Multicenter Prospective Comparative Study of Patient Radiation Doses in Localization Techniques for Small Lung Lesions.

Background/Objectives: Although surgeries employing cone-beam computed tomography (CBCT) for small lung lesions have been reported, the association between CBCT scan frequency and patient radiation exposure remains unclear. This study aimed to investigate patient radiation doses from CBCT during thoracic surgeries, and the patient radiation doses were compared with those from other preoperative marking methods. Methods: This multicenter prospective study included 81 patients who underwent surgery for small lung lesions requiring marking between January 2021 and June 2024 at three institutions. CBCT-guided surgeries involved the use of metal clips in a hybrid operating room with 1-4 scans, depending on the lesion. For other preoperative marking methods, hook-wire or virtual-assisted lung mapping (VAL-MAP) was used. Patient radiation doses were measured using wearable dosimeters at five anterior thorax sites, and the total dose was compared across methods. Results: The study included 81 patients: CBCT (n = 61), VAL-MAP (n = 10), and hook-wire (n = 10). CBCT cases were distributed as follows: single scan (n = 10), double scans (n = 34), triple scans (n = 15), and quadruple scans (n = 2). The radiation doses were 86.9 ± 61.7 mGy for hook-wire, 39.8 ± 27.5 mGy for VAL-MAP, and 11.0 ± 6.5 mGy for single-scan CBCT, 17.3 ± 7.8 mGy for double scans, 23.1 ± 14.0 mGy for triple scans, and 22.7 ± 0.1 mGy for quadruple scans. Although radiation exposure increased with more CBCT scans, performing up to triple scans resulted in significantly lower exposure compared to other methods. Conclusions: Intraoperative CBCT is a feasible and safe technique for identifying small lung lesions, providing lower radiation exposure compared to other preoperative localization methods.