Virtual-reality robot-assisted inferior vena cava thrombectomy using virtual vascular endoscopy to identify inferior vena cava invasion.

Objective: Partial or segmental inferior vena cava (IVC) resection is indicated for tumor control in patients with renal tumors invading the IVC. This study aimed to introduce a virtual vascular endoscope to assist surgeons in locating IVC invasion, formulate a surgical plan for robot-assisted IVC thrombectomy (RA-IVCT), and evaluate its potential value. Methods: The reconstruction involves building the construction of deep learning models to predict IVC invasion, which were evaluated via intraoperative findings and pathological analysis. Thirty-six patients with renal tumors and IVC thrombi who underwent RA-IVCT between June 2016 and March 2022 were included in the study. A virtual vascular endoscopy was performed based on preoperative CT findings to identify IVC invasion. Based on the extent of IVC wall invasion and the collateral situation, surgeons could decide whether to perform partial or segmental IVC resection during RA-IVCT. Results: Twenty patients were retrospectively analysed for training in virtual vascular endoscopy (the training cohort), and 16 patients were prospectively analysed to evaluate the accuracy of this technique (the validation cohort). Sixteen patients with IVC invasion underwent cavectomy, whereas six patients underwent partial IVC resection. In the validation cohort, pathological analysis confirmed the exact location of IVC invasion in eight of the nine patients, as indicated by virtual vascular endoscopy. Patients who underwent partial IVC wall resection had less lower extremity edema than those who underwent cavectomy. Conclusion: Our initial experience showed that the virtual vascular endoscopy could assist surgeons in identifying IVC invasion and creating a surgical plan for RA-IVCT.