Factors Related to Hemifacial Spasm Recurrence in Patients Undergoing Microvascular Decompression-A Systematic Review and Meta-Analysis

There is a lack of knowledge about the factors associated with the recurrence of hemifacial spam (HFS) following an initially successful microvascular decompression (MVD) surgery. The aim of the present study was to systematically review the pertinent literature and carry out a meta-analysis of factors linked to HFS recurrence in patients undergoing initially successful MVD treatment. An online literature search was launched on the PubMed/Medline and Scopus databases. The following data were collected: sex, age at surgery, affected side, reported improvement after surgery, presence of post-operatory facial weakness, symptom duration, offender vessels, and data obtained from intraoperative neurophysiological monitoring. Upon full-text review, eight articles were included, studying 1105 patients, of which 64 (5.7%) reported recurrence after MVD surgery for hemifacial spasm. There was a statistically significant increased incidence of HFS recurrence in patients with the persistence of lateral spread response (LSR after surgery (OR 9.44 (95% CI 1.69-52.58) p 0.01), while those patients experiencing a shorter disease duration before going to surgery were significantly less prone to experiencing disease recurrence (OR 0.11 (95% CI 0.03-0.46) p 0.002). The remaining examined factors did not result as significantly associated with the risk of recurrence. The funnel plots were largely symmetrical for each variable studied. Taken together, the results of our meta-analysis seem to suggest that short-term symptom duration is a protective factor against HFS recurrence after MVD surgery, while LSR persistence is a negative prognostic factor. Well-designed randomized controlled clinical trials with a long follow-up are expected to further explore therapeutic alternatives for HFS recurrence.

Automated summary

This study systematically reviewed the literature and conducted a meta-analysis to identify factors associated with the recurrence of HFS after initially successful MVD surgery. The findings suggest that the persistence of lateral spread response (LSR) after surgery is significantly associated with an increased risk of HFS recurrence, while a shorter disease duration before surgery is associated with a lower risk of recurrence. Other examined factors did not show a significant association with recurrence risk. These results highlight the importance of short-term symptom duration and LSR persistence as prognostic factors for HFS recurrence after MVD surgery.