Familial isolated unilateral large vestibular aqueduct syndrome

Large vestibular aqueduct syndrome (LVAS) is one of the most frequent inner ear malformations. It is associated with varying degrees of hearing loss, that may be progressive, sudden or fluctuant; nevertheless normal hearing in cases with LVAS has been described. Although unilateral LVAS has been described, all patients show clinical and radiological findings in both ears, in contrast to the family presented here, where 2 siblings are affected by unilateral sensorineural hearing loss associated with ipsilateral LVAS, with an autosomal recessive pattern. In order to search for the origin of this inner ear malformation, mutations in genes GJB2 (connexin-26 gene), PDS (Pendred's syndrome gene) and mitochondrial 12sRNA were studied, without positive results. In this paper we hypothesize the probable embryological origin for this malformation.