In robot-assisted partial nephrectomy (RAPN), renorrhaphy techniques include single-layer and double-layer suturing. Compared to traditional double-layer renorrhaphy, single-layer renorrhaphy shortens ischemic time and may reduce damage to healthy tissue, though it could raise the risk of leakage. We introduce our hybrid approach, combining selective inner layer clipping (SILC) during resection, guided by AI-assisted 3D navigation and Doppler ultrasonography. This enables simultaneous resection and inner layer closure, reducing ischemic time and preserving renal function by sparing critical vasculature. The outer layer closure provides added support, addressing leak concerns.

We present the case of a 50-year-old man who underwent left RAPN. Arterial, portal, and delayed phase images were obtained at 1 mm cuts, and an RUS™ AI-based 3D kidney model was reconstructed (Hutom, South Korea). Intraoperatively, the Da Vinci surgeon identified vascular supply using robotic ultrasonography and the AI 3D model. We performed enucleoresection combined with inner cortical clipping of feeding vessels using Click'aV® polymer ligating clips (Grena, UK), Challenger® Ti-P (B.Braun, UK), or Small or Medium-large clip applier (Intuitive Surgical Da Vinci, US). After resection, the site was inspected for bleeding, followed by outer layer renorrhaphy using Vicryl 2-0, Click'aV® clips, and LAPRA-TY™ Suture Clip Applier (Ethicon, US).

The patient presented with a 5.6 cm cystic mass in the upper pole of the left kidney. Color Doppler ultrasound revealed one arteriole, and the AI 3D model identified one arteriole and one venule. Three cysts were completely excised: a Bosniak III main mass, a Bosniak II cyst adjacent to the renal mass, and a small simple cyst. During enucleoresection, the two aforementioned vessels were identified. One additional venule was found, but as significant vessels were controlled in advance, the operation proceeded smoothly. The feeding vessels were ligated and cut using SILC. The warm ischemic time was 23 minutes. Pathology revealed the main mass as clear cell renal cell carcinoma with extensive cystic change (5.4×4.4×3.4 cm³, pT1b), with a clear resection margin. The adjacent renal cyst was diagnosed as a multilocular cystic renal neoplasm of low malignant potential, with a clear resection margin (2.9×2.3×0.4 cm³). The other cyst was a simple cortical cyst. Preoperative and postoperative serum creatinine levels were 0.84 and 0.79, respectively, with a glomerular filtration rate ≥ 90 in both cases. The patient was discharged on postoperative day 4 without complications.

Our experience with SILC and hybrid renorrhaphy for RAPN, aided by AI 3D navigation and Doppler sonography, demonstrates that concise tumor resection and renorrhaphy is feasible without complications. Larger studies are warranted to validate these findings.