title: Absent semicircular canals in CHARGE syndrome: radiologic spectrum of findings.
abstract: OBJECTIVE
  This paper describes the CT findings that characterize the middle and inner ear anomalies in coloboma, heart defects, choanal atresia, mental retardation, genitourinary, and ear anomalies (CHARGE) syndrome. With this information, neuroradiologists will be better prepared to provide clinically relevant information to their referring physicians regarding this rare syndrome.
  
  
  METHODS
  CT studies from 13 patients were reviewed by 2 neuroradiologists with Certificate of Additional Qualification. Each ear was counted separately for a total of 26 ears. Middle and inner ear anomalies associated with CHARGE syndrome were categorized. Investigational review board approval was obtained.
  
  
  RESULTS
  Twenty of 26 (77%) ears demonstrated cochlear aperture atresia. Four of these ears were evaluated with MR imaging and were found to lack a cochlear nerve. Twenty-one of 26 (81%) cochlea had some form of dysplasia. Six of 26 (23%) round windows were aplastic. Three of 26 (12%) round windows were hypoplastic. Twenty-one of 26 (81%) oval windows were atretic or aplastic. Fifteen of 26 (58%) vestibules were hypoplastic or dysplastic. There were 5 of 26 (19%) enlarged vestibular aqueducts. Twelve of 26 (46%) vestibular aqueducts had an anomalous course. All cases demonstrated absent semicircular canals. Twenty-three of 26 (88%) facial nerve canals had an anomalous course. Four of 26 (15%) tympanic segments were prolapsed. Three of 26 (12%) temporal bones had an anomalous emissary vein referred to as a petrosquamosal sinus. Twenty-one of 26 (81%) middle ear cavities were small. Twenty-three of 26 (93%) ossicles were dysplastic with ankylosis. Three of 26 (12%) internal auditory canals were small.
  
  
  CONCLUSIONS
  The CT findings that correlate to the anomalies of CHARGE syndrome affect conductive as well as sensorineural hearing. Stenosis of the aperture for the cochlear nerve aperture on CT is suggestive of hypoplasia or absence of the cochlear nerve, which has been demonstrated in some cases by MR. Absence of the cochlear nerve would be a contraindication to cochlear implantation.
authors.affiliation: Department of Radiology, University of Utah Health Sciences Center, Salt Lake City, Utah 84132, USA. alan.morimoto@hsc.utah.edu
authors.forename: A K
authors.initials: AK
authors.lastname: Morimoto
authors.forename: R H
authors.initials: RH
authors.lastname: Wiggins
authors.forename: P A
authors.initials: PA
authors.lastname: Hudgins
authors.forename: G L
authors.initials: GL
authors.lastname: Hedlund
authors.forename: B
authors.initials: B
authors.lastname: Hamilton
authors.forename: S K
authors.initials: SK
authors.lastname: Mukherji
authors.forename: S A
authors.initials: SA
authors.lastname: Telian
authors.forename: H R
authors.initials: HR
authors.lastname: Harnsberger
mesh_terms: D000015:Abnormalities, Multiple / Q000000981:diagnostic imaging*; D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D002754:Choanal Atresia / Q000000981:diagnostic imaging; D003103:Coloboma / Q000000981:diagnostic imaging; D007758:Ear, Inner / Q000002:abnormalities / Q000000981:diagnostic imaging; D004432:Ear, Middle / Q000002:abnormalities / Q000000981:diagnostic imaging; D005260:Female; D006314:Hearing Loss, Conductive / Q000175:diagnosis; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis; D006330:Heart Defects, Congenital / Q000000981:diagnostic imaging; D006801:Humans; D007223:Infant; D008607:Intellectual Disability / Q000000981:diagnostic imaging; D008297:Male; D011859:Radiography; D012189:Retrospective Studies; D012665:Semicircular Canals / Q000002:abnormalities* / Q000000981:diagnostic imaging; D012680:Sensitivity and Specificity; D013577:Syndrome; D015898:Tomography Scanners, X-Ray Computed; D014564:Urogenital Abnormalities / Q000000981:diagnostic imaging