AUA2023: REFLECTIONS Hood Hydro Concept, Complex Partial Nephrectomy, and Circulating Tumor DNA

By: Vinayak G. Wagaskar, MBBS, MCh Urology, Icahn School of Medicine at Mount Sinai Hospital, New York, New York; Ketan Badani, MD, FACS (Hon), Icahn School of Medicine at Mount Sinai Hospital, New York, New York; Peter Wiklund, MD, Icahn School of Medicine at Mount Sinai Hospital, New York, New York; Ash Tewari, MD, MCh, Icahn School of Medicine at Mount Sinai Hospital, New York, New York | Posted on: 20 Jul 2023

Figure. Hydro hood technique. EPF indicates endopelvic fascia.

Robot-assisted radical prostatectomy is unique because it has to accomplish 3 competing goals: cancer control, urinary continence, and recovery of sexual function. While cancer control is the most important goal, patients’ quality of life is equally important since patients have to live with the results of the surgery for a long time after beating this cancer. Continence in men is achieved by delicate and well-orchestrated interplay between a group of muscles (both smooth and voluntary), anchored to fixed bony and ligamentous structures, complemented by cushioning effect of mucosa and surrounding soft and fascial tissue. Intact innervation helps in coordinated squeeze of muscles (sphincters) and relaxation of bladder muscles while angulation between bladder and urethra helps in further closure of bladder outlet, especially in times of increased stress such as coughing or sneezing. The concept of a “trizonal neural hammock” revealed that the periprostatic nerves are located in discrete regions around the prostate forming a “hammock-like” architecture. The return to urinary continence and recovery of erectile function are enhanced by the characterization of grades of nerve sparing, in which various levels of periprostatic fascial dissection are employed to optimize nerve preservation on a case-by-case basis. Our “hood technique” is unique in that it uses an anterior approach to preserve the contents of the space of Retzius during robot-assisted radical prostatectomy (see Figure).1-3 Upon removal of the prostate, the preserved tissue has a “hood-like” appearance, comprised of the detrusor apron, arcus tendineus, puboprostatic ligament, anterior vessels, and some fibers of the detrusor muscle. The hood effectively encloses and protects the membranous urethra, external sphincter, and supportive structures without compromising margin rates or biochemical recurrence rates. Our team has revolutionized technique of hydrodissection that facilitates intraoperative visualization of periprostatic nerves. The injection of saline solution at low pressures promotes an atraumatic dissection of the neural hammock, optimizing erectile function outcomes. Additionally, the use of intraoperative microultrasound enhances oncologic safety when dissecting the fascia layers in individuals who have a higher risk of extracapsular extension. Compared to the standard technique, the saline assisted facial engorgement does not lengthen the procedure or increase complications. Besides, it is easy to learn and perform, producing superior functional results, similar positive surgical margin rates, shorter operating times, and less blood loss compared to the standard technique.

The Comprehensive Kidney Cancer Center at Mount Sinai Health System is proud to host our annual innovations conference. Led by Ketan Badani, MD, FACS (Hon), the goal of the session is to discuss the tips and tricks for complex robotic partial nephrectomy and retroperitoneal approaches.

We have assembled an expert panel to discuss the nuances and challenges during the video stream. Our aim is to share our knowledge and expertise with other medical professionals to help expand access to partial nephrectomy in challenging clinical scenarios.

Our focus for this edition is to showcase the benefits of standardizing surgical technique, establishing efficient operating room teams, maintaining continuity and precision in surgical steps, and utilizing advanced technology. These practices have proven to yield optimal clinical outcomes, particularly in the management of challenging high-complexity renal tumors

Utilizing cutting-edge technology is a cornerstone of our approach. As a team, we are passionate about pushing the boundaries of kidney cancer diagnosis through the implementation of innovative imaging techniques such as radiomics and microultrasound, as well as exploring the potential of translational medicine and artificial intelligence. Our commitment to this is also exemplified by our standardized use of intraoperative ultrasound, indocyanine green dye, and 3D models. We are proud to share the wealth of knowledge the collective group has accumulated over the years with the urological community.

The Mount Sinai Bladder cancer program, led by Peter Wiklund, MD, along with his colleagues John Sfakianos, MD, and Reza Mehrazin, MD, has explored the role of circulating tumor DNA–based molecular residual disease in a real-world cohort of patients with bladder cancer who underwent curative-intent cystectomy. Our results showed circulating tumor DNA beneficial for decision-making in patients who may benefit from neoadjuvant and adjuvant therapy, assessing molecular residual disease, and monitoring treatment response.

  1. Tewari A, Takenaka A, Mtui E, et al. The proximal neurovascular plate and the tri-zonal neural architecture around the prostate gland: importance in the athermal robotic technique of nerve-sparing prostatectomy. BJU Int. 2006;98(2):314-323.
  2. Wagaskar VG, Mittal A, Sobotka S, et al. Hood technique for robotic radical prostatectomy-preserving periurethral anatomical structures in the space of Retzius and sparing the pouch of Douglas, enabling early return of continence without compromising surgical margin rates. Eur Urol. 2021;80(2):213-221.
  3. Pedraza Bermeo AM, Wagaskar VG, Schlussel K, et al. Saline-assisted fascial engorgement nerve preservation guided by microultrasound during robot-assisted radical prostatectomy. Videourology. 2022;10.1089/vid.2022.0025.