Author/Authors :
Darkhor, Parvaneh Immunology Research Center - Tabriz University of Medical Sciences, Tabriz, Iran , Mahmoudian, Babak Departments of Radiology - Tabriz University of Medical Sciences, Tabriz, Iran , Gharepapagh, Esmaeil Departments of Radiology - Tabriz University of Medical Sciences, Tabriz, Iran , Zakavi, Rasoul Nuclear Medicine Research Center - Mashhad University of Medical Sciences, Mashhad, Iran , Pirayesh Islamian, Jalil Departments of Medical Physics - Tabriz University of Medical Sciences, Tabriz, Iran
Abstract :
Introduction: Myocardial perfusion SPECT by 99mTc-Sestamibi and 99mTc-Tetrofosmin radiopharmaceuticals usually
presents a false significant increase in the radiotracer uptake in the inferior myocardium due to the uptake in organs such as
liver, bowel, stomach and biliary system. The present study evaluated a suitable Slit angle for differentiating extra-cardiac
activities by Slit Slat collimation.
Methods: The Siemens E.CAM gamma camera equipped with a Low Energy High Resolution (LEHR) collimator was
simulated with the Simulating Medical Imaging Nuclear Detectors (SIMIND)Monte Carlo program. Following the verification
of the simulation, a Slit Slat collimator was simulated for SPECT imaging of a NURBS-based Cardiac Torso (NCAT) phantom
with different Slit angels ranged from 0 to 30 degrees. The reconstructed images were qualitatively assessed with blinded
observer method by three nuclear medicine specialists.
Results: The improved differentiation of the bowel activity from the cardiac was obtained by a Slit-Slat collimator with the
Slit angle of 7 degree. While for gastric activity differentiation an angle of 15 degree for the Slit was useful.
Conclusion: The results showed that Slit Slat collimation with 7 and 15 Slit angle provide a suitable differentiation of the
bowel and gastric activities from the cardia, respectively.
Keywords :
Myocardium , NCAT , SPECT , Slit Slat collimator , SIMIND Monte Carlo
