Purpose: Previous studies have shown the ability of rubidium-82 (82Rb) positron emission tomography (PET) imaging to quantitatively measure myocardial blood flow (MBF), many of which are performed using two-dimensional (2D) imaging. Three-dimensional (3D) imaging provides increased sensitivity and may result in decreased costs owing to a reduction in the required injected activity of radiotracer. This study compares 2D and 3D 82Rb PET MBF results obtained in the same imaging session.
Methods: Three-dimensional and 2D 82Rb perfusion imaging was performed in canines on a GE Discovery LS PET/CT scanner at rest and during hyperemia in stunned and infarcted tissue. MBF (ml/min/g) was determined using a 1-compartment model and an extraction correction of the uptake rate and analyzed using a standard 17-segment model.
Results: A strong, significant correlation was present (ρ = 0.95, P<0.0001). Average 3D MBF values were slightly lower at rest and higher during stress versus 2D. MBF results in normal, stunned, and infarcted tissue differed by 7% on average and significant increases in MBF from rest to hyperemia were noted with both the techniques.
Conclusion: These results imply that MBF results obtained in 3D are comparable with traditional 2D imaging. Therefore, it may be possible to use 3D imaging with lower administered activity, helping to reduce costs and patient dose without compromising quantitative information.
aLawson Health Research Institute and Nuclear Medicine Department, St. Joseph's Health Care
bDivision of Cardiology, London Health Sciences Centre, London
cNational Cardiac PET Centre, University of Ottawa Heart Institute, Ottawa, Ontario, Canada
Correspondence to Dr Frank S. Prato, Lawson Health Research Institute and Nuclear Medicine Department, 268 Grosvenor Street, St. Joseph's Health Care, London, ON N6A 4V2, Canada
Tel: +1 519 646 6000 x64140; fax: +1 519 646 6399;
Received 24 February 2009 Revised 5 June 2009 Accepted 30 August 2009