Endoscopic Endonasal V2 Neurectomy at Foramen Rotundum for Intractable Facial Pain

Introduction: Facial pain refractory to conventional medical and surgical treatments is particularly difficult to treat. Neurectomy, in the form of surgical sectioning of the trigeminal nerve’s cisternal portion intracranially or its individual divisions through external incisions, has been reported for treatment of these patients.

Methods: We describe the technique and results of an endonasal endoscopic approach to the maxillary division of the trigeminal nerve at the foramen rotundum for neurectomy and treatment of refractory facial pain in the V2 distribution. Using a unilateral endonasal endoscopic approach (EEA), the foramen rotundum is accessed after ipsilateral maxillary antrostomy, sphenoidotomy and partial removal of the posterior wall of the maxillary sinus for exposure of the pterygopalatine fossa (PPF). Following clip ligation of the sphenopalatine artery, the superior part of the periosteum that covers the PPF is sharply incised toward the pterygoid base. The vidian nerve is identified and the periosteum of the pterygoid base is elevated laterally. This step is important to preserve the structural integrity and functionality of the vidian nerve. Finally the V2 nerve is identified exiting the foramen rotundum, a few millimeters lateral and superior to the vidian nerve. The maxillary nerve is sharply divided, and then cauterized deep within the foramen.

Results: Three patients (1 trigeminal neuralgia, 1 atypical facial pain, and 1 posttraumatic facial pain) with predominantly maxillary division trigeminal distribution pain that had failed other medical and surgical treatments were treated with EEA V2 neurectomy at the foramen rotundum. One patient had an intraoperative cerebrospinal fluid (CSF) leak successfully repaired with a free mucosal graft from the inferior nasal floor without a postoperative CSF fistula. There were no other early complications of treatment. All patients obtained complete pain relief in the early postoperative period with complete anesthesia in the V2 distribution.

Conclusion: EEA to the foramen rotundum for neurectomy at the cranial base appears to be a safe and effective treatment for patients with refractory or atypical V2 facial pain or patients with contraindications to more invasive procedures due to advanced age or medical comorbidities.