Feasibility and safety of a robotic-assisted optical navigation system for pulmonary nodule percutaneous cryoablation: a prospective, single-center, single-arm pilot study

Background Percutaneous cryoablation under imaging guidance is an effective therapeutic modality for pulmonary nodules, but the conventional technique relies on surgical complexity and physician experience. Computed tomography (CT)-guided robotic-assisted percutaneous puncture technique provides three-dimensional (3D) reconstruction, optimal needle trajectory planning, and monitoring of real-time respiratory motion, thereby enabling safe ablation of lung nodules. This study aimed to clinically evaluate the feasibility and safety of a robotic-assisted optical navigation system when utilized for CT-guided percutaneous cryoablation of pulmonary nodules. Methods Patients who underwent CT-guided percutaneous cryoablation via a robotic-assisted optical navigation system were prospectively enrolled in our study. The primary outcomes were the technical success rate and the technical efficacy rate, and the preoperative, intraoperative, and postoperative variables were recorded and analyzed for each patient. Results A total of 37 consecutive patients with a single nodule were ultimately enrolled in the present study. The technical success rate was 100%, and the technical efficacy rate of robotic-assisted cryoablation was 100% with no recurrence during the 1-month follow-up. The average number of needle adjustments per nodule was 0.82 ± 1.19 in this study, with a mean deviation of 3.47 ± 2.47 mm. The mean numbers of CT acquisitions and dose length products (DLPs) used during needle insertion were 3.44 ± 1.65 and 638.86 ± 434.44 mGy*cm, respectively. The duration of needle placement was 15.95 ± 5.06 min, whereas the total procedural duration was 99.32 ± 32.00 min. Notably, the deviation was found to be significantly correlated with the lobar location and was more prominent in the lower lobe. However, no significant correlations were observed with the nodule type, size, distance to the pleura, chest wall thickness, needle trajectory length, decubitus position, or the pulmonary function status of the patient. Moreover, no significant changes were found in the pulmonary function of the patients before or after the treatment. No major grade ≥ 3 complications were observed. However, among the minor complications, there were 5 cases (13.51%) of immediate pneumothorax, 2 cases (5.41%) of delayed pneumothorax, and 1 case (2.70%) of hemorrhage. Conclusion The robotic-assisted optical navigation system is feasible, safe and effective for CT-guided percutaneous cryoablation of pulmonary nodules.