Surgical Options for Cranial Nerve Functional Diseases

Cranial nerve (CN) functional diseases, comprising trigeminal neuralgia (TN), hemifacial spasm (HFS), and glossopharyngeal neuralgia (GN), are frequently caused by neurovascular conflicts (NVCs) in the posterior fossa. This chapter examines surgical and non-surgical procedures for these conditions, emphasizing minimally invasive retrosigmoid approach (RA) for microvascular decompression (MVD) as the gold standard for definitive treatment for all of them. MVD achieves long-term pain relief in more than 80% of classical TN cases, though efficacy decreases significantly in multiple sclerosis (MS)-related TN. Technical nuances of MVD, such as patient positioning, craniectomy location, and conflict visualization via microscopic, endoscopic, or exoscopic systems, are detailed, alongside strategies to minimize complications (CSF leakage, vascular or nerve injuries). Percutaneous techniques (radiofrequency thermorhizotomy, balloon compression) and stereotactic radiosurgery offer viable alternatives, albeit with variable durability on symptoms control. Special considerations for MS-related TN, tumor-associated cases, and recurrent disease underscore the need for tailored algorithms integrating intraoperative imaging and tools. Advances in endoscopic and exoscopic visualization systems enhance intraoperative precision and ergonomics, though mastery remains technically demanding. A multidisciplinary framework is critical for optimizing outcomes.