In recent years, analysis of myocardial ischemia using computed tomography (CT) has developed from visual analysis of myocardial perfusion defects to a technique with the ability to quantify myocardial perfusion. In this thesis, an ex vivo porcine heart model, optimized for use in a CT environment, was used to validate quantitative CT myocardial perfusion analysis. The porcine heart model provides direct control over physiological parameters and a stenosis in one of the coronary arteries can be induced. Quantitative measurements of myocardial blood flow, based on CT imaging, showed close correlation with stepwise reduction of fractional flow reserve in the stenotic coronary artery. Still, CT perfusion measurements showed an underestimation of the absolute myocardial blood flow in the model. In this thesis we showed that a possible cause of the underestimation is the limited temporal sampling. This should be increased for more accurate CT perfusion measurements. Dual energy CT is another technique that could be used to provide a semi-quantitative measure for myocardial perfusion. The ability to acquire iodine concentration measurements was tested in two high-end systems. Both showed accurate results for the measurement of multiple iodine concentrations. Still, dual energy CT is a single-shot technique. Therefore, scan triggering should be optimal, within an 8 second window of optimal contrast enhancement. The results of the experiments described in this thesis indicate that quantification of myocardial perfusion in CT has additional value beyond visual analysis to detect hemodynamically significant coronary artery disease.
|Qualification||Doctor of Philosophy|
|Place of Publication||[Groningen]|
|Publication status||Published - 2017|