title: Variety of audiologic manifestations in patients with superior semicircular canal dehiscence.
abstract: OBJECTIVE
  To present diverse symptoms, signs, and findings on diagnostic tests of 11 patients with superior semicircular canal dehiscence (SSCD) syndrome and surgical treatments for dehiscence of 3 patients.
  
  
  METHODS
  Retrospective case review.
  
  
  METHODS
  Tertiary neurotologic and audiologic center.
  
  
  METHODS
  Patients with SSCD documented by history, physical examination, vestibular function testing, and high-resolution computed tomographic scans.
  
  
  METHODS
  Two patients underwent surgical procedures through middle fossa approach, and 1 patient underwent transmastoid repair. The rest underwent conservative treatments.
  
  
  RESULTS
  Eleven patients were identified as SSCD. The variety of clinical manifestations, including 1) hearing presentations: mix hearing loss (4 of 11), conductive hearing loss (3 of 11), profound sensorineural hearing loss (2 of 11), and normal hearing (2 of 11); 2) vestibular manifestations: chronic disequilibrium (8 of 11), Tullio phenomenon (7 of 11), Hennebert sign (8 of 11), tinnitus (3 of 11), and autophony (3 of 11); and 3) accompanying disorders: encephalomeningocele (1 of 11). Abnormal nystagmus was identified in 3 patients. Dehiscence of bone overlying superior semicircular canal was confirmed by high-resolution computed tomographic scan in all cases. Three patients underwent operative management. (2 through the middle fossa approach and 1 through a transmastoid repair).
  
  
  CONCLUSIONS
  Superior semicircular canal dehiscence demonstrates diverse and complex clinical features. Tegmental or petrosal bone rarefaction or mild dehiscences can be a harbinger or an aggressive cause of developing SSCD. No correlation was observed between the size of dehiscence and the severity of vestibular symptoms or the degree of hearing loss. Surgical repair of dehiscence can relieve symptoms with low morbidity.
authors.affiliation: Department of Otology & Skull Base Surgery, Eye and ENT Hospital, Fudan University, Shanghai, People's Republic of China. chifanglu@yahoo.com.cn
authors.forename: Fang-Lu
authors.initials: FL
authors.lastname: Chi
authors.forename: Dong-Dong
authors.initials: DD
authors.lastname: Ren
authors.forename: Chun-Fu
authors.initials: CF
authors.lastname: Dai
mesh_terms: D000328:Adult; D000368:Aged; D001299:Audiometry; D001844:Bone Conduction / Q000502:physiology; D005260:Female; D006314:Hearing Loss, Conductive / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012189:Retrospective Studies; D012665:Semicircular Canals / Q000002:abnormalities* / Q000503:physiopathology / Q000601:surgery; D013577:Syndrome; D013701:Temporal Bone / Q000000981:diagnostic imaging / Q000601:surgery; D014012:Tinnitus / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology / Q000601:surgery; D015837:Vestibular Diseases / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D014724:Vestibular Function Tests