Computed Tomography in Pulmonary Tuberculosis

Abstract

CT scans in patients with primary tuberculosis commonly show findings of Iympho-hematogeneous spread of the disease, while those of reactivation tuberculosis commonly show findings of bronchogenic spread. Typical CT findings of primary tuberculosis are airspace consolidation of the middle and lower lobes with mediastinal and hilar lymphadenopathy showing central lower attenuation and peripheral rim en- . hancement. Typical CT findings of reactivation tuberculosis are nodular and linear pulmonary lesions at the apex without lymphadenopathy. High-resolution CT is extremely helpful in understanding the patho-morphologic changes, mode of spread of the disease, sequential morphologic change after antituberculous chemotherapy, and possibly in diagnosing activity of the disease. Centrilobular small nodule or branching linear lesions are the most common findings of fresh active pulmonary tuberculosis, which represent intra- and peri-bronchiolar caseation necrosis. CT is also useful in the evaluation of longstanding destructive pulmonary lesions and tracheobronchial tuberculosis. The importance of the role of CT scan in patients with pulmonary tuberculosis is increasing.