To evaluate the clinical value of the multi-detector row computed tomography (MDCT) in the quantitative assessment of lung volumes and to assess the relationship between the MDCT results and disease severity as determined by a pulmonary function test (PFT) in Chronic Obstructive Pulmonary Disease (COPD) patients.

We performed a PFT and MDCT on 39 COPD patients. Using the GOLD classification, we divided the patients into three groups according to disease severity; stage I (mild, n=10), stage II (moderate, n=15), and stage III (severe, n=14). Using the pulmo-CT software program, we measured the proportion of lung volumes with attenuation values below -910 and -950 HU.

The mean FEV1 (% of predicted) and FEV1/FVC was 82.2±2% and 66.2±3% in stage I, 53.5±11% and 52±6% in stage II, and 32.3±7% and 44.2±13% in stage III, respectively. Differences in lung volume percentages at each of the thresholds (-910 and -950 HU) among the 3 stages were statistically significant (p <0.01, p <0.01) and correlated well with the FEV1 and FEV1/FVC (r=-0.803, r=-0.766, r=-0.817, and r=-0.795, respectively).

The volumetric measurement obtained by MDCT provides an accurate means of quantifying pulmonary emphysema.