Cochlear implantation in deafblind patients: a systematic review and meta-analysis

In the past, cochlear implantation (CI) was not commonly offered to this population due to concerns about limited auditory rehabilitation outcomes. Recent advancements in CI technology and multidisciplinary rehabilitation have expanded candidacy, but outcomes in deafblind patients remain underexplored. This systematic review and meta-analysis aimed to synthesize available evidence on CI outcomes in deafblind individuals.

Data sources included PubMed, Web of Science, Scopus, and Cochrane Library from inception to July 20, 2025. Observational studies included adults or children with confirmed dual sensory impairment after CI. Primary outcomes included speech clarity (Speech Intelligibility Rating [SIR]), verbal communication ability, and telephone communication competence. Secondary outcomes encompassed audiological performance, auditory and cognitive development, educational integration, psychological benefits, and advanced auditory skills. Risk of bias was examined using the NIH Quality Assessment Tool and Newcastle-Ottawa Scale. STATA 18 was used to perform random-effects meta-analyses.

Thirty-six studies were analyzed, including 491 patients (mean age 23.68 years; 23% male). The pooled mean SIR score was 3.45 (95% CI: 2.69-4.21), with no significant difference between Usher and non-Usher groups (p = 0. 52). Verbal communication ability was achieved in 70% (95% CI: 0.60-0.79), while telephone communication competence was limited to 51% (95% CI: 0.33-0.69).

Cochlear implantation is an effective intervention for deafblind individuals, demonstrating significant improvements in speech intelligibility and verbal communication regardless of the underlying etiology (Usher vs. non-Usher). While verbal communication rates are promising, advanced skills such as telephone competence remain limited, suggesting the need for continued multidisciplinary rehabilitation.