CT findings of pulmonary artery aneurysms during treatment for Behçet's disease

The purpose of this study was to evaluate the CT findings of pulmonary artery aneurysms in patients being treated for Behçet's disease.Thirteen patients with Behçet's disease who had a total of 46 aneurysms were included in the study. All patients underwent helical CT before and after treatment. Both initial and follow-up CT scans were evaluated for location, number, and size of aneurysms and for thrombosis and pulmonary parenchyma changes.Thirty-five (76%) of the 46 aneurysms completely disappeared during the 3-42 months of treatment (mean, 21 months), and the remaining 11 aneurysms (24%) became smaller. Both disappearance and regression of aneurysms were preceded by thrombus formation. In 15 initially thrombosed aneurysms (33%), the thrombus increased in size during treatment. After treatment, the thrombus regressed and the pulmonary artery aneurysms disappeared. Thirty-one initially nonthrombosed aneurysms (67%) first became thrombosed during treatment; later, the thrombus regressed and the aneurysm decreased in size. Perianeurysmal consolidation and air-space nodules detected in seven patients disappeared in the early stages of treatment. Mosaic attenuation areas were seen in eight patients and disappeared in seven (88%) after treatment.Pulmonary artery aneurysms in Behçet's disease may become smaller or disappear with medical treatment. Mural thrombotic changes may be observed during the regression of pulmonary artery aneurysms. Helical CT is helpful in the diagnosis and follow-up of aneurysms and thrombosis in Behçet's disease.