Computer-assisted aided endovascular navigation: Study of geometrical transformations

Abstract

Nowadays, more and more minimally invasive vascular interventions require the exact location and orientation of the endovascular tools (i.e., balloon, stent) with respect to the patient in a surgical environment. The implementation of a navigation guidance system able to make this procedure safer and more precise, begin with an image registration between digital subtracted angiography images and a preoperative volume image. In this work, an experimental approach is proposed, consisting in a framework based on the cooperation between the real environment (RE) where the intervention takes place and a patient-specific virtual environment (VE), which contains a virtual operation room including a C-arm model as well as the 3D preoperative patient data. Special attention on the geometrical transformations is considered at the 3D/2D matching stage in order to achieve the 3D tracking of endovascular tools and the simultaneous visualization of related 2D intra- and 3D pre-operative information. With the aim of exploiting the whole available information at the different observation stages through a cooperative approach, this paper focuses on the definition for the different geometrical transformations implied in the 2D/3D matching, as well as on the estimation of the transformation parameters based on the used and combination of different types of data and methods (Calibration, 3D tracking, image registration). © Springer-Verlag Berlin Heidelberg 2007.