Superimposed single-photon emission computed tomography and X-ray computed tomography of the heart: Methodical aspects
Global radiology and nuclear medicine have recently shown a clear trend towards hybrid (combined, superimposed) studies. Unfortunately, the Russian literature virtually lacks both method­ological and research works on this topic. The basis for this paper was the guidelines of the North American Society of Nuclear Medicine and Molecular Imaging, the North American Society of Nuclear Cardiology, and the Society of Cardiovascular Computed Tomography and the principles as jointly set out by the European Society of Nuclear Medicine, the European Society of Radiology, and the European Association of Nuclear Medicine. The purpose of the paper is to familiarize readers with some methodical aspects of performing superimposed single-photon emission computed tomography (SPECT) and X-ray computed tomography (CT) of the heart. This publication discusses the main indications for and contraindications to hybrid cardiological studies and gives other data that are useful to select patients for examination. A patient's preparation and prevention measures are described. There is information on major radiotracers and equipment for superimposed studies. There are imaging parame­ters and information on the correction of gamma-ray quantum absorption according to CT data. The paper concerns the inter­pretation of the results of identifying coronary artery calcification and those of CT coronarography and myocardial perfusion scintigraphy. It presents the methodical aspects of superimposi-tion of radionuclide and CT images, the possible sources of errors during superimposed SPECT/CT, and recommendations for mak­ing a diagnostic conclusion. The issues of radiation load and radi­ation safety are discussed.