Cochlear implantation in adolescents with prelinguistic deafness

The aims of this study were to examine auditory function in a group of adolescents with prelingual deafness who received cochlear implants (CI) and to identify poor-outcome predictors in order to define reliable prognostic indicators useful in selecting patients for CI.

Prospective study.

The study was conducted in the Audiology Unit of Cà Granda Ospedale Maggiore Policlinico, Milan, Italy.

The study involved 45 adolescents (mean age at implantation: 13.4 +/- 2.6 years, range: 11-18) with profound congenital hearing impairment with a follow-up of three years. Preimplantation and postimplantation auditory performance and speech perception were evaluated using the mean score of three hearing and speech perception tests (vowel-consonant-vowel [VCV], identification of disyllabic words, and recognition of short sentences) performed in auditory-only listening conditions.

Significant improvements in all speech perception tests were observed after CI. However, 15 cases were considered "poor performers" (i.e., the auditory performance of these patients was less than 30 percent). The diagnosis of deafness in these subjects was significantly delayed (18.07 +/- 6.25 and 34.4 +/- 10.26 months in good and poor performers, respectively, P = 0.006), and their hearing threshold was significantly lower than in the good users group. The mean age at CI was 12.8 +/- 2.33 and 14.53 +/- 2.70 years in good and poor performers, respectively (P = ns).

CI was shown to be a useful device with the ability to reverse the adverse consequences of hearing loss, particularly for prelingual adolescents who receive implantation early in life and who present a hearing threshold of 100 dB or better both at diagnosis and at surgery.