Computed tomographic findings of X-linked deafness: a spectrum from child to mother, from young to old, from boy to girl, from mixed to sudden hearing loss.

PURPOSE

Congenital mixed hearing loss associated with fixed stapes footplate is a rare disorder transmitted through X-linked inheritance. The purpose of this study was to report the radiologic findings of X-linked deafness with middle ear anomalies in affected children and young patients and in carrier women.

MATERIALS AND METHODS

The computed tomographic and audiometric findings of 7 subjects (4 affected children and young patients, 1 of whom is a girl; 2 carrier mothers; and a man who presented with sudden hearing loss) from different families were analyzed.

RESULTS

Computed tomography showed bulbous dilatation of the fundi of the internal auditory canals, incomplete bony separation between the basal turn of the cochleas and the lateral ends of the internal auditory canal, deficiency of the modiolus, enlarged first part of the facial nerve, and dilatation of the superior and the inferior vestibular nerve canal and the singular canal. Besides these characteristic findings, dilatation of the vestibular aqueduct was seen except in the man. Middle ear anomalies including oval and/or round window and/or stapes abnormalities were also detected in three affected patients. The carrier mothers had milder forms of some characteristic findings.

CONCLUSIONS

Because of the risks of stapes surgery in X-linked deafness, recognition of the characteristic imaging features of these disorders is important. Especially in young patients with mixed hearing loss, temporal bone computed tomography should be performed before stapes surgery to avoid the complication of stapes gusher. Middle ear anomalies might be highly associated with X-linked deafness.