The Clinical Significance of eCAP And eSRT in Children Using Cochlear Implant: A Systematic Review

Abstract

Sensorineural hearing impairment affects around 5% of over a million people worldwide, lying into the category of disability with which people live for years. Cochlear Implant (CI) is a neuro-prosthetic device that is viable and has been used as the standard treatment option for individuals with severe-to-profound sensorineural hearing loss. Modern CI devices assist programming by enabling objective metrics like electrically evoked compound action potential (eCAP) and electrically evoked stapedius reflex threshold (eSRT) to be used, to supplement behavioural assessments. In order to begin the mapping process, especially when it comes to infants and young children, objective measures are used in the CI process. These measures provide specific values that serve as the starting point for the mapping process. The present systematic review throws light on the efficiency of the objective measurements used in cochlear implantation. Further, the correlation between the objective and the subjective measures, as a clinical tool in patients with the cochlear implant is also discussed. The review was conducted based on the PRISMA statement, and the data sources used include PubMed/Medline, Google Scholar, and ResearchGate, a List of references, and citations. A systematic search for articles regarding eCAP and eSRT was done between the years 2000-2020 with relevant keywords, and a study population of up to 10 years of age was considered. Out of 4614 articles, there were 8 full-length articles that fulfilled the inclusion criteria defined in the study and were considered for further discussion. Most of the studies investigated either correlation of eCAP or eSRT with behavioural measures. Overall, studies showed a straightforward estimation of the eSRT in comparison to the eCAP thresholds. Further, there is a high correlation reported between eSRT and behavioural thresholds obtained for comfort levels compared to eCAP thresholds. Thus, the present systematic review concludes that eSRT is a reliable tool, if present compared to eCAP for mapping CI in the paediatric population.