Robotic Transurethral Vesicourethral Anastomosis after Radical Prostatectomy in Validated Models.

PURPOSE: Techniques that minimize dissection of neurovascular structures and the pelvic floor during radical prostatectomy improve perioperative outcomes and functional recovery. Previous groups have tried to reduce dissection by performing a transurethral prostatectomy. However, the vesicourethral anastomosis could not be reliably performed because of the limited instrumentation. We sought to address this with a concentric tube robot (CTR) system designed specifically for performing a transurethral vesicourethral anastomosis after transurethral prostatectomy, in a series of validated phantoms.

MATERIALS AND

METHODS

We have constructed a CTR system specifically for transurethral surgery. The robot features needle-sized robotic arms that pass through a rigid transurethral endoscope and are composed of telescoping, curved, elastic tubes. By axially rotating these tubes and telescopically extending them, our robot provides surgeons with two small arms that can bend and elongate at the tip of a standard-sized endoscope. This enables suturing within the small lumen of the urethra. We evaluated the CTR in performing the vesicourethral anastomosis in a series of validated phantoms, after transurethral radical prostatectomy was performed manually with a fiber laser. Anastomosis success was evaluated using a leak test. Additionally, we evaluated the surgical time of prostate resection and the suturing time of vesicourethral anastomosis.

RESULTS

We performed transurethral radical prostatectomy and subsequent vesicourethral anastomosis in 11 phantoms. A successful anastomosis was performed in 10 out of 11 (91%) experiments. The median time of resection was 19 minutes (IQR: 18-21 minutes). The median suturing time was 103 minutes (IQR: 91-115 minutes).

CONCLUSIONS

We demonstrated the use of a CTR system to perform a transurethral vesicourethral anastomosis in a series of experiments using validated phantoms. Our CTR overcomes the main barrier for providing a natural-orifice approach to radical prostatectomy by enabling intraluminal completion of the vesicourethral anastomosis.