Registration of high-resolution 3D atrial images with electroanatomical cardiac mapping: evaluation of registration methodology

Abstract

Registration of atrial high-resolution CT and MR images with a cardiac mapping system can provide real-time electrical activation information, catheter tracking, and recording of lesion position. The cardiac mapping and navigation system comprises a miniature passive magnetic field sensor, an external ultralow magnetic field emitter (location pad), and a processing unit (CARTO, BiosenseWebster). We developed a progressive methodology for both interactively and automatically registering high-resolution 3D atrial images (MR or CT) with the corresponding electrophysiological (EP) points of 3D electro-anatomical (EA) maps. This methodology consists of four types of registration algorithms ranging from landmark-based to surface-based registration. We evaluated the methodology through phantom and patient studies. In the phantom study, we obtain a CT scan of a transparent heart phantom, and then use the CARTO system to visually pick a number of points inside the transparent phantom. After segmenting the atrium into a 3D surface, we register it to the measured EA map. The results are compared to the manual EA point measurements. In the 13-patient study, the four types of registrations are evaluated: visual alignment, landmark registration (three EA points are used), surface-based registration (all EA points are used), and local surface-based registration (a subset of the EA points is used, and one specific point is given a higher weight for a better "local registration"). Surface-based registration proves to be clearly superior to visual alignment. This new registration methodology may help in creating a novel and more visually interactive workflow for EP procedures, with more accurate EA map acquisitions. This may improve the ablation accuracy in atrial fibrillation (AFib) procedures, decrease the dependency on fluoroscopy, and also lead to less radiation delivered to the patient.

Visualization in Image-Guided Interventions

“…Advances in the procedure include incorporation of detailed, patient-specific anatomical image data [Dickfeld et al 2003;Reddy et al 2004;Sra et al 2005;Sun et al 2005] where a model is built from preoperative CT or MR data. These models are then registered into the space of the patient during the procedure using landmark-matching and surface-based approaches.…”

A combined surface and volumetric approach for registration of patient specific models into left atrial cardiac ablation procedures

“…While standard visualization tools are important for guidance, there has recently been increased interest in incorporating detailed, patient-specific models into the procedure [2,3,4,5,6,7,8,9,10]. High resolution computed-tomography (CT) or magnetic resonance scans are taken preoperatively and incorporated into the procedure by registering the realworld patient space with the image space.…”

A piecewise patch-to-model matching method for image-guided cardiac catheter ablation

“…The 3D map, called an electro-anatomical map (EAM), is generated from 60 to 120 sampled points. Because the EAM is a low-resolution representation of the LA, several approaches have been developed to integrate a high-resolution pre-operative model of the LA [13–29]. Unfortunately, after the creation of the EAM and registration to the high-resolution model, the cardiologist will often return to x-ray fluoroscopy and/or intra-cardiac echocardiography for guidance because both provide real-time feedback of the anatomy and ablation catheter.…”