Computer Tomography-Guided Pulmonary Microcoil Insertion for the Localisation of Small Pulmonary Nodules at the Time of Pulmonary Resection.

Background Small and ground glass pulmonary nodules pose a surgical and diagnostic challenge, with an increase in identification expected with the roll-out of lung cancer screening in Australia. Accurate preoperative localisation of small pulmonary nodules can be a useful adjunct to lung resection in nodules that are not palpable. Various methods have been trialled including methylene blue dye injection and hook-wire placement; however, these are limited by dye diffusion, wire dislodgement, and patient discomfort. CT-guided insertion of a microcoil is a technique of localisation that provides a stable and visible marker on X-ray, improving intraoperative identification. This study reports an Australian institutional experience with this technique and evaluates its safety and efficacy. Methods A retrospective review of all patients undergoing CT-guided pulmonary microcoil localisation followed by video-assisted thoracoscopic surgery (VATS) was conducted at the Alfred Hospital, Melbourne. A case series of 19 patients from 2021 - 2025 was identified and data on technical success, complications, operative outcomes, and pathology were collected. Results The mean patient age was 63.5 years, with a slight male predominance (n=11, 57.8%). Indications for lung resection included pulmonary metastasectomy (n=12, 63.2%) and primary lung adenocarcinoma (n=7, 36.8%). The indication for microcoil guidance was a deep nodule in 36.8% (n=7) of cases and in 63.1% (n=12) of cases an impalpable nodule due to small size or ground glass appearance. The technical success of microcoil placement was 94.3% (n=18), with one displaced microcoil early in the series. No pneumothorax requiring intervention occurred and no major radiological complications from microcoil placement seen in the series. All lesions were successfully resected, with clear histologic margins and no major surgical complications. The mean chest drain duration was 3.4 days and mean hospital stay 4.6 days. Conclusions CT-guided pulmonary microcoil insertion is a safe, reliable, and reproducible technique for intraoperative identification of small or impalpable pulmonary nodules. It addresses some of the limitations of previous localisation methods and demonstrates excellent outcomes in an Australian setting. Future developments may include indocyanine green-coated microcoils for fluorescence guidance during robotic-assisted thoracic surgery.