[67Ga scanning in sarcoidosis]

The value of 67Ga scans in selected cases of sarcoidosis was studied at various stages in order to assess its value as a supplement to clinical, radiological and perfusion studies. During stages I and II, radioactive gallium is taken up by the granulomatous nodes in the hilum and mediastinum and in the interstitial focal pulmonary infiltrates. After complete regression of the hilar and mediastinal lymphadenopathy or of the pulmonary infiltrates, radio-active uptake can no longer be demonstrated. Gallium scans are valuable in showing whether there is active granulomatous infiltration into the lungs when there is known scarring resulting in abnormal perfusion conditions. The gallium scan may indicate that further treatment is desirable. A comparison of serial radiographs and the 67Ga scan provides an indication of the activity of the granulomatous disease; a comparison of the radiological findings and of perfusion scans shows the severity of perfusion abnormalities caused by fibrosis. The investigation has shown that the granulomatous lesions persit even though radiological, clinical and functional investigations have indicated the presence of fibrotic scarring. Radiography, perfusion and gallium scans provide an understanding of the dynamics of this disease.