Diganostic Radiography Image Evaluation Essay Example | Topics and Well Written Essays - 2250 words

Diganostic Radiography Image Evaluation - Essay Example plate, a good quality image would need to fulfill certain physical criteria for an accurate diagnostic yield, although some parts of it are contributed to by technical soundness of the process of imaging and some are contributed to by the factors essentially related to the patient. Whatever may be the reason, a poor image quality compromises the diagnostic yield, and in some cases, a reading or a diagnosis is not possible, where the radiographic plate needs to be rejected, and re-examination is mandated (Beutel et al., 2000). In this assignment, an evaluatory report of a radiographic image will be presented with a critical discussion about the reasons for it being discarded and a re-examination being recommended. While evaluating an image, it must be borne in mind that evaluation of image is dependent on human vision as related to the examiner. Since radiographic images are essentially black and white, it is to be considered that ideal white light has flat spectrum in which all wavelengths of lights are present. In practice white light sources approximates this property. The light which has no colour or is achromatic such as in radiographic plates has only one descriptor, which is its brightness or grey value. This light has a saturation of 0% and it contains only white light. However, when the saturation varies, it becomes difficult to differentiate between two adjacent differing shades of gray which are considered to be mixtures of varying blacks and whites. Therefore, it is also to be noted that equal distances in physical intensity are not perceived as equal distances in brightness. This occurs due to the fact that intensity levels are dynamic and hence must be measured and indicated log arithmically. Intensity levels must be spaced logarithmically rather than linearly to accomplish equal steps in perceived brightness (Dougeni et al., 2007). The most important parameter of an image is its resolution. The perceived resolution is also determined by the imaging