Cochlear implantation in chronic demyelinating inflammatory polyneuropathy

Hearing loss in inner ear and systemic autoimmune disease: A systematic review of post-cochlear implantation outcomes

OBJECTIVES

To assess outcomes following cochlear implantation (CI) in patients with hearing loss secondary to primary or secondary autoimmune inner ear disease (AIED).

METHODS

A systematic review and narrative synthesis was completed according to PRISMA guidelines. Databases searched included MEDLINE, PubMed, EMBASE, Web of Science, Cochrane Collection, and ClinicalTrials.gov. No limits were placed on year of publication or language.

RESULTS

A total of 551 studies were identified, of which 29 were included after removal of duplicates, and screening the title, abstract, and full text. All except one study were OCEBM grade IV. 114 of 115 patients displayed improvement in hearing following cochlear implantation. With implant use, roughly a third of these patients had hearing that improved over time, a third improved and plateaued, and a third remained stable. There was no additional risk of perioperative complications found in AIED patients compared what is generally accepted in general cochlear implantation, although two episodes of device failure after 6 months were noted, and four patients with secondary AIED displayed poor initial audiological outcomes.

CONCLUSION

CI in both primary and secondary AIED provides marked improvement in hearing. Early CI may be a valid management option, provide long-lasting hearing in patients and reduce the side effects of long-term systemic immunosuppressants. However, patients should be counseled residual hearing may be lost if there is cochlear ossification or fibrosis which may make implant insertion more traumatic.

LEVEL OF EVIDENCE

NA.

Prelingual Deaf Children Treated With Cochlear Implant: Monitoring Performance With Percentiles

OBJECTIVES

To develop a percentile ranking system driven by speech recognition data obtained from different groups of patients treated with a cochlear implant to serve as a tool to monitor the progress of these patients.

STUDY DESIGN

Prospective study.

SETTING

Tertiary referral center.

PATIENTS

Diagnosed with a bilateral, profound sensorineural hearing loss treated with a unilateral cochlear implant.

INTERVENTION

Diagnostic.

MAIN OUTCOME MEASURE

Six different percentiles (p) were classified taking into account the correlation between speech recognition outcome scores and age at implantation, with reference to the onset of hearing loss.

RESULTS

Four hundred sixteen prelingual patients were included. These subjects were divided into subgroups depending on age at implantation.Prelingual group, from the fifth year after implantation, p50 centered on the following percentages of correct words in each subgroup: 100, 94.6, 91.4, 91.0, 79.2, and 63.1% in children implanted under 12 months, 1, 2, 3, 4 to 6, 7 to 10 years, respectively. After a 12-year follow-up, a significant negative correlation between age at implantation and speech recognition was observed in both prelinguals (Rhos=-0.578, p<0.001).

CONCLUSION

A percentile system was developed to monitor the postimplant progress of prelingual deaf implanted patients, with potential applications in patient follow-up and handling circumstances that may deteriorate results.

Auditory synaptopathy, auditory neuropathy, and cochlear implantation

Cochlear implantation has become the standard-of-care for adults and children with severe to profound hearing loss. There is growing evidence that qualitative as well as quantitative deficits in the auditory nerve may affect cochlear implant (CI) outcomes. Auditory neuropathy spectrum disorder (ANSD) is characterized by dysfunctional transmission of sound from the cochlea to the brain due to defective synaptic function or neural conduction. In this review, we examine the precise mechanisms of genetic lesions causing ANSD and the effect of these lesions on CI outcomes. Reviewed data show that individuals with lesions that primarily affect the cochlear sensory system and the synapse, which are bypassed by the CI, have optimal CI outcomes. Individuals with lesions that affect the auditory nerve show poor performance with CIs, likely because neural transmission of the electrical signal from the CI is affected. We put forth a nuanced molecular classification of ANSD that has implications for preoperative counseling for patients with this disorder prior to cochlear implantation. We propose that description of ANSD patients should be based on the molecular site of lesion typically derived from genetic evaluation (synaptopathy vs. neuropathy) as this has implications for expected CI outcomes. Improvements in our understanding of genetic site of lesions and their effects on CI function should lead to better CI outcomes, not just for individuals with auditory neuropathy, but all individuals with hearing loss.

Conductive hearing loss in chronic inflammatory demyelinating polyneuropathy (CIDP): A case report

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a progressive autoimmune disorder that targets peripheral nerves. It commonly presents with motor-predominant dysfunction and enlargement of cranial nerves. With regards to hearing loss, a few cases of sensorineural loss have been described. We present a novel case of conductive hearing loss caused by a mass on the tympanic segment of the facial nerve in the setting of CIDP.