COMPUTED TOMOGRAPHIC EVALUATION OF PULMONARY TUBERCULOSIS AND ITS SEQUELAE

INTRODUCTION: Tuberculosis is a specific granulomatous disease, caused by mycobacterium tuberculosis. CT scan, particularly HRCT seems to be most useful imaging modality for tuberculous infection and its sequelae. CT is much more sensitive in identifying complications of tuberculosis than any other imaging modality. MATERIALS & METHODS: A total of ninety cases of pulmonary tuberculosis were included in the present study. A detailed history, clinical examination and routine laboratory examinations of all the cases were carried out for the confirmation of tuberculosis. All the cases had chest radiography postero-anterior view in erect position using 1000 mA digital X-ray machine of Shimadzu. In all the cases CT examination were performed using Siemens Somatom ARSP - a third generation spiral scanner, within a week of starting antituberculous therapy. OBSERVATION: The CT findings were divided into four groups, based on predominant pattern of involvement. These groups are-predominant parenchymal excluding military (57 cases), predominant miliary parenchymal (15 cases), plural effusion (9 cases), and mediastinal lymphadenopathy (9 cases). The predominant parenchymal lesions further consisted of three major patterns. These are nodular opacities (57 cases), confluent consolidation (21 cases) and consolidation with associated loss of volume (36 cases). CONCLUSION: CT showed three major patterns of parenchymal lesions. The nodular opacity pattern suggesting bronchogenic spread. Cavitations were most common with consolidation with associated loss of volume, lesions suggesting liquifactive necrosis of caseous focus.