7th Dutch Bio-Medical Engineering Conference

tag

11:15
15 mins

Myocardial Perfusion Phantom Experiments in CT
Marije E. Kamphuis, Gijs J. de Vries, Marcel J.W. Greuter, Riemer H.J.A. Slart, Cornelis H. Slump

Session: The heart
Session starts: Thursday 24 January, 10:30
Presentation starts: 11:15
Room: Lecture room 559

Marije E. Kamphuis (Technical Medical Centre)
Gijs J. de Vries ()
Marcel J.W. Greuter ()
Riemer H.J.A. Slart ()
Cornelis H. Slump ()

Abstract:
Myocardial perfusion imaging (MPI) is a common test method to diagnose obstructive coronary artery disease. Institutional variations like imaging modalities, vendors and protocols limit widespread implementation of a validated standard in MPI. In line with proper clinical decision-making, absolute quantification of myocardial blood flow (MBF) can facilitate validation and standardization. This research focuses on the development of a multimodal myocardial perfusion phantom, which we first tested in CT. The prototype perfusion phantom comprises a cylindrical tube simulating the aorta (Ø=3 cm) and a dialysis filter (Fresenius) simulating the myocardium. Both are incorporated in an anthropomorphic thorax phantom (QRM GmbH). The simulated aorta and myocardium are built in separate open flow circuits to individually assess sensitivity to flow and contrast protocol variations. Each flow circuit has a gear pump that generates continuous aortic flow (3-6 Lmin-1) or myocardial flow (100-750 mLmin-1), respectively. Experiments were performed in contrast enhanced dynamic first-pass CT (SOMATOM, Force, Siemens). MPI was validated by comparing computed MBF from Perfusion CT software and measured flow (FCH-mini POM Flowmeter, Biotech) as reference. The MBF was computed according to the upslope method, whereby dividing the maximum slope of the myocardial time intensity curve (TIC) by the maximum intensity of the arterial input function (AIF). Most of the requirements for the myocardial perfusion phantom, flow circuit and MBF quantification method were met. The obtained TICs from the phantom were compared to the TIC of healthy patients. Similar contrast enhancement was observed for the AIF, though the upslope myocardial perfusion rate was higher in the phantom setup compared to the in vivo situation. The computed and measured MBF showed a good correlation. We have developed a novel, multimodal and multivendor myocardial perfusion phantom using measured sensor flow as reference. Initial results showed a good correlation between computed and measured MBF on CT.