mr of th e normal and abnormal internal auditory canal

Mr of th e normal and abnormal internal auditory canal update#
Mr of th e normal and abnormal internal auditory canal windows#

Dysplasia was noted if the ossicles demonstrated abnormal morphology or size. The middle ear ossicles were evaluated for dysplasia and/or fusion.

Atresia of the oval and/or round window was identified when they were obscured partly or completely by an osseous septum. The criterion for large vestibular aqueduct was based on a diameter greater than 2 mm in the intraosseous portion. Cochlear aperture was also recorded as normal if patent, visible on an MR when available, or trapped if there was a bony bar over the aperture. Cochlear anomalies were related to presence and size of the basal and apical turns. 13Ĭriteria for evaluation were as follows: aplasia of the semicircular canals was noted when the canals were completely absent and an isolated vestibule was present.

Mr of th e normal and abnormal internal auditory canal update#

A more recent proposed update to the criteria has also been published by Verloes. An updated version of the diagnostic criteria has been published by Blake and is presented in Table 1. Classical diagnostic criteria described by Pagon et al 3 in 1981 include: (1) 1 major feature (coloboma/microphthalmia or choanal atresia), and (2) 4 of the 6 features designated in the CHARGE acronym. 3 Additional anomalies have been reported, including facial palsy or asymmetry, esophageal and laryngeal abnormalities, renal malformations, and facial clefts. 1, 2 CHARGE is an acronym for a complex constellation of anomalies: coloboma, heart defects, choanal atresia, mental retardation, genitourinary hypoplasia, and ear defects. Absence of the cochlear nerve would be a contraindication to cochlear implantation.ĬHARGE syndrome was first described independently by Hall and Hittner et al in 1979. 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. Three of 26 (12%) internal auditory canals were small.ĬONCLUSION: The CT findings that correlate to the anomalies of CHARGE syndrome affect conductive as well as sensorineural hearing. Twenty-three of 26 (93%) ossicles were dysplastic with ankylosis. Twenty-one of 26 (81%) middle ear cavities were small. Three of 26 (12%) temporal bones had an anomalous emissary vein referred to as a petrosquamosal sinus. Four of 26 (15%) tympanic segments were prolapsed. Twenty-three of 26 (88%) facial nerve canals had an anomalous course. All cases demonstrated absent semicircular canals. Twelve of 26 (46%) vestibular aqueducts had an anomalous course. There were 5 of 26 (19%) enlarged vestibular aqueducts. Fifteen of 26 (58%) vestibules were hypoplastic or dysplastic.

Mr of th e normal and abnormal internal auditory canal windows#

Twenty-one of 26 (81%) oval windows were atretic or aplastic.

Three of 26 (12%) round windows were hypoplastic. Six of 26 (23%) round windows were aplastic.

Twenty-one of 26 (81%) cochlea had some form of dysplasia. Four of these ears were evaluated with MR imaging and were found to lack a cochlear nerve. RESULTS: Twenty of 26 (77%) ears demonstrated cochlear aperture atresia. Investigational review board approval was obtained. Middle and inner ear anomalies associated with CHARGE syndrome were categorized. Each ear was counted separately for a total of 26 ears. MATERIALS AND METHODS: CT studies from 13 patients were reviewed by 2 neuroradiologists with Certificate of Additional Qualification. With this information, neuroradiologists will be better prepared to provide clinically relevant information to their referring physicians regarding this rare syndrome. BACKGROUND AND PURPOSE: 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.