Outcomes of cochlear implantations for mumps deafness: A report of four pediatric cases

Single-sided deafness after sudden hearıng loss: late effect on cochlear nerve size

PURPOSE

Single-sided deafness (SSD) is a condition where an individual has non-functional hearing in one ear and receives no clinical benefit from amplification in that ear, with the contralateral ear possessing normal audiometric function. Cochlear implant presents a good choice in rehabilitation of SSD. The presence of a deficient cochlear nerve (CN) has been linked to poor performance with cochlear implants. CN can be measured by imaging techniques. The objective of this study was to compare CN diameter in patients who had a history of single-sided deafness because of sudden hearing loss.

METHODS

Retrospective study where radiologist was blind designed. 53 SSD patients who had a history of sudden hearing loss and MRI at least 5 years after the sudden hearing loss were included in this retrospective study. High-resolution 3-D constructive interference in steady state (CISS)-sequence magnetic resonance (MRI) images was review by the neurotology-experienced blind radiologist. Vertical, horizontal and area measurements of cochlear nerve between the deaf and the normal ear were made.

RESULTS

There was no statistically significant difference between the normal ear and deaf ear of the subjects in terms of cochlear nerve vertical diameter, horizontal diameter and area. (respectively, p = 0.250; p = 0.183; p = 0.874) CONCLUSION: The numbers of remaining cochlear neurons and spiral ganglion cells in the implanted deaf ears are critical and evidence was not found for spiral ganglion cell loss in the sudden hearing loss deaf ear with SSD in MRI. In the light of all these findings, implantation would be a good choice for rehabilitation in postlingual SSD regardless of auditory deprivation duration.

The impact of etiology and duration of deafness on speech perception outcomes in SSD patients

OBJECTIVE

To investigate a cohort of adult single-sided deafness (SSD) patients who received a cochlear implant and to determine the impact of underlying causes of etiology and duration of deafness on outcome STUDY DESIGN: Retrospective data analysis SETTING: Tertiary referral centre with a large cochlear implant program SUBJECTS AND METHODS: A demographic description of 55 adult patients implanted between 2009 and 2016. The best available speech perception score in every patient using the Freiburg Numbers, Freiburg Monosyllables and the Hochmair-Schulz-Moser (HSM) sentence test measured at the 1-, 3-, 6- and 12-month intervals, and the yearly follow-up appointments were examined. A multivariate regression analysis was conducted on the variables speech test, duration of deafness and etiology. Patients were split into four groups according to their duration of deafness (shorter duration of 10 years or less versus longer duration of more than 10 years) and etiology (inflammatory disease versus other causes).

RESULTS

The median word reception score for the Monosyllables at 65 dB SPL were 43.75% (IQR: 29.38) and 67.50% (IQR: 25.63) at 80 dB SPL at 1 year following cochlear implantation. The median percentage score correct for the HSM sentence test was 80% (IQR: 62.95). Etiology of the reviewed patient cohort revealed that most frequent causes for deafness were sudden hearing losses and inflammatory etiologies, e.g. otitis media, labyrinthitis, meningitis, cholesteatoma or mumps. The duration of deafness was not significantly associated with poor speech perception outcome. A significant correlation was found for inflammatory diseases and duration of deafness of longer than 10 years.

CONCLUSION

The etiology and duration of deafness are important factors for the estimated outcome in speech perception in SSD patients. Presented data reveal that an inflammatory disease leading to deafness in combination with a long duration of deafness (10 + years) lead to poorer speech perception outcomes.