Usefulness of Perfusion CT in Progressive Massive Fibrosis

ABSTRACT

PURPOSE: We wanted to evaluate the usefulness of perfusion CT for the diagnosis of progressive massive fibrosis. MATERIALS AND METHODS: We retrospectively analyzed the perfusion CT images of 20 lesions that showed progressive massive fibrosis in 13 patients. Using 16 channel multi-detector CT, a dynamic study was performed with the multiple spiral acquisition technique at 0 (precontrast), 15, 30, 45, 60, 90, 120, 180, and 300 seconds after contrast injection. The perfusion image was reformatted using these source images; it was scored on the volume map and washout map by visual inspection and then compared with 20 lesions of lung cancer. RESULTS: The volume map showed either middle or low perfusion for 19 among the 20 lesions. The washout map also showed a weak or moderate washout pattern. The kappa values (>0.818) for the inter-reader agreement reached statistical significance (p<0.01). High perfusion on the volume map was seen in 1 case (5%) in the PMF group and in 19 cases (95%) in the lung cancer group. Intense washout on the washout map was seen in 1 case (5%) in the PMF group and in 14 cases (70%) in the lung cancer group. There was a significant difference between the two groups (x2=32.129, p<0.01). CONCLUSION: Perfusion CT consisting of the volume map and washout map can be a useful method for the differential diagnosis between PMF and lung cancer.