Simplified Matrix Sentence Test for Pediatric Cochlear Implant Fitting: Single Institution Experience

Background/Objectives: The Matrix Sentence Test is an audiological evaluation that quantifies the signal-to-noise ratio, expressed in decibels, at which the patient comprehends 50% of the words of a random sentence heard in noise. It is an effective and reliable tool for cochlear implant fitting and follow-up in both adults and children, demonstrating reliability upon repeated administration. A simplified model of the Matrix Sentence Test can be used in children. This study had two main objectives: first, to evaluate the Simplified Matrix Sentence Test for objectively estimating post-fitting CI performance; and second, to assess the influence of various demographic and device-related variables on the results. The variables of interest included gender, manufacturer, placement, microphone position, array position, score in pre-fitting speech audiometry in quiet, age at first implantation, age at test administration, and the interval between the first implant and the test administration. Methods: A retrospective study of pediatric patients with cochlear implants was performed. The inclusion criteria were patients aged 7-18 years, with a minimum of two years of cochlear implantation, adequate Italian language proficiency, and regular follow-up attendance. The subjects were administered the Simplified Matrix Sentence Test prior to and following map fitting by an experienced audiologist. Results: The study's sample population included 51 patients who met the established inclusion criteria, with an average age of 13 years. In the preliminary SiIMax test, the average SNR for 50% sentence comprehension in noise was -0.83 ± 1.86 dB. Map adjustments included reductions or increases in comfort and threshold levels, modifications to multiple electrodes, or minor secondary changes. Approximately two days later, the second Simplified Matrix Sentence Test was administered. The average signal-to-noise for sentence comprehension was -2.05 ± 1.73 dB. Univariate and multivariate analyses revealed that no variable had a statistically significant impact on the results. Conclusions: The Simplified Matrix Sentence Test demonstrated universal applicability in compliant patients. Post-implant improvement appeared independent of patient demographics and device variables.