Because of the power of HRCT to detect the minute changes in lung parenchyme and the advantage of noninvasiveness, it may be the ideal method of follow-up evaluation of the patients with diffuse interstitial pulmonary fibrosis. So the aim of the study is to find out whether the change of HRCT during the course of the disease can represent the change in symptom and pulmonary function rest.

Thirteen patients with diagnosis of diffuse interstitial pulmonary fibrosis who had more than two times of HRCT during the course of disease were studied. The extent of the disease in HRCT was measured at three levels using image analyzer The ralationship between the percent change in the disease extent in HRCT, symptom score, and pulmonary function testis were analysed.

The change of disease extent in HRCT has good correlation with the change in dyspnea and diffusion capacity(r=0.716, p=0.0012). But there was no correlation between the change of HRCT and FVC or TLC. Also significant inverse correlation was noted between the change in dyspnea and diffusion capacity(r=-0.707, p=0.0047).

These data suggest that HRCT may be a good method of follow-up in diffuse interstitial pulmonary fibrosis.