Outcomes after Microvascular Decompression for Hemifacial Spasm without Definite Radiological Neurovascular...

Area of Science:

• Neurosurgery
• Neurology
• Medical Imaging

Background:

• Hemifacial spasm (HFS) is often attributed to neurovascular compression (NVC) of the facial nerve.
• Preoperative MRI is standard for identifying NVC, but cases without clear radiological findings exist.

Purpose of the Study:

• To evaluate the efficacy of microvascular decompression (MVD) in patients diagnosed with hemifacial spasm (HFS) who lack definitive radiological evidence of neurovascular compression (NVC) on MRI.
• To analyze the intraoperative findings, including the types of compressing vessels, compression sites, and patterns in these specific HFS cases.

Main Methods:

• Retrospective analysis of 16 hemifacial spasm (HFS) patients who underwent microvascular decompression (MVD) surgery.
• Patients selected had no definite neurovascular compression (NVC) identified on preoperative MRI.
• Intraoperative findings regarding vessel compression, location, and type were meticulously recorded.

Main Results:

• All 16 patients (100%) experienced symptom improvement following MVD surgery.
• The anterior inferior cerebellar artery (AICA) was the most frequent culprit vessel (44.4%).
• Compression predominantly occurred at the cisternal portion (76.5%) of the facial nerve, with arachnoid type being the most common pattern (50%).

Conclusions:

• Microvascular decompression (MVD) surgery is a viable and effective treatment for primary hemifacial spasm (HFS) even when preoperative MRI does not reveal definitive neurovascular compression (NVC).
• MVD should be considered for patients presenting with typical HFS symptoms, irrespective of MRI findings, as intraoperative exploration may reveal causative NVC.