2014 Volume 57 Issue 2 Pages 135-142
We report the case of a 6 y/o Japanese-speaking girl whose genetic diagnosis of deafness was useful to select an earlier intervention, including the electric-acoustic stimulation (EAS) operation. Her preoperative pure-tone audiogram showed residual hearing in the lower frequencies bilaterally. Audiological assessment with HA using the monosyllable test showed values of 5% in the right ear and 25% in the left ear. Genetic testing of the blood showed that she had a mitochondrial mutation, suggesting potentially progressive deterioration of the deafness. Her parents provided consent for an EAS-type cochlear implantation using PULSAR FLEX24 via the RW membrane in the right ear. Postoperative assessment after 7 months revealed a result of 100% in the word test for infants and a result of 90% in the test for school children in her right EAS. After 17 months, the mean deterioration threshold of the residual hearing in the low frequencies (125, 250, 500Hz) was only 6.8dB and the residual hearing in the low frequencies was preserved, reflecting the useful effects of EAS. This proved the safety of the EAS-type cochlear implantation in this case.
In conclusion, genetic screening and molecular confirmation seem important to guide the treatment strategy, even in children who have passed the NHS. Proof of genetic mutation encourages parents to receive earlier interventions, including EAS. Furthermore, it also contributes to selection of the optimum electrode length.