Digital radiographicimagingsystems, such as those using photostimulable storage phosphor, amorphous selenium, amorphous silicon, CCD, and MOSFET technology, can produce adequate image quality over a much broader range of exposure levels than that of screen/film imagingsystems. In screen/film imaging, the final image brightness and contrast are indicative of over- and underexposure. In digital imaging, brightness and contrast are often determined entirely by digital postprocessing of the acquired image data. Overexposure and underexposures are not readily recognizable. As a result, patient dose has a tendency to gradually increase over time after a department converts from screen/film-based imaging to digital radiographicimaging. The purpose of this report is to recommend a standard indicator which reflects the radiation exposure that is incident on a detector after every exposure event and that reflects the noise levels present in the image data. The intent is to facilitate the production of consistent, high quality digital radiographicimages at acceptable patient doses. This should be based not on image optical density or brightness but on feedback regarding the detector exposure provided and actively monitored by the imagingsystem. A standard beam calibration condition is recommended that is based on RQA5 but uses filtration materials that are commonly available and simple to use. Recommendations on clinical implementation of the indices to control image quality and patient dose are derived from historical tolerance limits and presented as guidelines.
II. DEFINITION OF TERMS USED
IV. STANDARD RADIATION EXPOSURE CONDITIONS
IV.A. Standard beam spectrum
IV.B. Standard beam geometry and calibration verification procedure
V. ASSESSMENT OF INDICATED EQUIVALENT AIR KERMA
VI. REPORTING DEVIATION INDEX
VII. CLINICAL USE OF THE DEVIATION INDEX
VIII. EXPOSURE INDICATOR AND RADIOGRAPHIC TECHNIQUES
IX. AND AUTOMATIC EXPOSURE CONTROL SYSTEMS
X. INAPPROPRIATE CLINICAL USE OF DI
XI. RECOMMENDED OPTIONAL FEATURES
XII. APPLICATION TO DEDICATED CHEST, MAMMOGRAPHY, VETERINARY, AND DENTAL RADIOGRAPHY
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