Robot-assisted Nerve Plane-sparing Eradication of Deep Endometriosis with Double-bipolar Method

To demonstrate anatomic and technical highlights of a robot-assisted nerve plane-sparing eradication of deep endometriosis (DE).

Stepwise demonstration of the technique with narrated video footage.

An urban general hospital.

Laparoscopic nerve-sparing techniques as represented by the Negrar method reportedly result in lower rates of postoperative bladder, rectal, and sexual dysfunctions than classical approaches [1]. In addition, robotic surgery has become available, and 2 meta-analyses have confirmed that robotic surgery is safe and feasible for the treatment of endometriosis, especially in advanced cases [2,3]. However, few papers have shown the surgical techniques for a nerve-sparing procedure using a robotic approach. The patient was a 45-year-old woman who presented with severe chronic pelvic pain and dysmenorrhea resistant to medication therapy. She had no nerve-specific complaints such as pain in the pudendal distribution or a voiding dysfunction. Magnetic resonance imaging revealed multiple uterine fibromas and adenomyosis with DE, involving the uterosacral ligament and surface of the rectum, with cul-de-sac obliteration. The parametrium was not involved in the DE. Robot-assisted nerve plane-sparing excision of DE with a double-bipolar method was performed using the following 8 steps: step 1, adhesiolysis and adnexal surgery; step 2, checking the ureteral course; step 3, separation of the nerve plane (step 3.1, dissection of the avascular layer below the hypogastric nerve, between the prehypogastric nerve fascia and presacral fascia; and step 3.2, dissection of the avascular layer above the hypogastric nerve, between the prehypogastric nerve fascia and fascia propria of the rectum) [4,5]; step 4, reopening of the pouch of Douglas; step 5, complete removal of DE lesions while avoiding injury to the nerve plane; step 6, hysterectomy (if the patient desires non-fertility-sparing surgery); step 7, checking for rectal injury using an air leakage test; and step 8, barrier agents for adhesion prevention. With regard to step 3, as a result of sharp dissection between avascular layers both above and below the hypogastric nerve, autonomic nerves in the pelvis were separated like a sheet with the surrounding fascia (the nerve plane). We then performed steps 4 to 6 in a step-by-step manner while avoiding injury to the nerve plane. The urinary catheter was removed within 24 hours after the surgery, and no residual urine was seen. The patient developed no perioperative complications; in particular, no postoperative bladder or rectal dysfunctions. The precise sharp dissection of the right embryo-anatomic planes on the basis of the detailed mesoanatomy seems important for improving functional outcomes in nerve-sparing surgery [5].

Robot-assisted nerve plane-sparing eradication of DE is as technically feasible as the conventional laparoscopic approach. The step-by-step technique should help surgeons perform each part of the surgery in a logical sequence, making the procedure easier and safer to complete. However, the latent benefits of robot-assisted nerve-sparing surgery in the treatment of DE remain uncertain.