Introduction:99mTc-methoxy-isobutyl-isonitrile myocardial perfusion imaging (99mTc-MIBI MPI), is the most commonly used noninvasive stress imaging method for the diagnosis of coronary artery disease (CAD) (J1). However, despite its overall effectiveness, the interpretation of MPI is complex due to potential imaging artifacts, including those related to the patient and equipment (J). Soft tissue attenuation, such as that caused by breast position or the diaphragm, is one of the most common factors that can reduce the test accuracy for detecting CAD and affect image quality. (G4). To reduce the factors that decrease quality, methods such as electrocardiography-gated imaging, attenuation correction software, and changing the patient’s position have been proposed (G4, G5). MPI is conventionally performed in the supine position (Y). However, different positions are now being used to achieve better imaging quality (G).One approach that has been reported to improve the diagnostic accuracy of MPI is the use of a supine-prone combination rather than supine MPI alone (C).In recent years, numerous studies have shown significant reductions in both diagnostic performance and patient radiation exposure when using ”stress-first” imaging, such that a normal stress study can eliminate the need for subsequent rest imaging (A31, A32, A33, A34). The normal stress study will eliminate the need for subsequent rest imaging, thereby reducing the examination time, radiation dose, and the doses of radiopharmaceuticals used.In cases of diaphragmatic or breast attenuation, the absence of perfusion defects in stress-prone imaging can help exclude ischemic heart disease, especially when combined with a supine study, thereby reducing the need for rest imaging (O).It has been reported that the addition of prone MPI to supine MPI increases the diagnostic accuracy in populations consisting of both women and men (C6, C7, C8). However, data directly comparing these two imaging strategies, especially in cohorts consisting solely of men, are limited (C).Despite its potential to increase diagnostic accuracy, the combined supine-prone MPI is not widely utilized.In our study, we retrospectively investigated the effect of stress supine-only, stress prone-only, and combined stress supine-prone MPS studies on the need for rest imaging in male patients without known coronary artery disease in whom there is limited data in the literature.