Validation of regional myocardial blood flow quantification using three-dimensional PET with rubidium-82: repeatability and comparison with two-dimensional PET data acquisition.

Introduction Three-dimensional (3D) data acquisition is now standard on PET/computed tomography scanners. The aim of this study was to evaluate the repeatability of myocardial blood flow (MBF) estimation with rubidium-82 (Rb-82) 3D PET and to validate regional MBF measurements by comparison with two-dimensional (2D) PET. Patients and methods Fifteen healthy individuals (31.6 +/- 11.4 years old) were enrolled for the evaluation of the short-term repeatability of rest 3D MBF quantification. Another 19 healthy individuals (35.3 +/- 12.6 years old) underwent rest and pharmacological stress PET using 2D and 3D data acquisition within a 1-month interval. The injected dose was 1500 MBq for 2D and 555 MBq for 3D PET acquisition. Results MBF at rest showed good repeatability [whole left ventricular MBF; 0.54 +/- 0.13 vs. 0.52 +/- 0.13 mL/min/g,P = 0.98]. Rest MBF, stress MBF, and myocardial flow reserve (MFR) were not significantly different between 3D and 2D data acquisition. 3D MBF correlated well with 2D MBF over a wide flow range for both whole left ventricular (r = 0.97,P < 0.0001) and regional values (r = 0.61,P < 0.0001). Conclusion MBF measured with 3D PET showed very good test-retest repeatability. Whole left ventricular and regional MBF measurements obtained using lower(82)Rb-dose 3D PET were highly correlated over a wide range with those from 2D PET. Therefore, MBF with 3D PET can be applied using a lower(82)Rb dosage in clinical settings with reduced radiation exposure.