CT-Guided Dual-Fluorescent Marking to Localize Small Pulmonary Nodules for Robotic Sublobar Resection: Technical Note...

To describe a CT-guided dual-fluorescent marking technique (methylene blue + indocyanine green stabilized in fibrin-thrombin matrix) for intraoperative localization of non-palpable pulmonary nodules during robotic-assisted thoracic surgery (RATS) and to report feasibility and key outcomes.

Retrospective, single-center series of 84 consecutive patients with solid or subsolid nodules ≤ 2 cm referred for RATS (Oct/2021-Oct/2024). Under general anesthesia, a 22-G Chiba needle was used for CT-guided percutaneous injection of a standardized solution (1 mL 1% methylene blue + 1 mL indocyanine green + 3 mL fibrin-thrombin + 1 mL iodinated contrast; typical injected volume 0.2-1.0 mL). Resection proceeded using near-infrared Firefly® imaging.

intraoperative identification, complete resection, margin status, timing, and complications. Prespecified subgroup analysis compared subsolid vs. solid lesions.

All 84 nodules were localized intraoperatively and resected with negative margins; no conversion to open surgery occurred and no complications attributable to marking were recorded. Mean operative time was 163.7 ± 66.7 min; mean interval between marking and surgery was 74.6 ± 20.6 min. Patients with subsolid nodules were older (70.5 vs. 63.1 years, p = 0.003) and had larger lesions (14.7 vs. 11.4 mm, p = 0.010). During a mean clinical follow-up of 17.3 months, no local recurrences were observed.

CT-guided dual-fluorescent marking is a practical, fluoroscopy-free localization strategy that integrates smoothly with RATS workflows and enables reliable sublobar resections with negative margins in this series. The incremental contribution of methylene blue beyond ICG could not be isolated and warrants prospective evaluation. However, this study did not include a control group, such as conventional marking techniques, which should be considered when interpreting the results.