[Diagnostic imagings of mediastinal mass].

Conventional postero anterior and lateral chest radiographs constitute the first examination of the mediastinum. A well-penetrating radiograph of 130KV or more is needed to optimally, demonstrate the lung-mediastinal borders as well as air-containing structures in the central thorax. Many mediastinal lesions that are obscure on conventional films are clearly demonstrated by CT, which clearly separates structures in the axial plane. The extent and localization of tumor can be more easily determined by CT than by other techniques. Conventional chest tomography has been popular in the past, but with the advent of CT scanning, this procedure has little in evaluating a mediastinal mass if CT is available. Nuclear scan using gallium 67 is fairly accurate in identifying inflammatory lesions and malignant tumors, but with the advent of CT such studies have little if any use in the mediastinum. The list of CT indications conforms somewhat to the report published by the Society of Computed Body Tomography, with some modifications. CT examination of the mediastinum has become one of the most useful complementary modalities in the diagnostic field and often not only is it complementary, but it may be an alternative to other X-ray studies, isotope scanning, or mediastinoscopy.