title: Bony cochlear nerve canal stenosis and speech discrimination in pediatric unilateral hearing loss.
abstract: OBJECTIVE
  To examine the relationship between bony cochlear nerve canal (BCNC) width, degree of hearing loss, and speech discrimination in children with unilateral sensorineural hearing loss (USNHL).
  
  
  METHODS
  Retrospective chart review (case-control study).
  
  
  METHODS
  Audiometric database was cross-referenced with radiologic database at pediatric tertiary care facility to identify children with USNHL and temporal bone computed tomography. BCNC widths were measured independently by two radiologists blinded to affected ear. Regression analyses investigated associations among variables.
  
  
  RESULTS
  One hundred and sixty children with USNHL had temporal bone imaging. Mean BCNC width was significantly smaller in affected ears, P = 0.0001. Narrower width was associated with more severe hearing loss, P = 0.01. Among children who had narrower cochlear nerve canals in affected ears compared to unaffected ears, smaller width was associated with lower speech discrimination score, P = 0.03. Increasing asymmetry in BCNC width between affected and unaffected ears was associated with poorer discrimination scores, P = 0.02. Among ears with asymmetrically smaller cochlear nerve canals, a 1-mm reduction in cochlear canal width between the normal and affected ear was associated with 30.4% lower word recognition score percentage in the affected ear, P = < 0.001.
  
  
  CONCLUSIONS
  There is a significant association between BCNC stenosis and impaired speech discrimination, independent of degree of hearing loss. Further investigation is needed to determine whether BCNC stenosis is a poor prognostic factor for auditory rehabilitation.
authors: Department of Otolaryngology, University Of Washington, Seattle, Washington.
authors: Patricia L
authors: PL
authors: Purcell
authors: Department of Otolaryngology, Henry Ford Health System, Detroit, Michigan, U.S.A.
authors: Ayaka J
authors: AJ
authors: Iwata
authors: Department of Radiology, University Of Washington, Seattle, Washington.
authors: Grace S
authors: GS
authors: Phillips
authors: Department of Radiology, University Of Washington, Seattle, Washington.
authors: Angelisa M
authors: AM
authors: Paladin
authors: Department of Otolaryngology, University Of Washington, Seattle, Washington.|Department of Otolaryngology, Seattle Children's Hospital, Seattle, Washington.
authors: Kathleen C Y
authors: KC
authors: Sie
authors: Department of Otolaryngology, University Of Washington, Seattle, Washington.|Department of Speech and Hearing Sciences, University Of Washington, Seattle, Washington.|Department of Otolaryngology, Seattle Children's Hospital, Seattle, Washington.
authors: David L
authors: DL
authors: Horn
mesh_terms: D000293:Adolescent; D001299:Audiometry; D002648:Child; D002675:Child, Preschool; D003056:Cochlear Nerve / Q000503:physiopathology*; D003251:Constriction, Pathologic / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D046088:Hearing Loss, Unilateral / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012189:Retrospective Studies; D013067:Speech Perception; D013701:Temporal Bone / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed; D055815:Young Adult
keywords: Unilateral hearing loss; cochlear nerve deficiency; computed tomography; temporal bone