The utility of a modified microcoil device for pulmonary nodule localization: a single-centre prospective study

Video-assisted thoracoscopic surgery (VATS) is the standard treatment for small pulmonary nodules (SPNs), yet accurate localization of non-palpable lesions remains challenging. This study evaluated the efficacy, feasibility, and safety of a novel computed tomography (CT)-guided microcoil localization system for preoperative SPN management.

We developed a novel CT-guided microcoil system featuring a coaxial needle and a retractable coil with a long, visible distal tail to improve stability and intraoperative identification. In this prospective single-arm study, 178 patients with 231 SPNs (≤10 mm, cN0) underwent preoperative localization followed by VATS. The primary endpoint was technical success, defined as deployment within 10 mm of the lesion without fracture, displacement, or dislodgement.

Technical success was achieved in 224 of 231 nodules, yielding a rate of 97.0% (95% CI: 93.7-98.6%). The mean localization time was 4.4 min, and the median coil-to-nodule distance was 4.9 mm. All nodules were completely resected with negative margins on the first attempt and were successfully identified for definitive pathological diagnosis. Complications were infrequent and mild: asymptomatic pneumothorax occurred in 12 cases (5.2%) and minor hemorrhage in 11 (4.8%), none of which required treatment; these rates compare favorably to those of conventional hook-wire systems. Patient pain was negligible, and 97.4% of coils were retrieved with the specimen. Failures occurred in 3.0% of nodules due to wire fracture, dislodgement, or displacement.

This novel microcoil system demonstrated high efficacy, procedural efficiency, and excellent safety, addressing key limitations of existing localization methods.