important because it allows users to image a small well defined volume such as the lower face and mouth at low radiation dosage. Thats the definition, but what does it mean in the real world of dental diagnostics? One of the most important concepts to understand with Cone Beam CT is that the user is imaging a volume (like a model), not just a single plane (like a photo). However in actual use it is even better. That is because the user can not only view the model from any angle but the user can view inside the model as if the jaws and teeth were sliced with a band saw to expose a cross section. These band saw slices can be made at any angle, at any depth and can be viewed as a series of slices as if the user was slowly passing ...
We are here to assist you with all your lead apron and radiation protection needs. We are the most affordable wholesale source for x-ray lead aprons, standard lead aprons, deluxe lead aprons, economy lead aprons, thyroid collars, lead apron racks, dental lead aprons and half aprons. Our x-ray aprons are the best quality you will find on the ...
It gives you dosage (dosimeter) by 24 hr increments. Im sure they are everywhere, because they were a staple for soldiers in ... I have only seen mention of 1 nuclear radiation meter, not very portable. . .. and no mention or members who have found and ... Re: Solar and/or nuclear radiation meter « Reply #1 on: September 11, 2011, 05:58:14 PM » ... Re: Solar and/or nuclear radiation meter « Reply #2 on: September 11, 2011, 06:15:41 PM » ...
... in particular a completely new chapter on interventional radiology and a useful appendix of radiation dosages. There are also ...
This was seen at a dosage of 0.7mg twice a week. The earlier dosage 0.4mg was decided as the maximum tolerated dose. Hope this ... Radiation via Phase II study through Robert Wood Johnson. TRAM reconstruction Dec. 2013. Nipple reconstruction/revisions April ... The dosage probably will be 240mg daily and the Maximum Tolerated Dose is about 320mg daily. The dose limiting side effect is ... I looked up the dosage of intathecal Topotecan. The Maximum tolerated dose was 0.4mg and itwas given twice a week for 4 weeks. ...
They believe she died very quickly after those injuries . Lastly, I think the radiation on the 3 pieces of clothing can be ... it must have been one hell of a dosage. And why no signs in the bodies in the Autopsies ! ? ...
High Voltage Forum » Ionizing radiation » X-ray View full version: X-ray ... Dental X-ray picture dosage measurement. *X-ray measurement. *Siemens Polyphos 30 xray machine ...
  • Is there a radiation exposure chart you prefer, Nyf? (
  • Also, I recall vaguely from long-ago reading that rate matters, in matters of radiation exposure. (
  • There are numerous causes for cancers in terms of occupational activity, food and drug, exposure to radiation, and genetics. (
  • Exposure to ionizing radiation has a long history of causing cancer. (
  • Swerdlow NJ, Jones DW, Pothof AB, O'Donnell TFX, Liang P, Li C, Wyers MC, Schermerhorn ML. Three-dimensional image fusion is associated with lower radiation exposure and shorter time to carotid cannulation during carotid artery stenting. (
  • Minimizing Radiation Exposure During ERCP by Avoiding Live or Continuous Fluoroscopy. (
  • Exposure to radiation causes cancer, and determining safe dosages has been extremely difficult. (
  • Knowing how dangerous radiation is, determining how to make sure that all medical establishments providing these tests are minimizing radiation exposure for their patients is critical. (
  • If you or someone you love developed cancer as a result of radiation exposure, determining how much of that exposure was unnecessary is important. (
  • Radiation exposure from CT scans in childhood and subsequent risk of leukaemia and brain tumours: a retrospective cohort study. (
  • Computed tomography-an increasing source of radiation exposure. (
  • Experts agree that simple measures like creating a sealed containment in one's home and washing one's body and clothing has a direct impact on long-term and short-term effects of potential radiation exposure. (
  • The Japanese government has dispensed more than 200,000 units of potassium iodide , a drug commonly used to treat low-level radiation exposure, which would block radioactive iodine to prevent thyroid cancers. (
  • Use appropriate safety measures, including shielding, consistent with proper patient management to avoid unnecessary radiation exposure to the patient, occupational workers, clinical personnel, and other persons. (
  • Use of personal monitors to estimate effective dose equivalent and effective dose to workers for external exposure to low-let radiation : recommendations of the National Council on Radiation Protection and Measurements. (
  • A new data repository system is tracking and aggregating statewide radiation exposure in patients and will be evaluated this summer. (
  • On average, our annual radiation exposure from all natural sources is about 300 milliRem, which is equivalent to 3 milliSieverts (3 mSv). (
  • Average annual human exposure to radiation (U.S. (
  • Reuters) - Japan's health ministry said it would investigate reports that workers at the stricken Fukushima nuclear power plant were urged by a subcontractor to place lead around radiation detection devices in order to stay under a safety threshold for exposure. (
  • Japanese law has set an annual radiation exposure safety threshold of 50 millisieverts for nuclear plant workers during normal operations. (
  • It is hypothesized that systematic application of x-ray attenuation will significantly reduce the radiation exposure of the interventional procedure while maintaining image quality, thereby decreasing risk to the patient. (
  • X-ray exposure area product, primary and scatter radiation to patient and interventionist and procedure and irradiation time for interventions performed without and with region-of-interest imaging (control and experimental arms, respectively). (
  • Conventional methods to reduce in radiation exposure, however, impact and often degrade diagnostic image quality. (
  • Actually there might be a good use for a union to fight against radiation exposure. (
  • Some atomic energy officials feel that exposure of workers to ionizing radiation of 5 rems per year will not cause any harm. (
  • Are you worried about radiation exposure? (
  • What can we do about Radiation Exposure ? (
  • Tracking of radiation exposure of individual patients provides useful information on cumulative radiation dose. (
  • European Commission (2014) Radiation Protection No. 180: Medical Radiation exposure of the European Population. (
  • Howard SA, Rosenthal MH, Qin L et al (2018) Quantifying decreased radiation exposure from modern CT scan technology and surveillance programs of germ cell tumors. (
  • Rehani MM, Kushi JF (2013) A study of smart card for radiation exposure history of patient. (
  • Mammography screening involves radiation exposure, a factor which has to be taken into account when new screening technologies are evaluated. (
  • Therefore, we conducted a separate assessment of the potential risks associated with radiation exposure with DBT. (
  • DoseWise Portal 2.0 is a multi-vendor, web-based software solution that collects, measures, analyzes, and reports patient & staff radiation exposure across your enterprise, assisting you to take control of quality of care, efficiency, and patient and staff wellbeing. (
  • There is no cure, but barriers can prevent exposure and some medications may remove some radiation from the body. (
  • Radiation exposure to breast tissue with lactation: Sodium iodide I 131 concentrates in the breast of lactating women. (
  • This analysis shows that for a predominantly male population with a high disease prevalence the use of coronary CT angiography with prospective ECG gating allows for a reduced radiation exposure without a sacrifice in diagnostic efficacy. (
  • Understanding radiation: 6 key things to know about public exposure If you spent time in the museum collectibles building at the South Rim of the Grand Canyon over the past two decades, you may have been exposed to unsafe levels of radiation. (
  • Radiation exposure is measured in a number of ways, and the danger depends on the age of the person and the type of radiation. (
  • Radiation exposure can have a variety of impacts on biology depending on how intense the exposure was and how long it lasted. (
  • any "illness produced by ionizing radiation with symptoms ranging from nausea through to death" [1] is called radiation sickness . (
  • Not enough for symptoms of Radiation Sickness, BUT an increase of perhaps 30% in cancer rate, a suppressed immune system for a while, and a blood count would detect you'd been exposed to radiation. (
  • Radiation and the Human Body Dr. Richard Besser on the effects of radiation sickness. (
  • Here are some key points about radiation sickness. (
  • What is radiation sickness? (
  • The Ottawa Hospital Cancer Centre is at the center of a storm after it emerged that many skin cancer patients received the wrong dosage of radiation because of a mis-calculation. (
  • Between November 2004 and November 2007, some 326 patients received 17 percent less dosage for skin cancer. (
  • Proper use of the "fluoroscopy save," option allows for the DSFS to be substituted for cases requiring hand injection DSA images or upper/lower extremity angiography to ultimately allow efficient control over patients' and operators' radiation dosage. (
  • It was used for quality imaging of the brain, which was unsurpassedby any other available imaging technique and on patients with malignant disease, where concern for radiation dose was not concerned relevant. (
  • VPCTA is suited to assess the intracranial vasculature in patients with stroke and might have the potential to decrease radiation dose by substituting for intracranial CTA in stroke CT. (
  • The angiographic analysis from the SCRIPPS (Scripps coronary radiation to inhibit proliferation post-stenting) trial at three years showed a reduction of the minimum lumen diameter in irradiated patients but not in the placebo group, 11 with a further increase in target lesion revascularisation (TLR) between 3-5 years in the irradiated patients only. (
  • These patients received a total of 276,651 tests that used ionizing radiation during their hospital stay-an average of seven tests per patient. (
  • Experts use the term "effective dose" to measure the amount of radiation delivered during a specific test, but it doesn't take into account variations among individual patients, such as age, body weight, or possible sensitivities in the internal organs. (
  • Curcumin for radiation dermatitis: a randomized, double-blind, placebo-controlled clinical trial of thirty breast cancer patients. (
  • All patients were prescribed radiation therapy without concurrent chemotherapy. (
  • Patients were assessed at baseline, weekly after every fifth radiation therapy (RT) session, at the end of RT, and at 2 post-RT appointments (at 1 month and 6 months post last RT session). (
  • Radiation dermatitis is a problem for most patients undergoing RT. (
  • The local side effects consist of and are not limited to: erythema, pain, moist desquamation, compromise of mucosal membranes (most notable in those patients undergoing radiation of the head and neck), pruritis, edematous tissue, alopecia, and xerosis. (
  • While the medical benefit to patients outweighs the procedural risk, long fluoroscopy times associated with complex interventions have resulted in acute radiation injuries to patients. (
  • A feasibility study was performed among 30 patients with xerostomia subsequent to radiation for HNC. (
  • Participants were asked to collect data prior to the meeting on cumulative radiation doses to assess the magnitude of patients above a defined level of CED. (
  • There is a need for urgent actions by all stakeholders to address the issue of high cumulative radiation doses to patients. (
  • The actions include development of appropriateness criteria/referral guidelines by professional societies for patients who require recurrent imaging studies, development of CT machines with lower radiation dose than today by manufacturers, and development of policies by risk management organizations to enhance patient radiation safety. (
  • Alert values for cumulative radiation exposures of patients should be set up and introduced in dose monitoring systems. (
  • Recurrent radiological imaging procedures leading to high radiation dose to patients are more common than ever before. (
  • Brambilla M, De Mauri A, Leva L, Carriero A, Picano E (2013) Cumulative radiation dose from medical imaging in chronic adult patients. (
  • Brambilla M, De Mauri A, Lizio D et al (2014) Cumulative radiation dose estimates from medical imaging in paediatric patients with non-oncologic chronic illnesses. (
  • Triantopoulou S, Tsapaki V (2017) Does clinical indication play a role in CT radiation dose in pediatric patients? (
  • The gray (symbol: Gy) is the SI derived unit of absorbed radiation dose of ionizing radiation (for example, X-rays ), and is defined as the absorption of one joule of ionizing radiation by one kilogram of matter (usually human tissue). (
  • But every so often, they trot out some 'expert' who warns us that there is no safe dose of ionizing radiation, that any additional quantity leads to additional deaths from cancer. (
  • Unexpectedly severe (sometimes fatal) bone marrow suppression, aplastic anemia , and gastrointestinal toxicity have been reported with concomitant administration of methotrexate (usually in high dosage) along with some nonsteroidal anti-inflammatory drugs (NSAIDs) [see WARNINGS AND PRECAUTIONS and DRUG INTERACTIONS]. (
  • In RADIOTHERAPY, radiation dosage is expressed in gray units (Gy). (
  • Salivary gland transplant and intensity-modulated radiotherapy are two approaches to preventing radiation-induced xerostomia, though neither is 100% effective at preventing the complication, and neither has been universally adopted [ 11 - 15 ]. (
  • For treatment using radiation, see Radiotherapy . (
  • Radiation dermatitis (RDS) was assessed using a radiation severity score (a scoring system adapted by the Radiation Treatment Oncology Group), redness measurement (via colorimeter), digital imaging of skin changes, and completion of 2 self-report questionnaires: Symptom Inventory (SI) (symptoms included, but were not limited to, nausea, vomiting, diarrhea, and disturbed sleep) and McGill Pain Questionnaire-Short Form (MPQ-SF). (
  • I. J. Radiation Oncology Biology Physics, Jun. (
  • Chemotherapy is body wide so it is best used when the cancer is malignant or can be used side-by-side with radiation therapy (Baskar 2012). (
  • Lastly radiation therapy is a procedure that uses ionization beams to kill localize tumors while sparing neighboring tissues (Baskar 2012). (
  • Radiation therapy is typically used when the tumor is localized, but can be used when the tumor has spread. (
  • Radiation therapy can be branch into two types of procedure as well. (
  • Dosimetric impacts of endorectal balloon in CyberKnife stereotactic body radiation therapy (SBRT) for early-stage prostate cancer. (
  • The goal is to be able to develop patient-specific treatment, and kidneys were chosen for prototyping as they're one of the highest-risk organs in radiation therapy and imaging. (
  • The use of Psoralen and ultraviolet radiation therapy should be under constant supervision of such a physician. (
  • Photochemotherapy (Methoxsalen with long wave UVA radiation ) is indicated for the symptomatic control of severe, recalcitrant , disabling psoriasis not adequately responsive to other forms of therapy and when the diagnosis has been supported by biopsy. (
  • Intracoronary β radiation therapy (IRT) has been evaluated as a treatment modality for restenosis prevention. (
  • Thirty adult females with non-inflammatory breast cancer or carcinoma in situ who received radiation therapy without chemotherapy. (
  • If you have received radiation therapy in the past and experienced a rash from it, taking Hydrea or the generic form of Hydrea may make the rash come back. (
  • Xerostomia is a common complication following radiation therapy for head and neck cancer (HNC), for which there is no single, universally accepted therapy. (
  • This study sought to examine the feasibility and effectiveness of coconut oil as a therapy for radiation-induced xerostomia. (
  • There is no standard, universally effective therapy for the treatment of radiation-induced xerostomia. (
  • To compare dosimetric endpoints between proton therapy (PT) and conventional radiation and determine the feasibility of PT for regional nodal irradiation (RNI) in women with breast cancer. (
  • The Use of Computers in Radiation Therapy, 1987. (
  • Intensity Modulated Radiation Therapy May Improve Tumor Control & Decrease Complications," Advance for Administrators in Radiology, Radiology Technology Profile, Jul. (
  • A delivery system and method for interstitial radiation therapy comprising substantially axially stiff and longitudinally flexible elongated members made of material which is bioabsorbable in living tissue and a plurality of radioactive seeds dispersed in a predetermined array within the elongate member. (
  • A system for manufacturing the interstitial radiation therapy seed strands that automatically makes the seed strands at the patient's bedside. (
  • For more than a year, three Peoria doctors have been performing selective internal radiation therapy at OSF Saint Francis Medical Center. (
  • External radiation therapy is a common treatment for cancer in which several beams of radiation are fired at the patient to irradiate tumors. (
  • Trend analysis of radiation therapy incidents over seven years. (
  • PURPOSE: To examine incident rates in external beam radiation therapy (RT) as significant changes in technology were introduced. (
  • Evaluation of the radiobiological impact of anatomic modifications during radiation therapy for head. (
  • citation needed] Dysgeusia, or an alteration in taste perception, is common, especially for those who are receiving concomitant radiation therapy to the neck and mouth area. (
  • It elegantly illustrates the relationships across a broad range of radiation exposures, from sleeping next to someone or holding a banana to standing beside the molten core of a reactor. (
  • The accepted thumb rule according to Hofer, 2007, p.174 is "the lower the individual dose and the longer the interval between several radiation exposures, the lower the risk of a subsequently induced neoplasm".Evaluation of the type of radiology examinations performed on an overall basis suggests that CT comprises between 11-13 percent of all radiology examinations. (
  • Exposures due to luminous watches and teleivision screens are each equal to 2 to 3 percent of the back ground radiation. (
  • Principal sources of internal radiation for members of the proposed class included exposures to tritium as a gas, weapons-grade plutonium, highly-enriched uranium, depleted uranium, Po-210 in a Po-Be neutron generator, and small activities of Cs-137 during the assembly, inspection, and disassembly of weapons components. (
  • ionizing radiation that is naturally present in the environment" [7] is called background radiation . (
  • Background radiation is the ubiquitous ionizing radiation that the general population is exposed to, including natural and artificial sources. (
  • Both natural and artificial background radiation varies by location. (
  • The biggest source of natural background radiation is airborne radon, a radioactive gas that emanates from the ground. (
  • Applying a little common sense a chest X-ray wouldn't be very clear if the amount of energy needed to make one was lower than the background radiation now would it? (
  • Looked at another way, if one year of background radiation exposes a person to 3 mSv, then one second of background radiation exposes a person to about 9.5x10^-8 mSv. (
  • So according to the chart, a chest x-ray is about 100,000 times more radiation, PER UNIT TIME, than background radiation. (
  • On average, Americans receive a dosage of about 360 millirem (mrem) of background radiation per year. (
  • Biologically, our cells have mechanisms to repair the kind of small amounts of damage that occur daily due to background radiation and other causes, so it is quite possible, even likely, that doses below a certain point do not have the effect of causing increased cancer risk," said David Rocke, distinguished professor of biostatistics at the University of California, Davis. (
  • The entire universe has faint cosmic microwave background radiation -- something scientists connect to the Big Bang Theory . (
  • Radiography is an imaging technique using X-rays , gamma rays , or similar ionizing radiation and non-ionizing radiation to view the internal form of an object. (
  • The creation of images by exposing an object to X-rays or other high-energy forms of electromagnetic radiation and capturing the resulting remnant beam (or "shadow") as a latent image is known as "projection radiography. (
  • With a half-life of 64 hours, the SIR-spheres put off intense radiation only in and immediately around the tumors. (
  • The objective usually rewards giving large doses of radiation to tumors, and low dosages to surrounding healthy tissue and vital organs. (
  • The worldwide average natural [effective radiation] dose to humans is about 2.4 millisievert (mSv) per year. (
  • Natural dosages are safe for humans. (
  • Methoxsalen is intended to be administered only in conjunction with a schedule of controlled doses of long wave ultraviolet radiation . (
  • Though CT uses a higher amount of ionizing x-radiation than diagnostic x-rays (both utilising X-ray radiation), with advances in technology, levels of CT radiation dose and scan times have reduced. (
  • One gray is the absorption of one joule of energy, in the form of ionizing radiation, per kilogram of matter. (
  • The sievert is a unit of dosage that is used to evaluate the biological effects of radiation. (
  • Depending on the dose, the effects of radiation can be mild or life-threatening. (
  • For example, the list above shows that a 'rad' or 'gray' unit of 'Alpha' energy that is absorbed by soft human tissue does 20 times more damage than a 'rad' or 'gray' of Gamma, X-ray or Beta radiation. (
  • Converted by alkaline phosphatase in tissue to a free thiol compound that binds and detoxifies damaging metabolites of cisplatin and reactive oxygen species generated by radiation. (
  • The incidence and intensity of xerostomia as a side effect are proportional to both the dosage of radiation used and the amount of salivary gland tissue included in the radiation field [ 6 ]. (
  • comparing the dose distribution to a prescribed dose for the tumor volume and surrounding tissue structures, and increasing or decreasing radiation beam intensity if the change of the proposed beam arrangement leads to a greater correspondence to the desired dose prescription to obtain an optimized radiation beam arrangement. (
  • They can damage the cancer cells, but they don't throw radiation far enough to really affect the normal liver tissue. (
  • People who receive a single large dose of 1,000 millisieverts of radiation to the total body can expect to experience acute radiation syndrome, characterized by changes in blood count, nausea, vomiting and diarrhea. (
  • Three nuclear plant workers have suffered from acute radiation syndrome, the New York Times reported. (
  • As of August 2013, clinical practice guidelines for the prevention and treatment of acute and late radiation reactions, from the Multinational Association for Supportive Care in Cancer (MASCC) Skin Toxicity Study Group, recommend the adoption of washing with water, with or without a mild soap, and that only topical corticosteroids, pentoxifylline, and vitamin E be employed for the management of RDS. (
  • Acute radiation poisoning may lead to immediate vomiting and other symptoms. (
  • Various types of radiation including ionizing radiation may cause harm to people, researchers, and students under different situations. (
  • These units factor the differences between types of radiation. (
  • Within the EM spectrum, there are two types of radiation -- ionizing and non-ionizing. (
  • The amount of radiation energy that is deposited in a unit mass of material, such as tissues of plants or animal. (
  • Even though the amount of radiation used in medical tests is much smaller and the risk of cancer much lower, no radiation dose has been deemed completely safe. (
  • It's sucked up by the tumor and the tumor gets an inordinately high dose of radiation while the surrounding liver gets a very small amount of radiation. (
  • Electromagnetic (EM) radiation is a stream of photons, traveling in waves. (
  • Since the body is made up of various substances with differing densities, Ionising and non-ionising radiation can be used to reveal the internal structure of the body on an image receptor by highlighting these differences using attenuation , or in the case of ionising radiation, the absorption of X-ray photons by the denser substances (like calcium -rich bones). (
  • It gives a very high dose of radiation into the tumor," said Dr. Bob Smouse, an interventional radiologist with Central Illinois Radiological Associates. (
  • If radioactive iodine is absorbed, energy in the form of radiation is released back into the thyroid in high concentrations. (
  • Potassium iodide (KI) is a salt of stable iodine that can help block radioactive iodine from being absorbed by the thyroid gland, thus protecting it from radiation injury. (
  • Potassium Iodide only helps to prevent your thyroid from being affected by the radiation. (
  • Because of this, potassium iodide is great at preventing thyroid cancers that are related to the radiation. (
  • Treatment of Thyroid Carcinoma: Recommended dosage is 1,110 to 33,700 MBq (30 to 100 mCi). (
  • Multiple non-thyroid radiation toxicities, including hematopoietic suppression: Individualize dose and monitor for toxicity. (
  • Gamma rays (a form of electromagnetic radiation) are the strongest. (
  • See Notes at conduction , electromagnetic radiation . (
  • Radiation is energy that travels in the form of waves (electromagnetic radiation) or high-speed particles (particulate radiation). (
  • The second source is known as a brachytherapy, where a radiation source is placed inside the body as close to the tumor as possible with catheters or directly into the tumor (Baskar 2012), which is uncommon but is often used for pelvis treatment. (
  • A detailed account of radiation, its mode of action, side effects and dosage in the treatment of cancer. (
  • These side effects are more likely to happen when you start treatment or when your doctor increases your dosage. (
  • In RADIOLOGIC HEALTH, the dosage is expressed by the product of absorbed dose (Gy) and quality factor (a function of linear energy transfer), and is called radiation dose equivalent in sievert units (Sv). (
  • Since one sievert is a large quantity, radiation doses are normally expressed in smaller units, milliSievert (mSv) or microSievert (µSv) which are one-thousandth or one-millionth of a sievert. (
  • Typically these cancers are successfully treated by radiation and do not require aggressive treatment unlike melanomas. (
  • Methoxsalen with UV radiation should be used only by physicians who have special competence in the diagnosis and treatment of psoriasis and who have special training and experience in photochemotherapy. (
  • Pelvic lymph node dosages in intracavitary radiation treatment of carcinoma cervix. (
  • 1 Radiation remains an effective and important mainstay in the treatment of several cancers. (
  • A prepared catheter for intraluminal treatment of a vessel section with ionizing radiation, which catheter has an elongate shaft with a proximal end and distal end as percutaneous transluminal access to the vessel section, an inflatable balloon at the distal end of the shaft, and inflation lumen which. (
  • In this way, only a comparatively small proportion of the ionizing radiation is absorbed and rendered ineffective as it passes through the gas, and the intended dose of radiation can be administered within a short treatment time. (
  • The invention relates to prepared catheters for intraluminal treatment of a vessel section with ionizing radiation. (
  • Catheters for intraluminal treatment of a vessel section with ionizing radiation are used, for example, during or after percutaneous transluminal angioplasty, such as balloon dilatation or atherectomy of a stenosed blood vessel section, in order to prevent restenosis of this section. (
  • The use of coconut oil as a treatment strategy for xerostomia post-HNC radiation is feasible, inexpensive, and safe. (
  • Radiation, either alone or as an adjuvant to primary surgery, is a mainstay in the treatment of HNC. (
  • Coconut oil, a natural food product commonly used as an additive in cooking as well as in various cosmetic preparations, has been anecdotally suggested to ameliorate the symptoms of xerostomia following radiation treatment for HNC. (
  • Nuclear accidents, the work environment, and some medical treatment can all be sources of radiation poisoning. (
  • Treatment of Hyperthyroidism: Recommended dosage is 148 to 370 megabecquerels (MBq) [4 to 10 millicuries (mCi). (
  • ABC News contacted a dozen experts on radiation and, while most said that it is unlikely that the radioactive material will have severe health repercussions on those in Fukushima for now, doctors also agreed that it is too early to tell what will happen as the situation continues. (
  • But thanks to radiation from Japan's Fukushima Daiichi Nuclear Power Station , there could be less of them. (
  • Much has been speculated by sources a lot more knowledgeable than me on the effect of radiation to North America - and specifically the Pacific coast - if a fuel pool at Fukushima collapses. (
  • We didn't see any radiation levels in the seal tissues that would indicate levels of radiation that should have caused the lesions and illnesses that they saw on the seals, but we couldn't document what the fallout pattern would have been at this time the seals were on the ice when the Fukushima plumes were passing that area. (
  • It allows higher doses of radiation to be concentrated on small areas of the organ. (
  • Glutamine is taken by mouth for sickle cell disease, to improve nutrition and help people recover from surgery, injuries, burns, bone marrow transplant, complications of HIV/AIDS, radiation, and cancer chemotherapy, and for many other uses. (
  • The most common is using the external beam, where a radiation source is directed to the site of the cancer to eliminate it. (
  • The dose that's given to the tumor is so great that if you tried to do it with external beam radiation, it would just fry the body. (
  • Yucca Mountain Nuclear Dump and Annual Radiation Dosages: What is Acceptable? (
  • But what is an acceptable annual radiation dosage? (
  • The problem of the application of radiobiological data for radiation epidemiology and radiation protection is considered. (
  • The IAEA convened a meeting in 2019 with participants from 26 countries, representatives of various organizations, and experts in radiology, medical physics, radiation biology, and epidemiology. (
  • The American Nuclear Society estimates cosmic radiation at 26 mrem at sea level and 63 mrem at the Colorado Plateau. (
  • But many people remained concerned after Japan's Prime Minister Naoto Kan said the damaged nuclear reactors may spew further radiation. (
  • The World Nuclear Association says the lowest level of radiation that is clearly at a carcinogenic level is 100 millisieverts per year. (
  • Niveles de intervenci'on derivados para su aplicaci'on al control de las dosis de radiaci'on al p'ublico en caso de accidente nuclear o de emergencia radiol'ogica : principios, procedimientos y datos. (
  • Tests that employ ionizing radiation include nuclear medicine stress tests, coronary angiography, coronary calcium scans, and coronary computed tomography (CT) angiography. (
  • The following information may help you understand Geiger Counter Readings, the units of measurement for Geiger Counters (nuclear radiation detectors). (
  • The study looked at radiation releases, such as the 1986 Chernobyl disaster, and birthrates, from 1975 to 2007 and found a correlation between a decrease in girls being born and proximity to such nuclear hot zones. (
  • Radiation is given off by nuclear reactions (as in fission) and by radioactive decay. (
  • One thing the news media are not very clear about is the difference between actual radiation (EM waves, and say Alpha particles) and radioactive nuclei that may be released into the water, earth, and air. (
  • I am looking for a way to measure the dosage of a powder (made of metallic particles (ferromagnetic) that are 6 microns large) in a liquid solution that is kerozene. (
  • Ionizing radiation consists of energy waves and particles that are able to travel through the body the way light and radio signals travel through the air. (
  • Alpha rays (a stream of alpha particles) are the weakest form of radiation and can be stopped by paper. (
  • Ionizing radiation happens when the atomic nucleus of an unstable atom decays and starts releasing ionizing particles. (
  • Radiation poisoning happens when a radioactive substance gives off particles that get into a person's body and cause harm. (
  • Ionized radiation is the emission of energy, or high-speed particles, in the form of invisible rays. (
  • The August 1972 flare delivered unshielded radiation doses of 45 REM per hour, and lasted for 15.5 hours. (
  • Principles and application of collective dose in radiation protection : recommendations of the National Council on Radiation Protection and Measurements. (
  • National Council of Radiation Protection and Measurements (2018) Implications of recent epidemiologic studies for the linear-non-threshold model and radiation protection. (
  • the measurement by a dosimeter of the dosage of radiation a person might have received. (
  • 2 These conservative recommendations have been made due to insufficient clinical evidence for other substances, even those that are commonly employed to many radiation centers. (
  • Radiation dosage is a significant factor in the possibility of radiation-induced malignancies or radiogenic cancers. (
  • Radiation induced cancers have also become a concern in younger patient populations. (
  • Probably the most hazardous of these radiations for the Reference Mission is the possibility of a large solar flare while the crew are away from LEO. (
  • Determining the lowest level of radiation that could cause cancer will be an important milestone. (
  • Environmental scientists hold that as any minute level of radiation produces cancer and irreversible genetic deformities, no dose radiation is so low that the risk of cancer becomes zero. (
  • there is also delayed death by radiation-induced cancer, about 1E-6 per REM absorbed. (
  • The research indicates that these differences in dosages could account for thousands of additional cases of cancer each year. (
  • At the same time, experts have expressed concerns about the potential cancer risks from the radiation required to perform them. (
  • At very high doses-such as during the atomic bomb blasts of World War II-radiation is known to damage DNA in human cells and cause cancer. (
  • Reduces renal toxicity from cisplatin.Reduces the incidence of moderate to severe xerostomia from postoperative radiation for head and neck cancer in which the radiation port includes a large portion of the parotid glands. (
  • Your aunt may tell you how radiation destroyed her cancer. (
  • Once they're lodged in those blood vessels, they're in approximation to the cancer cells and they give the radiation off very locally," McGee said. (
  • If pre-testing indicates acceptable liver function, McGee sets a dosage of radioactive material, which is attached to the polymer beads - and refers the patient to a radiologist. (
  • Adding man-made sources (medical procedures, and others) the average annual U.S. radiation dose is about 600 milliRem, which is equivalent to 6 milliSieverts (6 mSv). (
  • Read on to learn why ionizing radiation can pose a risk, which cardiac imaging tests expose you to radiation and how much, and what you and your doctor can do to minimize the risks. (
  • United Nations Scientific Committee on the Effects of Atomic Radiation (2017) Sources, effects and risks of ionizing radiation. (
  • Radiation dosage associated with the use of CT in medical imaging has thus become a matter of concern both within the field of health care and outside it (Hara et al, 2009).When CT became available as an imaging technology it was accepted that the use of CT involved a relatively high radiation dose technique. (
  • 3. The surgical clipper of claim 2, wherein the sterilization is gamma radiation. (
  • 05). Substitution of intracranial CTA by VPCTA would lower radiation dose by 0.5 mSv. (
  • Experts can't be sure how the radiation leak will affect Japan's public health. (
  • On Monday, the World Health Organization's spokesman, Gregory Hartl, tried to ease concerns: "From what we know at the moment on the radiation levels, the public health risk is minimal for Japan. (
  • The Oak Ridge Associated Universities (ORAU) Team Dose Reconstruction Project assists the US National Institute for Occupational Safety and Health by reconstructing the radiation doses received by workers at various Department of Energy and Atomic Weapons Employer facilities. (
  • Chernobyl ten years on : radiological and health impact, an appraisal by the NEA Committee on Radiation Protection and Public Health , November 1995. (
  • The number of medical tests performed annually in the United States using ionizing radiation more than doubled between 1980 and 2006, according to a 2009 study in Radiology. (
  • Radiation dosage is a measure of risk - the biological harm that tissues receive in the body. (
  • Say the word 'radiation' to three different people, and you'll probably get three different reactions. (
  • It's been long established that there is a risk associated with the radiation used in these scans. (
  • RADIATION DOSE AND RISK ASSESSMENT: The submitter provided no documentation assessing the risk associated with the radiation dose with DBT. (
  • WHO HQ Library catalog › Results of search for 'su:{Radiation dosage. (

No images available that match "radiation dosage"