Introduction
Perineal radical prostatectomy (PRP) is not a novel concept, and it has been over a century since its first description by Young. Young reported a case series including 10 operations in 1905. PRP was the mainstream way to perform prostatectomy for decades. More than seven decades later, Reiner and Walsh described an anatomical approach to dorsal vein and the Santorini plexus via retropubic radical prostatectomy. Subsequently, Walsh and Donker described the anatomic nerve-sparing radical prostatectomy. This retropubic approach allowed lymph node dissection through the same incision. The retropubic approach was adopted globally over time and became the gold standard approach to treat localized prostate cancer, and later locally advanced prostate cancer as well. Efforts to decrease morbidity resulted in laparoscopic radical prostatectomy, and subsequently, robotic radical prostatectomy. The minimally invasive techniques followed the retropubic approach. As the field moved towards robotic surgery, the experience and interest in the perineal approach waned over the decades.
The initial robotic platforms required multiple ports placed in a large enough working space to perform surgery. For the perineal approach, this is not feasible because of anatomical constraints such a narrow, deep working space. Human anatomy makes it impossible to perform multi-port robotic surgery in such a small anatomical space. In our initial experience, laparoendoscopic single-site surgery offered a possible option using the da Vinci Si multi-port surgical platform. However, the currently available da Vinci Xi and Si platforms were not purpose built for single-port surgery, which created ergonomic problems such as instrument clashing. In 2018, the da Vinci single-port (SP) surgical platform was approved by the US FDA for use in the clinical setting. The SP platform is a purpose-built single-port platform and therefore eliminates many ergonomic issues related to the perineal surgical field. Since the adoption of the SP platform, we have performed PRP exclusively with this platform. Therefore, our technical focus will be on the SP platform, even though our initial experience was with the multi-port platform.
Patient selection
In our practice, we perform robotic radical prostatectomy via the abdominal approach according to the guidelines. , We perform transperitoneal retropubic, extraperitoneal retropubic, and perineal robotic radical prostatectomies. There are no fixed criteria to recommend one approach over the other. We generally offer perineal approach as an alternative in select cases. To adequately perform any robotic surgery, we need to establish pneumoperitoneum, and we need a nonhostile surgical field. In most cases, adhesions can be lysed to allow appropriate port placement and perform surgery. However, suboptimal conditions such as previous extensive abdominal surgeries, previous radiotherapy, transplanted kidney in the pelvic fossa, and permanent colostomy/ileostomies make the abdominal approach difficult or impossible at times. In these select conditions, the extraperitoneal retropubic approach is considered an alternative. However, in the majority of these conditions, developing extraperitoneal space is not always possible. There is risk of peritoneotomy and injury to intraabdominal organs. Therefore, perineal robotic radical prostatectomy is a very reasonable alternative to avoid hostile abdominal working space.
Furthermore, additional comorbidities play a role in patient selection. In patients with restrictive respiratory conditions such as morbid obesity or restrictive lung diseases, perineal approach is a reasonable alternative due to positioning of the patient. Perineal robot-assisted radical prostatectomy (RARP) is performed with supine positioning, which eliminates the need for pneumoperitoneum. And thus, we avoid the cranial and cardiopulmonary negative effects of steep Trendelenburg and pnumoperitoneum. ,
Robotic instruments needed
The da Vinci SP platform uses a multichannel port that allows insertion of three instruments and a camera in a straight configuration ( Fig. 32.1 ). The robotic instruments used are monopolar scissors, Maryland bipolar forceps, Cadiere forceps, two needle drivers, and Weck Hem-o-lok clip applier. The Gelpoint Mini Advanced Access Platform (Applied Medical, Rancho Santa Margarita, CA) is required for docking. For insufflation the AirSeal (ConMed, Utica, NY) system is used through a system-specific 12–15 mm assistant trocar ( Fig. 32.2 ).
Preoperative planning and positioning
Preoperative patient planning is similar to abdominal robotic radical prostatectomy. Anticoagulants are stopped according to the half-life of each medication, and medication is switched to low molecular weight heparin, which is not administered the morning of surgery. Bowel preparation is not mandatory, and preoperative enema can be performed at the discretion of the surgeon. Blood typing and screening are recommended in case of bleeding.
After placement of lines and monitorization, general anesthesia is induced. Sequential compressive devices are placed on the bilateral lower extremities. Third-generation cephalosporins are recommended as antibiotic prophylaxis and continued until discharge. The patient is positioned in an exaggerated lithotomy position with 15 degrees of Trendelenburg, arms are tucked, and all pressure points are padded. Afterwards, the patient is prepped and draped in a sterile fashion. A Foley catheter is inserted sterilely on the field and placed for gravity drainage ( Fig. 32.3 ).
Perineal access, port placement, and docking
Before the incision is made, a glove is sutured to the anus to help feel the rectum during surgery without losing sterility. A 3-cm semicircular incision is made in the midline between the ischial tuberosities ( Fig. 32.4 ). The subcutaneous tissue is dissected, and the central tendon is identified and incised. After further dissection, the rectourethralis muscle is divided, and the external urethral sphincter is retracted superiorly. The levator ani muscles are split, exposing the prostate in the midline. After development of the subcutaneous tissue, suspension sutures are placed and passed through a small scrotal incision for upward retraction. Gelpoint Mini Advanced Access Platform is deployed. The dedicated 25-mm SP port, an extra 12–15 mm AirSeal (ConMed, Utica, NY) assistant port, and a flexible suction tube are placed through the gel cap. The robot is then air docked ( Fig. 32.5 ). The rationale for air docking is the engineering design of the SP platform. As per the design, the surgical site should be approximately 10 cm from the distal end of the SP cannula. However, the prostate is much closer to the skin than this optimal distance. To create adequate distance the floating docking technique is used. Air docking increases the working space of the instruments by more than 390%. Initially, monopolar scissors, Maryland bipolar forceps, and Cadiere forceps are used. Robotic needle drivers and clip appliers are used in the later stages of the surgery.
Posterior dissection
The prostate dissection generally starts on the posterolateral sides to expose levator ani muscle fibers. The initial goal is to identify the Denonvilliers fascia and identify a posterior plane ( Fig. 32.6 ). However, because of our patient selection, extensive scars may be seen due to previous surgeries. Once Denonvilliers fascia is identified and incised, the dissection advances in the cephalad direction along the length of the prostate. Cross-communicating nerve fibers have been described in the past; therefore Denonvilliers fascia is generally spared and left with the patient. However, a more aggressive dissection can be performed based on the tumor stage.
Seminal vesicles, vas deferens dissection
The vas deferentia and seminal vesicles are identified at this point and dissected out ( Fig. 32.7 ). The vasa deferentia are divided, dissected, and later transected. The medial space between the two seminal vesicles is an avascular plane, which is a good starting point for the dissection. The dissection continues circumferentially to reach the tip of the seminal vesicles. The majority of the blood supply entering the seminal vesicles is through the tip artery, which can be clipped or cauterized. We complete the dissection bilaterally before proceeding with lateral pedicle dissection.
