Closed-loop Control of Steerable Balloon Endoscopes for Robot-assisted Transcatheter Intracardiac Procedures

TL;DR

This paper introduces a steerable balloon cardioscope with closed-loop control for precise intracardiac visualization and tool navigation, enhancing minimally invasive heart procedures.

Contribution

It presents a novel balloon-based cardioscope design with independent control of diameter and bending angle, including an image-based closed-loop control system for stable orientation.

Findings

Successful demonstration of balloon inflation control for independent diameter and bending angle.

Implementation of image-based closed-loop control for stable orientation during procedures.

Potential adaptability of balloon design for various intracardiac tasks.

Abstract

To move away from open-heart surgery towards safer transcatheter procedures, there is a growing need for improved imaging techniques and robotic solutions to enable simple, accurate tool navigation. Common imaging modalities, such as fluoroscopy and ultrasound, have limitations that can be overcome using cardioscopy, i.e., direct optical visualization inside the beating heart. We present a cardioscope designed as a steerable balloon. As a balloon, it can be collapsed to pass through the vasculature and subsequently inflated inside the heart for visualization and tool delivery through an integrated working channel. Through careful design of balloon wall thickness, a single input, balloon inflation pressure, is used to independently control two outputs, balloon diameter (corresponding to field of view diameter) and balloon bending angle (enabling precise working channel positioning). This balloon technology can be tuned to produce cardioscopes designed for a range of intracardiac tasks. To illustrate this approach, a balloon design is presented for the specific task of aortic leaflet laceration. Image-based closed-loop control of bending angle is also demonstrated as a means of enabling stable orientation control during tool insertion and removal.