The Utility of Indigo Carmine and Lipiodol Mixture for Preoperative Pulmonary Nodule Localization before Video-Assisted Thoracic Surgery

Purpose: To evaluate the safety and efficacy of a mixture of indigo carmine and lipiodol (MIL) as a marker of pulmonary nodule before video-assisted thoracic surgery (VATS). Materials and Methods: One hundred sixty-eight sessions of pulmonary marking were performed using MIL before VATS for 184 nodules (mean size, 1.2 +/- 0.6 cm; range, 0.3-3.6 cm) on 157 patients (83 men and 74 women; median age, 66 years). The mean distance between the lung surface and the nodule was 0.8 +/- 0.7 cm (range, 0-3.9 cm). MIL was injected near the nodule using a 23-gauge needle. Mean number of 1.2 +/- 0.4 (range, 1-3) punctures were performed in a session for the target nodules, with mean number of 1.1 +/- 0.3 (range, 1-3). Successful targeting, localization, and VATS were defined as achievement of lipiodol accumulation at the target site on computed tomography, detection of the nodule in the operative field by fluoroscopy or visualization of dye pigmentation, and complete resection of the target nodule with sufficient margin, respectively. Results: The successful targeting rate was 100%, and the successful localization rate was 99.5%, with dye pigmentation for 160 nodules (87.0%) and intraoperative fluoroscopy for 23 nodules (12.5%). Successful VATS was achieved for 181 nodules (98.4%). Two nodules (1.1%) were not resectable, and surgical margin was positive in 1 nodule (0.5%). Complications requiring interventions occurred in 5 sessions (3.0%) and included pneumothorax with chest tube placement (n = 3) and aspiration (n = 2). No complication related to the injected MIL occurred. Conclusions: MIL was safe and useful for preoperative pulmonary nodule marking.