CT-guided microcoil implantation for localizing pulmonary ground-glass nodules: feasibility and accuracy of oblique approach for lesions difficult to access on axial images

Abstract

Objective: (1) To evaluate the value of CT-guided microcoil implantation for localizing pulmonary ground-glass nodules (GGNs) before video-assisted thoracoscopic surgery (VATS). (2) To evaluate the feasibility, safety and accuracy of cephalic-caudal oblique approach for lesions difficult to access on axial images owing to overlying bony structures, large vessels or interlober fissures. Methods: From June 2016 to March 2019, all patients with GGNs resected by VATS after marking using CT-guided microcoil implantation in China-Japan friendship hospital were enrolled and clinical and imaging data were retrospectively analyzed. According to the microcoil marked path, the GGNs were divided into cephalic-caudal oblique group (oblique group) and non-oblique group. The success rate of marking, the time required for marking and the incidence of complications between the two groups were compared. Results: 258 GGNs from 215 consecutive patients were included in this study. The diameter of GGNs was 1.22 ± 0.50 cm, and the shortest distance from GGNs to the pleura was 1.56 ± 1.09 cm. All 258 GGNs were successfully resected by VATS under the guidance of implanted microcoils, and no case was converted to thoracotomy. During CT-guided microcoil implantation, cephalic- caudal oblique approach was taken in 56 GGNs (oblique group) to avoid bone, interlobar fissure and blood vessels. The time required for marking was significantly longer for oblique group compared with non-oblique group (16.6 ± 2.4 vs. 13.1 ± 1.9 min, p<0.01). No significant differences in the success rate of marking (94.6% vs 91.6%), the incidence of pneumothorax (19.6% vs 17.8%), the bleeding rate (10.7% vs 8.9%), and the hemoptysis rate (1.8% vs 1.5%) were observed between the two groups. Conclusion: CT-guided microcoil implantation can effectively guide VATS to resect GGNs. For GGNs difficult to access on axial images, CT-guided cephalic-caudal oblique approach is feasible, safe, and accurate. Advances in knowledge: CT-guided microcoil implantation can effectively guide VATS to resect GGNs. The marked path with cephalic-caudal obliquity can effectively avoid bone, interlobar fissure and blood vessels, successfully mark GGNs difficult to access on axial images, while keeping the distance from the pleura to the lesion on the marked path as short as possible at the same time.