Recent understanding of the significance of unilateral hearing loss in children for language development calls for extensive investigations and early rehabilitation. This retrospective study of 90 children with unilateral hearing loss with high resolution CT scans and MRI revealed that nearly half of these subjects had more than one cochlear abnormality. Attention was focused on the cochlear nerve which was aplastic (27.8% cases) or hypoplastic (17.8% cases). The internal auditory canal was narrow in 54.4% cases. Of the 90 subjects, 38 had an atretic or stenotic cochlear aperture which was strongly related to cochlear nerve abnormalities. Narrow IAM was associated with hypoplastic cochlear nerve (32.7%) and the study also found relationships between individual abnormalities. Compared to other similar studies, enlarged vestibular aqueduct was not a major feature here (2.2% cases). Unlike several past studies, this one emphasises the significance of combining MRI with CT imaging because without the former, cochlear implantation would be contraindicated in subjects with cochlear nerve problems, and other avenues such as CROS and BAHA may be helpful.
Role of imaging in unilateral sensorineural hearing loss
Reviewed by Madhup K Chaurasia
Inner-ear malformations as a cause of single sided deafness.
Madhup K Chaurasia
United Lincolnshire Hospitals NHS Trust; University of Leicester, UK.View Full Profile