Myocardial Perfusion Imaging (mpi); Superior Clinical Performance, a Comparison between Filtered Back- Projection (fbp) and Astonish Iterative Reconstruction Method with Cardiac Catheterization

.. Objective: Myocardial perfusion imaging (MPI) with superior quality of images in least acquisition time is imperative for diagnostic purpose. The objective of this study was to compare the Filter Back Projection (FBP) and half time Astonish reconstruction techniques in diagnosis of coronary artery disease using cardiac catheterization as gold standard. Place and period of study: Study was conducted in nuclear cardiology department, at Faisalabad institute of cardiology, Faisalabad from November 2014 to July2015. Material & Methods: A total of 60patients (56 + 19years) underwent gated MPI with Tc-99m Sestamibi and 30 patients of these underwent cardiac catheterization as well. Images were reconstructed with half time Astonish and FBP algorithms. CAD detection, LVEF, perfusion defect comparison using polar maps and diagnostic performance were calculated. Results: Perfusion defects calculated through Astonish and FBP techniques were compared and correlated with coronary angiogram. The sensitivity, specificity and accuracy for detection of CAD in vascular territories (LAD, LCX & RCA) of the patients were 72%, 41% and 57% with FBP and 86%, 54% and 71% with Astonish. The calculated LVEF showed good correlation (r = 0.8773) between Astonish and cardiac catheterization. Conclusion: There were no significant changes in image quality of Half-time Astonish compared to full-time FBP. Astonish reconstruction showed equal resolution, reduced background noise and radiation dose. Reduced scanning time will improve patient scan quality due to less chance of attenuation.