Elastic registration for stent enhancement in X-ray image sequences

Curing coronary artery disease typically involves deploying a stent (a fine mesh of wire) supported by a balloon inside the patient artery. This procedure is monitored by X-ray fluoroscopy where stent visibility is challenging. Since 2000, stent enhancement techniques for X-ray fluoroscopy image sequences have become popular. They are based on motion compensated temporal integration of the stent images. The motion of the stent is classically inferred from the motion of the highly contrasted balloon marker balls. We propose a technique that compensates the motion of the whole guide-wire in the neighborhood of the marker balls. We demonstrate that the guide wire-based registration enables better enhanced images in 28% of the cases whereas marker ball based registration is better only in 4% of the cases. We provide examples, qualitative and quantitative analysis on a database of 144 clinical cases.