Outcomes of Microvascular Decompression for Hemifacial Spasm at the Philippine General Hospital.

Objective: To report the demographics, clinical characteristics, and surgical outcomes after microvascular decompression (MVD) for hemifacial spasm (HFS) in the Philippine General Hospital (PGH). Methods: Between January 2018 to December 2022, the division of Neurosurgery at PGH performed thirty-four MVD operations for Primary HFS. Records were retrospectively reviewed, and pertinent demographic, intra-operative findings, outcomes, and complications were analyzed. Results: The overall success rate is 88.2%, with a median follow-up at 15 months. Repeated measures ANOVA showed that post-op HFS and follow-up HFS grades were significantly lower than pre-op HFS grades (F=17.46, df=33, p<0.0001). HFS average age of symptom onset was early at 38.5 years, 11.8% of which were <30y/o. The M: F ratio was 1:2.4. Thirty out of 34 patients came for MVD surgery as referrals from a social media support group. Ordered logistic regression showed that years before surgery (OR:7.05, z=2.23, p=0.026) and pre-operative pharmacologic treatment (OR:48, z=2.33, p=0.02) increase the HFS grade to the next worse grade. At the same time, hypertension (OR: 0.006, z=-2.54, p=0.011) decreases pre-operative HFS grade to a lower degree. Post-operative complications were facial nerve palsy (29.4% transient and 5.9% permanent), hearing loss (17.6% transient and 5.9% permanent), CSF leak/infection (2.9%), and recurrence (8.8%). Conclusion: MVD at PGH is a viable choice treatment option for Filipino patients with success rates comparable to internationally published studies. Besides improving surgical technique, improvement of referral systems may help make surgery more accessible.