How does the Exposure Index provide quality control of dose and image quality together?
In conventional radiology a well-established connection exists between a detector’s exposure and film brightness. In digital radiology the detector has a much wider dynamic range. Image filtering allows the X-Ray systems to produce similar images under a wide range of exposure conditions. Heavily under-exposed images result in a high level of noise, and reduced anatomical details. Over-exposed images are difficult for an observer to detect. Filtering allows over-exposed images to appear properly exposed. The inability to detect over-exposure could lead to an unjustified increment of the dose.
