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. - MarketResearchReports.biz
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; ...
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 - http://vbs.rs/scripts/cobiss?command=DISPLAY&base=70036&RID=50768655 UR - http://nardus.mpn.gov.rs/123456789/10352 UR - http://vet-erinar.vet.bg.ac.rs/handle/123456789/46 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 ifreebudget.com/lipo-flavonoid-plus-reviews.html. 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, ...
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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
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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 ...
CHICAGO - Is radiology making progress in reducing the radiation dose used...Read more on AuntMinnie.comRelated Reading: Video from RSNA 2019: Whats happening with MRI safety Video from RSNA 2019: Dr. Paul Chang on AI and radiology Video from RSNA 2019: Vaping and lung disease JAMA: Medical imaging use rates continue to rise CT radiation dose levels vary widely, new study finds...
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 - http://www.scopus.com/inward/record.url?scp=78649648606&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=78649648606&partnerID=8YFLogxK. 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 ...
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 ...
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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.
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 ...
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A lot of research has been undertaken on the effects of low-level radiation. The findings have failed to support the so-called linear no-threshold (LNT) hypothesis. This theory assumes that the demonstrated relationships between radiation dose and adverse effects at high levels of exposure also applies to low levels and provides the (deliberately conservative) basis of occupational health and other radiation protection standards.. Increasing evidence suggests that there may be a threshold between 100 and 700 mSv below which no harmful effects of radiation occur without effective cellular repair. However, this is not yet accepted by national or international radiation protection bodies as sufficiently well-proven to be taken into official standards. Nevertheless, at low levels of exposure, the bodys natural mechanisms do repair radiation and other damage to cells soon after it occurs, and some adaptive response is stimulated which protects cells and tissues, as with exposure to other external ...
Chronic Low Dose Rate Ionizing Radiation Exposure Induces Premature Senescence in Human Fibroblasts that Correlates with Up Regulation of Proteins Involved in Protection against Oxidative Stress. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.