Vein watershed analysis locational method versus computed tomography-guided percutaneous localization for detecting non-palpable peripheral pulmonary nodules: a real-world study of non-inferiority.

Objectives: In recent years, with the advancement of sublobar resection, a safe, painless method for locating peripheral pulmonary nodules was needed. Previously, an alternative method of arterial watershed localization was introduced to remedy the shortcomings of preoperative computed tomography (CT)-guided localization or other methods for locating pulmonary nodules, but its technical limitations were discovered during clinical applications. Therefore, we developed a technique to localize non-subpleural nodules using basin analysis of the target vein and validated its feasibility and safety.

Methods: We performed a retrospective analysis of surgical cases of pulmonary nodules smaller than 2 cm in our centre. The vein watershed locational method (V-WALM) was compared with CT-guided percutaneous puncture localization wedge dissection in terms of success rate, the mean duration of the operation, mean volume of intraoperative bleeding and median postoperative stay, mean postoperative drainage and mean drainage tube indwelling time.

Results: V-WALM and CT-guided localization were used for localized resection of pulmonary nodules in 50 patients. The localization success rates were 94.0% for V-WALM and 90.0% for CT-guided localization, respectively, with no statistical difference noted. In addition, no statistical difference in patient population distribution between the 2 groups was noted. The operating time was 95.5 ± 26.4 min for V-WALM and 94.3 ± 37.5 min for CT-guided localization, with no statistical difference. Neither were there statistical differences in intraoperative bleeding, postoperative drainage and drainage tube indwelling time. The lymph node sampling rate of V-WALM was 48.0%, which was much higher than the 24% noted in the CT-guided localization group.

Conclusions: The results of this study demonstrate that V-WALM is a safe and feasible intraoperative localization method for peripheral lung nodules. It provides a high-precision, fast and minimally invasive approach to intraoperative localization.