Pediatric nuclear medicine, Part II: Common procedures and considerations.
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OBJECTIVE: This paper introduces technologists to pediatric nuclear medicine applications as well as serves as a review of the principles of pediatric imaging for more experienced technologists. After reading this article the nuclear medicine technologist should be able to: (a) identify pediatric populations commonly evaluated with nuclear medicine procedures; (b) state the indications for performing pediatric nuclear medicine procedures; and (c) discuss strategies and tips for performing nuclear medicine procedures on pediatric patients. (+info)
Nuclear pharmacy, Part II: Nuclear pharmacy practice today.
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OBJECTIVE: Nuclear pharmacy is a specialty within the profession of pharmacy that focuses on the proper use of radiopharmaceuticals. This article reviews various features of contemporary nuclear pharmacy practice. After reading this article the nuclear medicine technologist should be able to: (a) describe nuclear pharmacy training and certification; (b) discuss nuclear pharmacy practice settings; (c) discuss nuclear pharmacy practice activities; (d) list professional organizations; and (e) describe activities associated with job satisfaction. In addition, the reader should be able to discuss regulatory issues of current concern. (+info)
The influence of flood source placement on radiation exposure during quality control testing.
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OBJECTIVE: This study examined the photon energy distribution and exposure rate from a 250-MBq 57Co flood source during quality control (QC) procedures as a function of source placement and measurement location. The optimum placement of the source to reduce the radiation dose to the nuclear medicine technologist during QC checks was determined. METHODS: Measurements of exposure rate were made inside and outside a camera room with the source positioned either above or below the camera head. The energy distribution of the photon field was examined at the same locations using a high-resolution gamma-ray spectrometer. Additional measures of exposure rate were made with the source at various distances from the camera face. RESULTS: The lowest exposure rates occurred when the source was lying directly on the face of the camera head. The exposure rates at locations inside the camera room increased by a factor of 4.3 +/- 3.0 when the source was placed on an imaging table below the camera head. This increase can be attributed to decreased shielding provided by the camera head. CONCLUSION: A large portion of the radiation dose received by technologists during QC checks is due to scattered radiation and x-rays produced by gamma-ray interactions within the camera. This dose can be reduced significantly if QC checks are performed with the flood source lying directly on the inverted gamma camera head rather than placing the flood source on an imaging table under the gamma camera. (+info)
Is your technetium generator eluate sterile?
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OBJECTIVE: This study was performed to assess the sterility of multidose 99mTc generator eluate vials at the end of a working day. METHODS: Expired 99mTc generator eluate vials were collected over a period of 10 wk and stored until the activity reached background. Four batches of 10 vials each were selected randomly and sent to an independent microbiology laboratory for sterility testing. RESULTS: No eluate showed any microbial growth after 14 d incubation in growth media. CONCLUSION: Retrospective sterility testing of 99mTc generator eluate confirmed the validity of our departmental protocol for radiopharmaceutical preparation. Sterility testing has become part of our quality control program. (+info)
Radiology workflow and patient volume: effect of picture archiving and communication systems on technologists and radiologists.
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This study was performed to evaluate the changes in workflow and efficiency in various clinical settings in the radiology department after the introduction of a picture archiving and communication system (PACS). Time and motion data were collected when conventional image management was used, and again after the introduction of a PACS. Changes in the elapsed time from examination request until the image dispatch to the radiologist, and from dispatch until report dictation, were evaluated. The relationship between patient volume and throughput was evaluated. The time from examination request until dispatch was significantly longer after the introduction of PACS for examinations taken on patients from the emergency department (ED) (pre-PACS, 20 minutes; post-PACS, 25 minutes; P < .0001), and for examinations taken on patients in the medical intensive care unit (MICU) (pre-PACS, 34 minutes; post-PACS, 42 minutes; P < .0001). The interval from image dispatch until report dictation shortened significantly after the introduction of PACS in the ED (pre-PACS, 38 minutes; post-PACS, 23 minutes; P < .0001) and in the outpatient department (OPD) (pre-PACS, 38 minutes; post-PACS, 20 minutes; P < .0001). Simple least squares regression showed a significant relationship between daily patient volume and the daily median time until report dictation (F = 43.42, P < .001). PACS slowed technologists by prolonging the quality-control procedure. Radiologist workflow was shortened or not affected. Efficiency is dependent on patient volume, and workflow improvements are due to a shift from batch to on-line reading that is enabled by the ability of PACS to route enough examinations to keep radiologists fully occupied. (+info)
A new needle-crystalline computed radiography detector.
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The most successful digital radiography detectors to date have been storage phosphor plates used in computed radiography (CR). The detector is cheap, has good producibility, and is robust. Direct radiography (DR) systems are being developed based on flat-panel technology. Better image quality is claimed for some DR systems. On the other hand, DR detectors have low producibility and robustness, and a high price. A new CR detector is being developed at Agfa that combines the advantages of CR and DR. It is a storage phosphor plate made up of needle-shaped crystals. The phosphor efficiently converts absorbed x-ray quanta into photostimulable centers for efficient read out. It has a large dynamic range and its emission is efficiently detected with both photomultiplier tube (PMT) and charge coupled device (CCD). It is shown that CR systems based on the new detector offer image quality that matches that of the best DR systems. (+info)
Reading chest radiographs for pneumoconiosis by computer.
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Computer programs for measuring simple pneumoconiosis in radiographs are described and assessed. The 36 films studied had been read by 11 skilled human observers and a 'radiological score' of pneumoconiotic severity was therefore available for each film. The computer assigns to each square grid of side 3-6 mm a measure which reflects the unevenness of the density distribution in that grid. The 'computed score' is defined as the mean diversity over all relevant grids in both lung fields. On the set of 36 films the correlation between radiological score and computed score was 0-88. By contrast, the correlation between the score assigned by a single observer and the average of the scores assigned by the other 10 was in the range 0-95 to 0-98. The program can use the computed score to classify a film into one of the four major International Labour Office (ILO) U/C categories, the success rate of this process being 80% compared with those quoted by other workers in the range 45%-65%. If the films used in this study be typical, then the program described may form the basis of an automatic method for measuring pneumoconiosis in epidemiological work. (+info)
SPECT in the year 2000: basic principles.
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OBJECTIVE: SPECT has become a routine procedure in most nuclear medicine departments. SPECT provides significant technical challenges for the nuclear medicine technologist, as compared with planar imaging, in the areas of SPECT acquisition, image reconstruction, and data processing. Many new advances in SPECT methodology are becoming available, such as iterative reconstruction, multimodality fusion, and advanced gated cardiac SPECT. SPECT imaging is demanding and requires careful attention to proper acquisition protocols, whether circular or noncircular orbits, and postprocessing is becoming more complex with the addition of iterative reconstruction and attenuation correction algorithms, among others. Understanding the principles of SPECT is essential not only to produce the highest quality scans but also to identify image artifacts. After reading this article, the nuclear medicine technologist should be able to: (a) describe the historical development and benefits of SPECT imaging; (b) state the impact of image matrix size, number of projections, and arc of rotation on final SPECT image quality; (c) discuss the trade-offs between image noise content and spatial and contrast resolution in SPECT reconstruction; (d) discuss SPECT filters and their impact on image quality; (e) explain the differences between filtered backprojection and iterative reconstruction; and (f) describe the impact of attenuation and scatter in SPECT imaging and the advantages and pitfalls of attenuation correction methods. (+info)