Background: Long-term assessments of children with cochlear implants (CI) are important inputs
to help guide families and professionals in therapeutic and counselling processes. Based on these
premises, the primary aim of the present study was to assess the long-term speech and language
outcomes in a sample of prelingually deaf or hard of hearing (DHH) adolescents and young adults
with unilateral or bilateral implantation in childhood. The secondary aim was to investigate the
correlations of age at implantation with long-term speech and language outcomes.
Materials and Methods: Retrospective observational study on 54 long-term CI users, 33 unilateral
and 21 bilateral (mean age at CI surgery 38.1 ± 24.6 months; mean age at last follow-up assessment
19.1 ± 4.3 years of age and mean follow-up time 16 ± 3.7 years). Means and standards were used to
describe speech perception (in quiet, in fixed noise and in adaptive noise using It-Matrix) and
morphosyntactic comprehension (TROG-2) outcomes. A univariate analysis was used to evaluate
outcome differences between unilateral and bilateral patients. Bivariate analysis was performed to
investigate the relationships between age at CI, audiological variables, and language outcomes.
Finally, multivariate analysis was performed to quantify the relationship between It-Matrix,
sentence recognition in quiet and at SNR+10 and TROG-2.
Results: The participants showed good speech recognition performance in quiet (94% for words
and 89% for sentences) whilst their speech-in-noise scores decreased significantly. For the It-
Matrix, only 9.2% of the participants showed scores within the normative range. This value was
60% for TROG-2 performance. For both auditory and language skills, group differences for
unilateral versus bilateral CI users were not statistically significant (p >0.05). Bivariate analysis
showed that age at CI correlated significantly with overall results at TROG-2 (r = -0.6; p <0.001)
and with It-Matrix (r =0.5; p <0.001). TROG-2 was negatively correlated with results for It-Matrix
(r = -0.5; p <0.001). In the multivariate analysis with It-Matrix as a dependent variable, the model
explained 63% of the variance, of which 60% was related to sentence recognition and 3% to
morphosyntax.
Conclusions: These data contribute to the definition of average long-term outcomes expected in
subjects implanted during childhood whilst increasing our knowledge of the effects of variables
such as age at CI and morphosyntactic comprehension on speech perception. Although the majority
of this prelingually DHH cohort did not achieve scores within a normative range, remarkably better
It-Matrix scores were observed when compared to those from postlingually deafened adult CI users