Why and how is soft copy reading possible in clinical practice?
The properties of the human visual system (HVS) relevant to the diagnostic process are described after a brief introduction on the general problems and advantages of using soft copy for primary radiology interpretations. At various spatial and temporal frequencies the contrast sensitivity defines the spatial resolution of the eye-brain system and the sensitivity to flicker. The adaptation to the displayed radiological scene and the ambient illumination determine the dynamic range for the operation of the HVS. Although image display devices are determined mainly by state-of-the-art technology, analysis of the HVS may suggest technical characteristics for electronic displays that will help to optimize the display to the operation of the HVS. These include display size, spatial resolution, contrast resolution, luminance range, and noise, from which further consequences for the technical components of a monitor follow. It is emphasized that routine monitor quality control must be available in clinical practice. These image quality measures must be simple enough to be applied as part of the daily routine. These test instructions might also serve as elements of technical acceptance and constancy tests. (+info)
Radiation dose to patients and personnel during intraoperative digital subtraction angiography.
BACKGROUND AND PURPOSE: The use of intraoperative angiography to assess the results of neurovascular surgery is increasing. The purpose of this study was to measure the radiation dose to patients and personnel during intraoperative angiography and to determine the effect of experience. METHODS: Fifty consecutive intraoperative angiographic studies were performed during aneurysmal clipping or arteriovenous malformation resection from June 1993 to December 1993 and another 50 from December 1994 to June 1995. Data collected prospectively included fluoroscopy time, digital angiography time, number of views, and amount of time the radiologist spent in the room. Student's t-test was used to assess statistical significance. Effective doses were calculated from radiation exposure measurements using adult thoracic and head phantoms. RESULTS: The overall median examination required 5.2 minutes of fluoroscopy, 55 minutes of operating room use, 40 seconds of digital angiographic series time, and four views and runs. The mean room time and the number of views and runs increased in the second group of patients. A trend toward reduced fluoroscopy time was noted. Calculated effective doses for median values were as follows: patient, 76.7 millirems (mrems); radiologist, 0.028 mrems; radiology technologist, 0.044 mrems; and anesthesiologist, 0.016 mrems. CONCLUSION: Intraoperative angiography is performed with a reasonable radiation dose to the patient and personnel. The number of angiographic views and the radiologist's time in the room increase with experience. (+info)
Patient education in nuclear medicine technology practice.
This is the second article of a two-part series on patient education. This article builds on the first one by discussing some of the unique considerations in providing patient education in the nuclear medicine department. Concrete strategies for nuclear medicine technology practice are discussed here. After reading this article, the technologist should be able to: (a) describe the affective and technical aspects of the nuclear medicine technologist's role as a patient educator; (b) identify some strategies that nuclear medicine technologists can use to become better teachers; and (c) describe factors that affect patient learning in the nuclear medicine department and some approaches to overcome or minimize learning barriers. (+info)
Practical aspects of radiation safety for using fluorine-18.
The use of positron-emitting nuclides is becoming routine in nuclear medicine departments today. Introducing these nuclides into the nuclear medicine department can be a smooth transition by instituting educational lectures, radiation safety protocols and patient education. The radiation safety concerns of the technical staff, physicians and ancillary personnel are important and must be addressed. Nuclear medicine departments can be optimistic about implementing PET imaging while staying well within ALARA guidelines. After reading this article, the technologist should be able to: (a) describe at least three ways to reduce the radiation dose to the technologist during the performance of PET imaging procedures with 18F; (b) discuss the relationships between gamma-ray energy, the amount of activity administered to a patient, exposure time and occupational dose; and (c) describe one strategy to minimize the radiation dose to the bladder in patients who have received 18F. (+info)
Assessing the use of nuclear medicine technology in sub-Saharan Africa: the essential equipment list.
OBJECTIVE: The primary aim of the survey was to determine the core equipment required in a nuclear medicine department in public hospitals in Kenya and South Africa, and evaluate the capital investment requirements. METHODS: Physical site audits of equipment and direct interviews of medical and clinical engineering professionals were performed, as well as examination of tender and purchase documents, maintenance payment receipts, and other relevant documents. Originally, 10 public hospitals were selected: 6 referral and 4 teaching hospitals. The 6 referral hospitals were excluded from the survey due to lack of essential documents and records on equipment. The medical and technical staff from these hospitals were, however, interviewed on equipment usage and technical constraints. Data collection was done on-site and counter-checked against documents provided by the hospital administration. RESULTS: A list of essential equipment for a nuclear medicine department in sub-Saharan Africa was identified. Quotations for equipment were provided by all major equipment suppliers, local and international. CONCLUSION: A nuclear medicine department requires eight essential pieces of equipment to operate in sub-Saharan Africa. Two additional items are desirable but not essential. (+info)
Cancer mortality among radiological technologists in Japan: updated analysis of follow-up data from 1969 to 1993.
A retrospective cohort study was conducted for 12,195 male radiological technologists who received the occupational exposure to low dose radiation over a long term. A total of 1,097 deaths including 435 from cancer were ascertained by Koseki and death certificates from 1969 to 1993. Cancer mortality among the study population was basically compared with that of whole Japanese men. The significant low SMRs were obtained for all cancers, stomach and lung cancer partly due to Healthy Worker Effect, unlike the results of the early reports with some inappropriateness in the methods. Apparent high risks of lymphatic and hematopoietic cancers were observed, although none of site-specific cancers revealed the statistically significant increase. For these cancers, the SMRs among old sub-cohort were somewhat higher than those of young sub-cohort, whereas similar SMRs for solid cancer were obtained between the two sub-cohorts. The SMR for leukemia reached statistically significant level of 1.75 (95% CI: 1.07-2.71) when using whole professional and technical workers as a standard population. The study results might suggest that the chronic exposure to low-dose radiation enhanced the risk of lymphatic and hematopoietic cancers. (+info)
Challenges associated with the incorporation of digital radiography into a picture archival and communication system.
Digital radiography (DR) has recently emerged as an attractive alternative to computed radiography (CR) for the acquisition of general radiographic studies in a digital environment. It offers the possibility of improved spatial and contrast resolution, decreased radiation dose due to improved efficiency of detection of x-ray photons, and perhaps most importantly, holds out the promise of increased technologist productivity. To achieve maximum efficiency, DR must be completely integrated into existing information systems, including the hospital and radiology information systems (HIS/RIS) and, when present, the picture archival and communication system (PACS). The early experience with the integration of DR at the Baltimore Veterans Affairs Medical Center (VAMC) has identified several challenges that exist to the successful integration of DR. DR has only recently been defined as a separate Digital Imaging and Communications in Medicine (DICOM) modality and images obtained will, at first, be listed under the category of CR. Matrix sizes with some DR products on the market exceed the current size limitations of some PACS. The patient throughput may be substantially greater with DR than with CR, and this in combination with the larger size of image files may result in greater demands for network and computer performance in the process of communication with the HIS/RIS and PACS. Additionally, in a hybrid department using both CR and DR, new rules must be defined for prefetching and display of general radiographic studies to permit these examinations to be retrieved and compared together. Advanced features that are planned for DR systems, such as dual-energy subtraction, tomosynthesis, and temporal subtraction, will likely require additional workstation tools beyond those currently available for CR. (+info)
The importance of a picture archiving and communications system (PACS) manager for large-scale PACS installations.
Installing a picture archiving and communication system (PACS) is a massive undertaking for any radiology department. Facilities making a successful transition to digital systems are finding that a PACS manager helps guide the way and offers a heightened return on the investment. The PACS manager fills a pivotal role in a multiyear, phased PACS installation. PACS managers navigate a facility through the complex sea of issues surrounding a PACS installation by coordinating the efforts of the vendor, radiology staff, hospital administration, and the information technology group. They are involved in the process from the purchase decision through the design and implementation phases. They can help administrators justify a PACS, purchase and shape the request for proposal (RFP) process before a vendor is even chosen. Once a supplier has been selected, the PACS manager works closely with the vendor and facility staff to determine the best equipment configuration for his or her facility, and makes certain that all deadlines are met during the planning and installation phase. The PACS manager also ensures that the infrastructure and backbone of the facility are ready for installation of the equipment. PACS managers also help the radiology staff gain acceptance of the technology by serving as teachers, troubleshooters, and the primary point-of-contact for all PACS issues. This session will demonstrate the value of a PACS manager, as well as point out ways to determine the manager's responsibilities. By the end of the session, participants will be able to describe the role of a PACS manager as it relates to departmental operation and in partnership with equipment vendors, justify a full-time position for a PACS manager, and identify the qualifications of candidates for the position of PACS manager. (+info)