title: Correlation Between Cerebellar Retraction and Hearing Loss After Microvascular Decompression for Hemifacial Spasm: A Prospective Study.
abstract: BACKGROUND
  This study prospectively investigated the relationship between cerebellar retraction factors measured on preoperative magnetic resonance and the development of postoperative hearing loss and evaluated their potential role in predicting the possibility of hearing loss after microvascular decompression (MVD) for hemifacial spasm (HFS).
  
  
  METHODS
  The study included 110 patients clinically diagnosed with primary HFS who underwent MVD in our department. The cerebellar retraction factors were quantitatively measured on preoperative magnetic resonance. Associations of cerebellar retraction and other risk factors with postoperative hearing loss were analyzed.
  
  
  RESULTS
  Eleven patients (10%) developed nonserviceable hearing loss after MVD. Compared with the group without hearing loss, the cerebellar retraction distance and depth of the group with hearing loss were significantly greater (P < 0.05). Multivariate logistic regression analysis showed that greater cerebellar retraction depth was significantly associated with the higher incidence of postoperative hearing loss (P < 0.05).
  
  
  CONCLUSIONS
  The results in this study strongly suggested the correlation between the cerebellar retraction depth and the possibility of hearing loss after MVD for HFS. In addition, cerebellar retraction depth could be considered as a useful tool to predict the risk of post-MVD hearing loss.
authors.affiliation: Department of Neurosurgery, Rui Jin Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.affiliation: Department of Neurosurgery, Rui Jin Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China. Electronic address: rjneurosurgeon@126.com.
authors.forename: Wei-Guo
authors.initials: WG
authors.lastname: Zhao
authors.affiliation: Department of Neurosurgery, Rui Jin Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China.
authors.forename: Chun-Hua
authors.initials: CH
authors.lastname: Pu
authors.affiliation: Department of Neurosurgery, Rui Jin Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China.
authors.forename: Wen-Lei
authors.initials: WL
authors.lastname: Yang
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D000368:Aged; D001299:Audiometry; D002531:Cerebellum / Q000503:physiopathology*; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology; D005260:Female; D034381:Hearing Loss / Q000000981:diagnostic imaging / Q000209:etiology*; D019569:Hemifacial Spasm / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D021621:Imaging, Three-Dimensional; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008297:Male; D061145:Microvascular Decompression Surgery / Q000009:adverse effects*; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D011183:Postoperative Complications / Q000209:etiology*; D011446:Prospective Studies
keywords: Cerebellar retraction; Hearing loss; Hemifacial spasm; Microvascular decompression; Predictor