[The study of hearing loss after microvascular decompression for hemifacial spasm].

Objective: To compare the difference of hearing loss after microvascular decompression for hemifacial spasm between control and experimental groups, and to explore the possible causes. Methods: A retrospective analysis including 443 patients was performed, including 203 cases of group A (before the operation was improved) and 240 cases of group B (after the operation was improved). Chi-square test was used to compare the rate of hearing loss. Results: There were 18(8.9%) cases with postoperative hearing loss in group A, including 9 cases of conductive hearing loss and 9 cases of sensorineural hearing loss.While 2 cases of conductive hearing loss and 3 cases of sensorineural hearing loss occurred in group B. Conductive hearing loss and sensorineural hearing loss of two groups had the significant deference (P=0.015 and P=0.04). Conclusion: The type of hearing loss after microvascular decompression for hemifacial spasm included conductive and sensorineural hearing loss.It could be reduced by early closing of the mastoid air chamber, avoiding continuous traction of the cerebellum, avoiding excessive irrigation and exhaust, and intraoperative auditory brainstem evoked potential monitoring.