Use of a Radar Reflector Surgical Guidance System for Peripheral Nerve Surgery

Introduction: While radar reflector localization of breast lesions has seen increased application, its utility in peripheral nerve surgery has not been well established. Current imaging-guided and wired preoperative approaches to localization present challenges such as wire displacement, patient discomfort, low precision, and requirement for short time interval between marking and surgery. In this case series, we assess a nonradioactive radar reflector system as a novel localization method in peripheral nerve surgery.

Methods: Patients planned for peripheral nerve surgery underwent preoperative placement of one or more 12x1.6 mm reflectors, and a radar detector reporting distance to reflector was used for intraoperative guidance. We retrospectively reviewed the indications for surgery and use of the guidance system, success of reflector localization and retrieval, and adverse outcomes.

Results: Between September 2023 and September 2024, 21 patients (aged 22-93, 14 male) underwent peripheral nerve surgery and had reflectors placed preoperatively at a single tertiary care center. Reflector placement by ultrasound radiologists occurred between 0 and 164 days before surgery. Surgeries were performed by two peripheral nerve surgeons and included (1) nerve sheath tumor resection (N=7), (2) nerve exploration/neurolysis/repair (N=10), and (3) nerve transfer (N=4). Indications for use of the guidance system in group 1 included prior surgery or radiation, small or deep nonpalpable tumors, and early delineation of margins in large tumors to limit dissection. Indications in groups 2 and 3 included prior surgery or trauma, need for deep dissection/high patient BMI, and need to identify focal pathologies such as neuromas or transected nerve endings. In all cases, implanted reflectors were successfully located and removed intraoperatively. There were no morbidities associated with localizer use at latest follow-up.

Conclusion : The use of a radar reflector guidance was safe and, in our experience, valuable in this cohort of 21 patients undergoing a variety of peripheral nerve surgeries.