Abstract: Objective To analyse the computed assisted tomographic (CT) manifestations of pulmonary tuberculosis (TB) in old people and the usefulness of CT scan in the diagnosis of pulmonary TB.Methods From August 1993 to March 2000 160 aged patients (age range: 65 89 years; mean age 72.5 years) with pulmonary TB underwent chest CT scan. High resolution CT (HRCT) were done in 112 patients. 84 patients were performed contrast enhanced CT scan. Results The characteristics of the chest CT scan in this series included: (1) The lesions were distributed in more than one lobe in 78.6% of the patients. Both the upper and lower lobe were involved in 56.4%, upper lobes were involved in 20.5%, and only involvement of the lower lobes in 23.0%. (2)Fibrosis as the predominantly manifestation was seen in 89.4%. The presentations of cavity,calcification,pleural thickness,tuberculoma were seen in 48.5%, 40.8%, 18.4%, and 6.8%, respectively. (3)Contrast enhancement CT showed that lesions were markedly enhanced in 90.5% (76/84). (4) The findings of the active lesions were presented in 76.8%, which manifested as 2～4mm centrilobular nodules and branching linear opacities,or 5～8 mm fuzzy nodules associated with thickening of the interlobular septa and the bronchial wall. (5) Pulmonary TB associated with lung cancer was seen in 9.4% (15/160) of the patients.Conclusion The characteristics of pulnonary TB in aged people included predominant fibrosis,preferring to involvement of the lower lobes, and marked lesion enhancement. The incidence of TB associated with lung cancer is relatively high. HRCT is useful for determinated the activity of pulmonary TB.

Key words: Tuberculosi,pulmonary, Tomography,X ray computed