Laparoscopic Identification of the Inferior Hypogastric Nerve for the Gynecologist

OBJECTIVE The aim of the study was to demonstrate how to identify and preserve the inferior hypogastric nerve (IHN) during gynecological laparoscopic surgeries, in cases where the nerve is not infiltrated by pathological processes such as deep endometriosis. The IHN is liable to injury during gynecological surgery, which may lead to vaginal and cervical hypoesthesia, diminished vaginal lubrication, urinary retention, or anorectal dysfunction.[1] DESIGN Narrated surgical video. Institutional Board Review approval is not required, patient consent obtained. PATIENT A 40-year-old patient with chronic pelvic pain. Imaging suggested the presence of a 4-cm right ovarian hemorrhagic cyst. No evidence of deep endometriosis was detected on imaging or laparoscopy. Excision of the Douglas pouch peritoneum histologically confirmed the presence of superficial endometriosis. INTERVENTIONS Laparoscopic removal of ovarian cyst (not demonstrated) and excision of Douglas pouch peritoneum. RESULTS Routine 4-port laparoscopy was performed. We focus on the patient’s left side: Initially, a superficial incision is made on the peritoneum, at the level of the ureter crossing the left common iliac vessels. Using blunt and sharp dissection, the ureter is mobilized carefully, with its vascular supply intact, and pushed laterally, off of the posterior leaf of the broad ligament. The IHN derives from the superior hypogastric plexus and is located 2 cm below and parallel to the ureter, in the meso-ureter, and 2 cm superior and parallel to the uterosacral ligament.[2,3] To identify and preserve its fibers, following ureterolysis, the peritoneum is lifted at the level of the pelvic brim and dissection continued superficially, and caudally, until the fibers of the IHN are visualized [Figure 1]. In cases of peritonectomy for superficial peritoneal endometriosis, the nerve can be fully visualized and kept intact, by gently pushing its fibers off the affected peritoneum that will, subsequently, be excised. Having lateralized the IHN, blunt dissection is continued medially to the nerve, until the left uterosacral ligament is identified medially to it. Should the ligament also need to be excised, it can be done safely with minimal risk of injuring the nerve.Figure 1: Fibers of the left inferior hypogastric nerve (green) in relation to the left ureter (yellow) and the posterior peritoneal leaf of the broad ligament (pale blue).http://www.apagemit.com/page/video/show.aspx?num= 1393&kind=2&page=1The total operative time (excision of Douglas pouch peritoneum and right ovarian cystectomy) was 65 min and the estimated blood loss was 20 mL. The patient was discharged home on postoperative day 1 and made an uneventful recovery. At the 3-month follow-up, she was pain-free, with negative imaging. CONCLUSION Identification and preservation of the IHN are feasible and reproducible by following the surgical steps described here. Ethics statement This study was conducted in accordance with the ethical principles outlined in the Declaration of Helsinki and its amendments. The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given her consent for her images and other clinical information to be reported in the journal. The patient understands that name and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Author contributions Conceptualization, GG; Methodology, Software, Validation, AD; Formal Analysis, Investigation, Resources, Data Curation, GG; Writing – Original Draft Preparation, GG, MA, AP; Writing – Review and Editing, GG, AD; Visualization, GG; Supervision, AD; Project Administration, Funding Acquisition. All authors have read and agreed to the final version of the manuscript. Data availability statement Data sharing is not applicable to this article as no datasets were generated or analyzed during the current study. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.