Towards patient specific catheter selection: Computation of aortic geometry based on fused MRI data

In coronary angiography, a catheter's tip has to be directed through the aorta towards the ostium - the region where the coronary arteries arise. Due to the anatomical variation in different humans, there is no common catheter which can be used for all patients. Thus, in a trial and error procedure cardiologists find a catheter that fits to the patient's anatomy. To replace this time consuming approach by providing a computer aided planning tool to be used prior to the intervention is the focus of our work. First of all, it is necessary for such a system to derive geometrical parameters for the patient's aorta as well as for the different available catheters. Based thereon, the best fitting catheter can be selected. In this paper, we discuss the first step: the computation of geometrical parameters from the patient's image data. Due to the setting defined by our clinical partner, two MRI data sets are acquired and should be used for the computation. This requires a specific image processing pipeline which we present here and which has to our knowledge not been proposed so far. Furthermore, we show first results obtained for real clinical data sets and discuss the subsequent steps for the development of the catheter selection tool.