Cochlear Implant Outcomes in Patients With Otosclerosis: A Systematic Review

Abstract

ObjectiveThis study aimed to establish hearing outcomes after cochlear implantation in patients with otosclerosis.Materials and MethodsWe conducted a systematic review and narrative synthesis. Databases searched were as follows: MEDLINE, PubMed, Embase, Web of Science, Cochrane Collection, and ClinicalTrials.gov. No limits were placed on language or year of publication. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.ResultsSearches identified 474 abstracts and 180 full texts, with 68 studies meeting the inclusion criteria and reporting outcomes in a minimum of 481 patients with at least 516 implants. Patient-reported outcome measures (PROMs) were reported in five studies involving 51 patients. Intraoperative adverse events/surgical approach details and preoperative radiological assessment were reported in 46 and 38 studies, respectively. The methodological quality of included studies was modest, predominantly consisting of case reports and noncontrolled case series with small numbers of patients. Most studies were Oxford Centre for Evidence Based Medicine grade IV.DiscussionAccess to good rehabilitation support is essential to achieving the good hearing outcomes and PROMs that can be expected by 12 months after implantation in most cases. There was a significant association between the radiological severity of otosclerosis and an increase in surgical and postoperative complications. Postoperative facial nerve stimulation can occur and may require deactivation of electrodes and subsequent hearing detriment.ConclusionsHearing outcomes are typically good, but patients should be counseled on associated surgical complications that may compromise hearing. Modern diagnostic techniques may help to identify potentially difficult cases to aid operative planning and patient counseling. Further work is needed to characterize PROMs in this population.

A full-head model to investigate intra and extracochlear electric fields in cochlear implant stimulation

“…In case of refractory FNS, surgical removal of the CI may be necessary (Smullen et al 2005, Sefien andHamada 2019). Although a previous systematic review and meta-analysis reported a low overall FNS rate of around 5% (Van Horn et al 2020), some subjects exhibit a higher risk of developing this condition depending on the underlying cochlear pathology and anatomy; for instance, otosclerosis may modify the density and therefore the resistivity of the bone tissue, which affect the magnitude and extent of EF patterns through the cochlea and nearby tissue structures (Vanpoucke et al 2004, Seyyedi et al 2013, Burmeister et al 2017, Burck et al 2022, Lam et al 2022. In addition to MP, other stimulation modes, such as bipolar (BP), tripolar (TP), and partial TP (pTP), which aim to improve the focality of the EF over the targeted auditory nerve fibres by reducing current spread, have also been suggested to help alleviate FNS (van der Westhuizen et al 2022, Eitutis et al 2022a.…”