Pioneering semi-rigid stability: navigating the female pelvis for enhanced precision in binocular vision guidance

Purpose To overcome the surface marker drift issue in semi-rigid pelvic structures and establish a foundation for the binocular vision navigation targeting semi-rigid anatomical structures within the human body. Methods The study was conducted at Chongqing health center for women and children form April to June 2024. Surface markers were placed on 20 volunteers with semi-rigid pelvic anatomy. Respiratory and movement-induced displacement data were collected pre- and post-activity. A hybrid approach integrating a loss function and respiratory compensation algorithm was developed for spatial registration correction. Results After correction through spatial registration using a mathematical model, the drift range of semi-rigid body surface markers was 0.86 ± 0.11 mm. Specifically, the body surface drift ranges for the left anterior superior iliac spine marker were 0.79 ± 0.12 mm, for the right anterior superior iliac spine marker were 0.85 ± 0.14 mm, and for the pubic symphysis marker were 0.96 ± 0.25 mm. The stability around the umbilicus was relatively poor, with an error range of 1.71 ± 0.91 mm. Among the four markers, three have achieved positioning accuracy meeting the millimeter-level requirements for spatial registration in the current field of medical navigation surgery. The performance complies with the mandated sub-4-millimeter Target Registration Error (TRE) for optical tracking devices in surgical navigation applications. Conclusions The first successful mitigation of surface marker drift issues by a mathematical compensation algorithm enabling binocular vision navigation in pelvic floor surgerys, and lays a foundation for future semi-rigid anatomical structure navigations.