title: Bilateral versus unilateral sudden sensorineural hearing loss.
abstract: OBJECTIVE
  To analyze the clinical characteristics and treatment results between bilateral (bi-) and unilateral (uni-) sudden sensorineural hearing loss (SSNHL).
  
  
  METHODS
  A retrospective study.
  
  
  METHODS
  Three hundred twenty-four patients with SSNHL were classified into two groups; simultaneous bi-SSNHL (n = 16) and uni-SSNHL (n = 308). We compared clinical characteristics, medical history, hearing level, and treatment results between the 2 groups.
  
  
  RESULTS
  The incidence of bi-SSNHL was 4.9 percent of overall patients with SSNHL. Bi-SSNHL occurs more commonly in patients of older age, with preexisting diabetes mellitus, and lipid panel abnormalities compared with uni-SSNHL. Ten patients (62.5%) in the bi-SSNHL group showed hearing recovery in 1 or both ears compared with 56.5 percent of patients with uni-SSNHL. Only 12 (37.5%) of all 32 ears recovered in bi-SSNHL, which was significantly lower than in uni-SSNHL.
  
  
  CONCLUSIONS
  Bi-SSNHL has a very low incidence and lower recovery rate than uni-SSNHL. Recognition of similarities and differences between bilateral and unilateral SSNHL can help in counseling and managing the patients.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, the Catholic University of Korea, College of Medicine, Seoul, Korea.
authors.forename: Jeong-Hoon
authors.initials: JH
authors.lastname: Oh
authors.forename: Keehyun
authors.initials: K
authors.lastname: Park
authors.forename: Seung Joo
authors.initials: SJ
authors.lastname: Lee
authors.forename: You Ree
authors.initials: YR
authors.lastname: Shin
authors.forename: Yun-Hoon
authors.initials: YH
authors.lastname: Choung
mesh_terms: D015897:Comorbidity; D003920:Diabetes Mellitus / Q000453:epidemiology; D005260:Female; D006309:Hearing; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology / Q000503:physiopathology; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D020127:Recovery of Function; D012189:Retrospective Studies