A free method for patient-specific 3D-VR anatomical modeling for presurgical planning using DICOM images and open-source software.

Introduction: Surgeons commonly use cross sectional images to plan and prepare for surgical procedures. However, cognitively translating 2D images to surgical settings can be difficult and lead to sub-optimal resections. Lymph node dissection can be challenging due to the inability to locate small metastatic lesions, and their proximity to at-risk organ(s). 3D volume rendered (3D-VR) patient specific images can help to address these challenges. We created patient-specific 3D-VR images using freely available open-source programs.

Methods: This study included patients part of the clinical trial NCT04857502. Patients received a PET/CT prior to radioguided surgery. 3D Slicer was used to segment anatomy of interest (organs and tumor lesion(s)). After segmentation, the data was exported as an .OBJ file with an accompanying .MTL file. Manipulation of the .MTL file to restore model properties to the .OBJ file, were completed and both files were uploaded into Autodesk Viewer. Surgeons then received an email link to access the finished 3D-VR model on their smartphone or laptop for peri-operative preparation and/or guidance.

Results: The method was used in a series of 14 patients with prostate cancer undergoing pelvic lymph node dissection with PSMA-radioguided robotic surgery using pre-operative PSMA PET/CT images acquired on average 103 ± 69 days prior to resection. The creation of the 3D-VR models was successfully conducted in all 14 cases. In all cases, the lesions identified on the pre-operative PET/CT imaging 3D-VR models were successfully removed during surgery.

Conclusion: We created patient-specific anatomical 3D-VR models that the surgeons can use for pre-surgical planning and intraoperative tumor localization, by applying free, open-source software that could be used in any procedure requiring careful and strategical planning.