Cochlear implantation in a 10-year old boy with Pendred syndrome and extremely enlarged endolymphatic sacs.

A 10-year-old boy with fluctuating sensorineural hearing loss (SNHL) and biallelic mutations in the SLC26A4 gene and with inner ear anomalies received a cochlear implantation. SLC26A4 mutations are associated with variable degrees of SNHL and enlarged vestibular aqueducts (EVA), identified either as non-syndromic EVA or classic Pendred syndrome; the latter also associated with thyroid dysfunction. The inner ear malformations in this group of patients have been considered a relative contraindication against cochlear implantation because of the potential per- and postoperative complications such as peroperative cerebrospinal fluid leak or postoperative vestibular symptoms. In the current case there were no surgical or postoperative complications, indicating that extremely enlarged endolymphatic sacs are not as such a contraindication for cochlear implantation. This case also illustrates the management dilemma of an appropriate timing for cochlear implantation.