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Data SummariesEach year the NEXT survey program selects a particular radiological examination for study and collects radiation exposure data from a nationally representative sample of U.S. clinical facilities. Surveys are repeated periodically to track trends as technology and clinical practices change. Since 1973, NEXT has been conducting surveys on examinations related to the adult chest, abdomen, lumbosacral (LS) spine, upper gastrointestinal fluoroscopy, mammography, computed tomography, dental radiography, and pediatric chest radiography. The following is a breakdown by year of the NEXT surveys that have been performed and the corresponding number of facilities surveyed:NEXT Surveys Performed
*As of 8/03 The NEXT surveys today capture comprehensive data on radiation exposure and image quality associated with the practice of medical diagnostic radiology. Among the data obtained are the evaluations of film processing quality, the integrity of the film processing darkroom environment, x-ray film-image quality, and information about the facility's general practice. The following are data summary tables for the NEXT exams that have been performed: Adult Chest Exam
Abdomen Exams
*Preliminary Lumbosacral Spine Exams
*As of 8/03 Fluoroscopy- Upper GI Exam and Special Topics
*Copper is used to simulate the presence of barium contrast Pediatric Chest Exam
Dental (Intraoral) Exam
Computed Tomography Head Exam (axial scanning)
Body Exams (helical scanning) - Effective Dose (mSv)
Darkroom Fog and Film Processing Darkroom fog is a measure of optical density on clinical radiographs that results from ambient light conditions in the darkroom. Darkroom fog can result from light leaks, improper safelight conditions from the use of inappropriate bulbs or damaged filters, and from inadvertent exposure during film storage or handling. The quality of film processing is evaluated by a procedure known as the "Sensitometric Technique for the Evaluation of Processing" or STEP. This test utilizes a selected control batch of radiographic film with a pre-determined sensitometric curve when processed according to film manufacturer recommendations. The control film is flashed by a sensitometer and then processed the same way as film is processed normally at the facility. A comparison is made of the optical densities obtained at the facility with what should be obtained were the control film processed as required by the film manufacturer. Any deviation of the control film optical density produced at the facility from what should be obtained were the facility processing according to the "gold standard" determines the extent of under- or over-processing of the film by the facility. The resulting processing speed value is then determined, with a speed range of 80 to 120 considered acceptable for standard cycle processing. Under processing, which corresponds to a processor speed value of below 80, is an inefficiency that maybe inappropriately compensated with increased radiation exposure to patients. The following is an overall survey comparison of Film Processing and Darkroom Fog:
*Results are from MQSA inspections **The range of acceptable processing speed is 80 to 120 (standard cycle), and 100-130 (extended cycle) Updated May 11, 2007 |
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