title: Delayed restoration of maximum speech discrimination scores in patients with idiopathic sudden sensorineural hearing loss.
abstract: OBJECTIVE
  To assess possible delayed recovery of the maximum speech discrimination score (SDS) when the audiometric threshold ceases to change.
  
  
  METHODS
  We retrospectively examined 20 patients with idiopathic sudden sensorineural hearing loss (ISSNHL) (gender: 9 males and 11 females, age: 24-71 years). The findings of pure-tone average (PTA), maximum SDS, auditory brainstem responses (ABRs), and tinnitus handicap inventory (THI) were compared among the three periods of 1-3 months, 6-8 months, and 11-13 months after ISSNHL onset.
  
  
  RESULTS
  No significant differences were noted in PTA, whereas an increase of greater than or equal to 10% in maximum SDS was recognized in 9 patients (45%) from the period of 1-3 months to the period of 11-13 months. Four of the 9 patients showed 20% or more recovery of maximum SDS. No significant differences were observed in the interpeak latency difference between waves I and V and the interaural latency difference of wave V in ABRs, whereas an improvement in the THI grade was recognized in 11 patients (55%) from the period of 1-3 months to the period of 11-13 months.
  
  
  CONCLUSIONS
  The present study suggested the incidence of maximum SDS restoration over 1 year after ISSNHL onset. These findings may be because of the effects of auditory plasticity via the central auditory pathway.
authors.affiliation: Department of Otolaryngology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan; Department of Hearing Implant Sciences, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan. Electronic address: noguchi.oto@gmail.com.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Noguchi
authors.affiliation: Department of Otolaryngology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.
authors.forename: Masatoki
authors.initials: M
authors.lastname: Takahashi
authors.affiliation: Department of Otolaryngology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.
authors.forename: Taku
authors.initials: T
authors.lastname: Ito
authors.affiliation: Department of Otolaryngology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.
authors.forename: Taro
authors.initials: T
authors.lastname: Fujikawa
authors.affiliation: Department of Otolaryngology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Kawashima
authors.affiliation: Department of Otolaryngology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Kitamura
mesh_terms: D000255:Adenosine Triphosphate / Q000627:therapeutic use; D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D001301:Audiometry, Pure-Tone; D003907:Dexamethasone / Q000627:therapeutic use; D016057:Evoked Potentials, Auditory, Brain Stem; D005260:Female; D003639:Hearing Loss, Sudden / Q000503:physiopathology* / Q000628:therapy; D006801:Humans; D006931:Hyperbaric Oxygenation; D000069555:Injection, Intratympanic; D008297:Male; D008875:Middle Aged; D020127:Recovery of Function; D012189:Retrospective Studies; D013063:Speech Discrimination Tests; D013067:Speech Perception; D011795:Surveys and Questionnaires; D013997:Time Factors; D014012:Tinnitus / Q000503:physiopathology*; D014805:Vitamin B 12 / Q000627:therapeutic use; D014803:Vitamin B Complex / Q000627:therapeutic use; D055815:Young Adult
chemical_list: D000305:Adrenal Cortex Hormones; D014803:Vitamin B Complex; D003907:Dexamethasone; D000255:Adenosine Triphosphate; D014805:Vitamin B 12
keywords: Auditory brainstem response; Deafness; Pure-tone average; Sudden hearing loss; Tinnitus handicap inventory; Word recognition score