[Neurovascular interactions in hemifacial spasm]

Area of Science:

• Neurosurgery
• Neurology
• Microsurgery

Context:

• Hemifacial spasm (HS) is a neurological disorder characterized by involuntary contractions of facial muscles.
• Compression of the facial nerve root exit zone (REZ) by aberrant blood vessels is a primary cause of HS.
• Understanding the morphology of the facial nerve REZ is crucial for surgical planning.

Purpose:

• To evaluate the surgical treatment outcomes for 37 patients with hemifacial spasm (HS).
• To correlate morphological findings of the facial nerve REZ with intraoperative observations.
• To assess the efficacy and safety of vascular decompression surgery for HS.

Summary:

• Surgical treatment involved 37 patients with HS, with morphological studies revealing a central myelinated zone extension of 0.9-3.6 mm at the facial nerve REZ.
• Intraoperative findings indicated vascular compression in all cases, with the anterior inferior cerebellar artery (AICA) being the most common culprit.
• Complete decompression was achieved in 35 patients, leading to excellent surgical outcomes in 33 cases with no serious postoperative complications.

Impact:

• Vascular decompression is a highly effective and safe procedure for treating hemifacial spasm.
• The study supports the hypothesis that HS results from compression of the facial nerve's central myelinated zone.
• Surgical decompression should be performed precisely at the brainstem REZ to address the underlying pathology of HS.