Closed-Loop Magnetic Manipulation for Robotic Transesophageal Echocardiography

TL;DR

This paper introduces a magnetic control framework for robotic transesophageal echocardiography that enables precise, intuitive, and real-time probe manipulation using a modified standard TEE probe with magnetic and inertial sensors.

Contribution

The work presents a novel magnetic manipulation method for TEE probes that simplifies control and enhances accuracy without complex actuator structures.

Findings

Achieved 6-DOF localization and 5-DOF closed-loop control.

Validated effectiveness through extensive experiments and phantom testing.

Demonstrated applicability for tele-operated TEE in realistic conditions.

Abstract

This paper presents a closed-loop magnetic manipulation framework for robotic transesophageal echocardiography (TEE) acquisitions. Different from previous work on intracorporeal robotic ultrasound acquisitions that focus on continuum robot control, we first investigate the use of magnetic control methods for more direct, intuitive, and accurate manipulation of the distal tip of the probe. We modify a standard TEE probe by attaching a permanent magnet and an inertial measurement unit sensor to the probe tip and replacing the flexible gastroscope with a soft tether containing only wires for transmitting ultrasound signals, and show that 6-DOF localization and 5-DOF closed-loop control of the probe can be achieved with an external permanent magnet based on the fusion of internal inertial measurement and external magnetic field sensing data. The proposed method does not require complex structures or motions of the actuator and the probe compared with existing magnetic manipulation methods. We have conducted extensive experiments to validate the effectiveness of the framework in terms of localization accuracy, update rate, workspace size, and tracking accuracy. In addition, our results obtained on a realistic cardiac tissue-mimicking phantom show that the proposed framework is applicable in real conditions and can generally meet the requirements for tele-operated TEE acquisitions.