An "alternative finger" in robotic-assisted thoracic surgery: intraoperative ultrasound localization of pulmonary nodules

Aim: Robotic-assisted thoracic surgery (RATS) has become a promising treatment for pulmonary neoplasms. During RATS, intraoperative ultrasonography can act as an "alternative finger" to "touch" and locate lesions, especially pulmonary nodules. This study was aimed to investigate the efficacy of intraoperative ultrasonographic localization during da Vinci RATS procedures. Material and methods: Patients with pulmonary nodules were randomly divided into an Experimental Group and Control Group in which nodules were respectively located using intraoperative ultrasonography or by the surgeon's anatomic knowledge. The success rates and relevant localization factors were compared between the groups and analyzed to conclude the efficacy of intraoperative ultrasonography. Additionally, the intraoperative ultrasonography learning curve was analyzed to evaluate each surgeon's ability to independently perform intraoperative ultrasonography. Results: Thirty-four patients were included in the study (n = 17/group). Respectively, the Experimental Group and Control Group comprised 41.2% and 58.9% women (p=0.937), and had average ages of 55.5 and 55.8 years. In the Experimental group, ultrasonographic localization for mixed ground-glass nodules with CT values of -500 to -100 Hounsfield units had an efficacy of 87.5%. By contrast, the localization efficacy in Control Group was 20.0% (p=0.032). A single surgeon without prior experience performed intraoperative ultrasonography in 20 cases, and the latter 10 procedures required significantly less time relative to the former 10 procedures (p=0.000). Conclusions: During RATS, the use of intraoperative ultrasonography as an "alternative finger" to "touch" and find the accurate location of pulmonary nodules, especially mixed ground-glass nodules, is warranted.