The CT findings of pulmonary sarcoidosis: analysis of 25 patients.

We analyzed the CT findings in 25 patients with biopsy-proved pulmonary sarcoidosis. In all 25 patients, 10-mm collimation scans were available. In 16 of the 25 patients, select 1.5-mm scans were obtained. These were retrospectively targeted by using a 20- to 25-cm field of view and a high-spatial-resolution algorithm. The CT and pathologic findings were compared in two patients in whom surgical specimens of the lung were available. CT findings included hilar and mediastinal adenopathy (n = 22), subpleural nodules (n = 19), and 1- to 10-mm-diameter nodules (n = 17) and irregular linear densities (n = 12), both mainly along the bronchovascular structures. High-resolution CT was superior to conventional CT in the assessment of subpleural nodules and irregular linear densities, but conventional CT was superior in the assessment of peribronchovascular nodules. The two gross pathologic specimens showed the sarcoid granulomas to be mostly along the lymphatics in the peribronchovascular sheath and, to a lesser extent, in subpleural and interlobar septal lymphatics. We conclude that the characteristic CT appearance of pulmonary sarcoidosis consists of small nodules and irregular linear densities along the bronchovascular bundles.