Image registration

Abstract

In cardiac roadmapping, a 'roadmap', which is typically a representation of the vasculature of a patient obtained via previously acquired data from a CT scan, is overlaid on live intervention data, showing the position of an intervention device obtained using fluoroscopy. In this way, the intervention device may be tracked inside a realistic representation of the patient. The accurate registration of the fluoroscopic image to the roadmap data is an important step, otherwise the reported live position of the intervention device would not be shown at an accurate position inside the roadmap. Registration can be performed by the injection of contrast medium. In the case of cardiac roadmapping, the small vessel diameters mean that it is possible to register intervention devices directly. However, the behavior of intervention devices in larger vessels is difficult to predict, and so device-based registration is harder to achieve in such a context. By detecting the presence of a specific intervention device and a specific vascular context, an accurate registration of the intervention device to the 3D roadmap can be provided via comparison to a library of known device configurations.