# New Evolution of Robotic Radical Prostatectomy: A Single Center Experience with PERUSIA Technique
## 2 Materials and Methods  
After an extensive experience in \"open\" and laparoscopic RP, 1010 extraperitoneal RARP were performed from April 2011 to April 2020 in our high-volume center. During this experience in robotic surgery, we developed an innovative technique called PERUSIA (Posterior, Extraperitoneal, Robotic, Under Santorini, Intrafasical, Anterograde), which is aimed at preserving not only the neurovascular bundles but also the entire Veil of Aphrodite and the anterior perivrostatic structures, including the venous plexus of Santorini, exploiting extraperitoneal access, with a posterior anterograde intrafacial dissection.  
We retrospectively collected data of 800 RARP performed using the PERUSIA technique from January 2012 to October 2019. We included in this study all clinical low-risk PCa in accordance with the categories of prognostic risk of the European Association of Urology Guidelines with life expectancy \(\geq\) 10 years, who were fully continent and sexually potent with 5-item International Index of Erectile Function (IIEF-5) score \(\geq\)17 and did not accept active surveillance. Exclusion criteria were life expectancy <10 years, the first 50 cases of PERUSIA technique, which was considered as learning curve series, positive biopsy in anterior prostatic zone, pre-operative urinary incontinence, patients with neuro-urological lower urinary tract symptoms, erectile dysfunction (IIEF-5 < 17), and monolateral nerve-sparing. All patients were assessed through memorial Sloan-Kettering PCa nomograms to evaluate lymph node involvement risk and to predict the post-operative probability of cancer remaining progression-free [11]. An internal review board approved the study, and written consent was obtained from patients.  
We evaluated peri-operative outcomes (operative time, estimated blood loss, catheterization time, complication rate, length of stay) as well as oncological and functional outcomes. Surgical complications were evaluated according to the Clavien-Dindo Classification system.  
Oncologic outcomes were evaluated in terms of Positive Surgical Margins (PSMs) and Biochemical Recurrence (BCR) (defined as prostate-specific antigen (PSA) > 0.2 ng/mL in two consecutive evaluations) at a median follow-up of 47 mo (interquartile range (IQR) 24-66 mo). Urinary continence was evaluated through direct interview according to question number 5 of the Expanded Prostate Cancer Index Composite (EPIC) questionnaire [12]. We evaluated urinary continence at 1 day after catheter removal (immediate), at 3 (early), and 12 months after surgery; patients using no pad were considered as fully continent, patients using 1 pad were considered as slightly incontinent, while patients using >1 pad were accounted as incontinent.  
Sexual potency was evaluated using the 5-item International Index of Erectile Function test pre-operatively and at 3, 6 and 12 mo after surgery. Specifically, patients were defined as potent when IIEF-5 score was >17 with or without drug. Follow-up consisted of medical examination, PSA measurement, administration of IIEF-5 questionnaires, and self-reported urinary incontinence. Data were analyzed with GraphPad Prism6.0; the significance threshold was set at 0.05.