Calibrated Ling Sounds Test for Cochlear Implant fitting in children.

The Implanted children audiometric evaluation inaccuracies may lead to an extended period of the time to achieve proper cochlear implant (CI) electric stimulation. In this work we hypothesized that the relationship between implanted patient hearing thresholds estimation based on the Electrical Cochlear Response (ECR) and detection thresholds to Ling Sounds intensity calibrated according to higher energy spectral component allow electrical current stimulation adjustment of intracochlear electrodes. ECR is an objective test which is performed while patient is asleep and using the CI in everyday operation mode. Stimulus are variable intensity pip tones whose frequency is coincident with the central frequency of the band frequencies in which incoming sound is divided. The ECR Hearing Threshold is determinate by initial ECR detection and is defined as the minimum intensity level which auditory nerve portion involved with test electrode responds to electric stimulation hence producing an auditive experience to subject. Correlation observed between ECR Hearing Thresholds and Calibrated Ling Sounds detection thresholds is high enough (r2= 0.99) for electrodes electric current adjustment based on patient detection thresholds obtained in a Calibrated Ling Sound Test.