Читать книгу A Comprehensive Guide to Radiographic Sciences and Technology - Euclid Seeram - Страница 27

Radiographic imaging includes modalities such as DR, DF, and CT. There are several technical factors including operator‐selectable (under the control of the technologist and/or radiologist) factors that affect the dose to the patient and operator. The major factors affecting dose to the patient in DR include beam energy and filtration, exposure technique factors, beam collimation, the size of the x‐ray field, the size of the patient, SID, grids, image receptor sensitivity or speed, and DQE. Major technical factors affecting the dose to the patient in fluoroscopy include beam energy or filtration, x‐ray tube current, beam‐on time, automatic dose‐rate control, collimation, source‐to‐skin distance, patient‐to‐image intensifier distance, patient size, anti‐scatter grids, image magnification, last image hold, image recording method, and pulsed fluoroscopy.

In CT, there are numerous technical factors affecting the dose to patients. Major factors include exposure technique factors, pitch, effective mAs, collimation and slices, overbeaming and overranging, automatic tube current modulation, automatic voltage selection, and IR algorithms.