FDG PET/CT for Sarcoidosis

Recently, remarkable progress in cardiac imaging with FDG PET and MRI has been made. FDG PET detects active inflammatory lesions in cardiac sarcoidosis (CS) as hot spots with a better sensitivity than 67Ga scintigraphy. The new guidelines for diagnosis and treatment of CS were published by the Heart Rhythm Society in 2014, and more recently revised by the Japanese Circulation Society in 2017. In the past few years, many studies have demonstrated the diagnostic utility of FDG PET in patients with CS; therefore, abnormally high FDG accumulation in the heart was adopted as the major criteria for cardiac involvement of sarcoidosis. At present, FDG PET/CT is considered mandatory in the clinical diagnosis group of the updated guidelines.