Abstract: Objective To study the change of pulmonary tuberculosis(TB) CT image in the active and post-treatment phases.Methods Thirty-one active TB patients were selcted to do spiral CT scan to observe the change of the image before and after treatment. Results It showed that check-out rate of active images was 100.0% before treatment and 35.5% after treatment.The most higher check-out rate of active image was ground-glass opacity(87.1%),followed by centrilobular nodules with segmental distribution(80.6%),lobular consolidation(80.1),tree in bud(61.3%),thickening of the bronchial walls(58.1%),thick-wall cavity(48.4%),segmental or lobar consolidation(32.3%) at the start of the treatment.While after completion of the treatment,the check-out rate of those image changed to 0,19.4%,0,0,12.9%,0,3.2% respectively.Many kinds of active CT image which can be found before treatment were reduced and mainly showed one single image in one patient after the treatment.The difference was significant(P<0.01). Conclusion CT was helpful to judge treatment effect of active TB with high sensitivity but low specificity.

Key words: Pulmonary tuberculosis/diagnosis, X-ray computer,tomography