Radar-guided localization system for accurate resection of selected cervical lymph nodes

Abstract

Needle biopsy of cervical lymph nodes is a common method to diagnose metastasis. Excisional biopsy is typically reserved for cases where needle biopsy is nondiagnostic, usually due to sampling error or insufficient cellular material. Locating the target lymph node in the neck can be difficult. A radar-guided localization (RGL) system may overcome this. A 41-year-old man presented with recurrent papillary thyroid carcinoma in the thyroid bed and radiologically suspicious lateral cervical lymph nodes on positron emission tomography–computed tomography. Repeated needle biopsies failed to confirm metastasis in these nodes. A reflector was inserted preoperatively into a lateral cervical lymph node under ultrasound guidance and local anaesthesia, enabling its precise intraoperative identification several weeks later. The node was successfully localized and removed at the time of surgery with minimal dissection of the surrounding tissues. RGL is a wire-free, nonradioactive localizer that facilitates accurate intraoperative identification of small, nonpalpable lymph nodes in anatomically complex areas such as the neck. The reflector can be placed in the target node at any time prior to surgery and may overcome the limitations of conventional localization techniques to improve surgical precision and outcomes in head and neck oncologic surgery.