Type of disease: Rare conditions
Mondini dysplasia is a type of inner ear malformation that is present at birth (congenital). Individuals with Mondini dysplasia have one and a half coils of the cochlea instead of the normal two coils. It may occur in one ear (unilateral) or both ears (bilateral) and can cause varying degrees of sensorineural hearing loss, although most individuals have profound hearing loss. The condition can also predispose affected individuals to recurrent meningitis. It is caused by disruption in the embryonic development of the inner ear during the seventh week of gestation. The condition may be isolated (occurring with no other conditions or malformations) or may occur with other ear malformations or a number of syndromes. Treatment options may include surgical repair of the defect to prevent recurrent meningitis; amplification aids for those with residual hearing; and cochlear implantation. Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.