RT Journal Article SR Electronic T1 Potential value of 3D Volume Rendering using PSMA PET/CT to improve surgical planning for salvage lymph node resection: the UCLA initial experience JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP P1112 OP P1112 VO 64 IS supplement 1 A1 Ells, Zachary A1 Farolfi, Andrea A1 Reiter, Robert A1 Donin, Nicholas A1 Shirk, Joseph A1 Zhang, JJ A1 Weiner, Adam A1 Calais, Jeremie A1 Dahlbom, Magnus YR 2023 UL http://jnm.snmjournals.org/content/64/supplement_1/P1112.abstract AB P1112 Introduction: Salvage lymphadenectomy for node-recurrent prostate cancer can be a challenging operation because the involved lymph nodes (LN) can be difficult to locate and resect due to their small size, difficult to access location, and the interindividual variation in deep retroperitoneal pelvic anatomy. Traditionally, surgeons have relied on 2D imaging from cross-sectional imaging studies such as CT, MRI, and PET/CT, to visualize, plan, and perform these procedures. But 2D imaging can be a challenging substrate from which to cognitively generate a 3D surgical roadmap, and can lead to challenges in identifying and resecting the involved nodes. We hypothesize that through the creation of 3D volume renderings, surgeons may be able to more easily and accurately devise a 3D surgical roadmap, leading to improved ability to locate and resect the involved LN. In this project, we used 2D preoperative imaging data to create 3D volume anatomic renderings for use during the planning and intraoperative guidance of robotic salvage lymphadenectomy for prostate cancer. We aimed to determine the feasibility, and utility of these 3D volume renderings.Methods: Pre-operative 68Ga-PSMA PET/CT scans of patients scheduled to undergo robotic-assisted pelvic LN dissection were used. First, Osirix was used to view and download the DICOM images from the PACS server. Second, 3D Slicer (open source) was used for precise segmentation and the creation of 3D volume renderings. After the anatomy of interest for pelvic LN resections were contoured, a 3D volume rendering was created and exported as an .OBJ file with an accompanying .MTL file. After manipulation of the .MTL file to restore color, and texture to the .OBJ file, both were uploaded into the final software, Autodesk Viewer. Using three independent software in the creating of the 3D volume renderings, surgeons could accurately visualize their patient prior to, and during the surgery.Results: This preliminary case series included four patients who underwent radioguided pelvic LN resection. Using 68Ga-PSMA PET scan acquired on average 144 ± 58 days prior to surgery, we were able to create a 3D renderings which the surgeons could utilize before and during the surgery. In these four cases, patients exhibited 2, 2, 3, and 4 LNs expressing 68Ga-PSMA uptake on the PET respectively with SUV ranging between 1.6 – 5.9. All target LNs were successfully removed during surgery. Using Osirix, 3D Slicer, and Autodesk to create the 3D renderings took an average of an hour, but timing continuously improved with experience and increased computational power. Conclusions: Through the use of Osirix, 3D Slicer, and Autodesk Viewer we created 3D volume renderings, optimal for pre-surgery viewing and planning purposes without any additional cost. The method we propose is free, open-source, and multifunctional and could be applied to any procedure requiring careful and strategical anatomic planning.