Percutaneous Renal Punction: Requirements And

INTRODUCTION Percutaneous access to kidney is a challenging technique that meets with the difficulty to reach rapidly and accurately an intra-renal target. Today, puncture guidance is performed under fluoroscopic or echographic imaging, each of which presents drawbacks: fluoroscopy provides limited 2D information on localization, whereas echography mostly gives fuzzy images of the target and the puncture trajectory [6]. This paper introduces the principles of computer assisted percutaneous renal puncture (PRP), that would provide the surgeon with an accurate pre-operative 3D planning on CT images and, after a rigid registration with space-localized echographic data, would help him to perform the puncture through an intuitive 2D/3D interface. The whole development stage relied on both CT and US images of a healthy subject. We carried out millimetric registrations on real data, then guidance experiments on a kidney phantom showed encouraging results of 4.7mm between planned and reached targets.