ISON Guidelines for the Diagnosis and Surgical Management of Endometriosis of the Sciatic Nerve and Sacral Plexus

These official ISON Guidelines summarize the current neuropelveological concepts regarding the diagnosis, pathophysiology, differential diagnosis, and surgical management of endometriosis involving the sciatic nerve and sacral plexus. Developed under the auspices of the International Society of Neuropelveology (ISON), the document reflects one of the world’s largest clinical and surgical experiences in pelvic nerve endometriosis, including more than 600 patients treated over more than two decades of neuropelveological practice. The guidelines emphasize the fundamental distinction between sacral plexus endometriosis and isolated intraneural sciatic nerve endometriosis, two entities with major differences in anatomical origin, biological behavior, neurological progression, imaging findings, and surgical implications. The document introduces a neuropelveological classification system and proposes a novel neuropathogenic model for isolated sciatic nerve endometriosis as a primary intraneural neuro-inflammatory and neuro-regenerative disease process. Detailed recommendations are provided for neuropelveological clinical examination, MRI and transvaginal Doppler ultrasound evaluation, neuro-urological assessment, electrophysiological studies, differential diagnosis, surgical indications, laparoscopic nerve decompression, intrafascicular neurolysis, microsurgical nerve-sparing techniques, vascular management, postoperative rehabilitation, and long-term neurological follow-up. Special emphasis is placed on the prevention of irreversible axonal damage and the necessity for highly specialized neuropelveological expertise and reference centers for surgical treatment. These guidelines aim to establish standardized principles for the diagnosis and treatment of pelvic nerve endometriosis and to improve recognition of these frequently overlooked neuropathic disorders among gynecologists, neurosurgeons, neurologists, pain specialists, radiologists, and pelvic surgeons worldwide. Keywords: Neuropelveology; Endometriosis; Sciatic nerve; Sacral plexus; Pelvic neuropathy; Catamenial sciatica; Laparoscopic nerve surgery; Pelvic nerve entrapment; Deep infiltrating endometriosis; Chronic pelvic pain; Pudendal neuralgia; Sacral radiculopathy; Neurofunctional pelvic surgery; LANN technique.