Most of the tuberculosis can be seen on CT when it is well. Tuberculosis is an infectious disease and an infectious disease. It occurs mostly in the upper lungs or the dorsal segment of the lower lobe, and appears mainly as exudative lesions on CT, such as patchy, punctate or cloudy shadows in both upper lungs, with a dense central focus of the lesion and relatively thin margins. In the case of primary TB, there may also be hilar or mediastinal lymph node enlargement, or in some cases, proliferative disease with a nodular appearance, and in some cases, marked cavitation. In the case of cornual tuberculosis, it mostly manifests as cornual foci of relatively uniform size, density, and distribution in both upper lungs. After treatment of tuberculosis, these manifested lesions on CT of the lungs will gradually fibrosis, or form calcified foci, and the cavities in the lungs will close. Therefore, these dynamic changes on CT are used to initially determine whether the TB is cured.