MR Safe Robotic Manipulator for MRI-Guided Intracardiac Catheterization

This paper introduces a robotic manipulator to realize robot-assisted intracardiac catheterization in magnetic resonance imaging (MRI) environment. MRI can offer high-resolution images to visualize soft tissue features such as scars or edema. We hypothesize that robotic catheterization, combined with the enhanced monitoring of lesions creation using MRI intraoperatively, will significantly improve the procedural safety, accuracy, and effectiveness. This is designed particularly for cardiac electrophysiological (EP) intervention, which is an effective treatment of arrhythmia. We present the first MR Safe robot for intracardiac EP intervention. The robot actuation features small hysteresis, effective force transmission, and quick response, which has been experimentally verified for its capability to precisely telemanipulate a standard clinically used EP catheter. We also present timely techniques for real-time positional tracking in MRI and intraoperative image registration, which can be integrated with the presented manipulator to im prove the performance of teleoperated robotic catheterization

An efficient cardiac mapping strategy for radiofrequency catheter ablation with active learning

Objective A major challenge in radiofrequency catheter ablation procedure (RFCA) is the voltage and activation mapping of the endocardium, given a limited mapping time. By learning from expert interventional electrophysiologists (operator), while also making use of an active-learning framework, guidance on performing car- diac voltage mapping can be provided to novice operators, or even directly to catheter robots. Methods A Learning from Demonstration (LfD) framework, based upon previous car- diac mapping procedures performed by an expert operator, in conjunction with Gaus- sian process (GP) model-based active learning, was developed to efficiently perform voltage mapping over right ventricles (RV). The GP model was used to output the next best mapping point, while getting updated towards the underlying voltage data pattern, as more mapping points are taken. A regularized particle filter was used to keep track of the kernel hyperparameter used by GP. The travel cost of the catheter tip was incorporated to produce time-efficient mapping sequences. Results The proposed strategy was validated on a simulated 2D grid mapping task, with leave-one-out experiments on 25 retrospective datasets, in an RV phantom using the Stereotaxis Niobe R © remote magnetic navigation system, and on a tele-operated catheter robot. In comparison to an existing geometry-based method, regression error was reduced, and was minimized at a faster rate over retrospective procedure data. Conclusion A new method of catheter mapping guidance has been proposed based on LfD and active learning. The proposed method provides real-time guidance for the procedure, as well as a live evaluation of mapping sufficiency