Free Head Movement Eye Gaze Contingent Ultrasound Interfaces for the da Vinci Surgical System

The current practice of intraoperative ultrasound requires an assistant because the surgeon's hands are occupied with surgical tools or console instruments. This process can be tedious and prone to error. Eye gaze is a promising control modality that can help address this issue. In previous work, a novel feature-based retro-fit eye gaze tracker has been designed for the da Vinci surgical system. In this letter, leveraging the da Vinci research kit, three interfaces incorporate eye gaze, and voice recognition into the da Vinci surgical system for ultrasound control in one common framework. This letter aims to improve autonomous use of ultrasound for surgeons. Since eye gaze tracking is sensitive to head movement, a novel calibration procedure is also proposed to accommodate head motion by decomposing pupil movement into eye rotation and head motion. This ensures that the eye gaze tracking can be reliably used as a control modality. A user study (N = 20) has shown that the designed eye gaze tracker has a mean binocular accuracy of 1.98° with mean -0.92 mm horizontal and 16.83-mm vertical head movement. A preliminary user study (N = 9) has shown that eye gaze tracking for ultrasound control has the potential to improve the way surgeons interact with their instrumentation and increase surgical autonomy.