Safety and feasibility of bronchoscopic indocyanine green–methylene blue versus CT-guided autologous blood–methylene blue localization for pulmonary nodules: a propensity score–matched analysis

BACKGROUND: Preoperative localization may facilitate intraoperative identification of selected small, subsolid, or poorly palpable pulmonary nodules during video-assisted thoracoscopic surgery (VATS). This study compared the safety and feasibility of bronchoscopic indocyanine green plus methylene blue (ICG + MB) localization with CT-guided autologous blood plus methylene blue (blood + MB) localization. METHODS: This single-center retrospective study included patients who underwent preoperative localization for selected pulmonary nodules between October 2019 and October 2025. Propensity score matching with replacement was performed using age, sex, body mass index, nodule size, and shortest distance to the pleura as covariates. Outcomes included localization success, post-localization pneumothorax, intraoperative visibility score (0-5), and localization time. Firth logistic regression was used to identify factors associated with post-localization pneumothorax. RESULTS: After matching, 17 patients in the bronchoscopic ICG + MB group and 41 unique patients in the CT-guided blood + MB group were analyzed. Localization success rates were comparable (94.1% vs. 90.2%, p = 1.000), and visibility scores did not differ significantly (p = 0.210). Pneumothorax occurred in 22.0% of the CT-guided group and in none of the bronchoscopic group (p = 0.047). CT-guided localization (OR = 9.85, 95% CI: 1.09-1307.06; p = 0.039) and WBC count (OR = 1.46, 95% CI:1.03-2.24; p = 0.036) were associated with pneumothorax. The model yielded an AUC of 0.810. CONCLUSIONS: In this matched cohort, bronchoscopic ICG + MB localization showed localization success and intraoperative visibility comparable to CT-guided blood + MB localization. Pneumothorax occurred less frequently in the bronchoscopic group. Bronchoscopic localization may represent a feasible airway-based option for selected nodules when preoperative localization is considered necessary and avoidance of pleural puncture is preferred.