Effects of electrical stimulation rate in genetically confirmed pre- and post-Synaptic auditory neuropathy in children
摘要
Auditory Neuropathy Spectrum Disorder (ANSD) affects neural transmission of auditory signals and is classified into presynaptic and postsynaptic types. Cochlear implant (CI) outcomes depend on lesion site and stimulation rate, with slower rates potentially benefiting impaired conduction.
MethodsSeventy children aged 2–7 years with genetically confirmed ANSD received the Nucleus CI system. Participants were grouped as either pre- or post-synaptic and randomly assigned to one of three stimulation rates: 500, 900, or 1800 pulses per second (PPS). Assessments at 3 and 6 months included aided thresholds, Persian versions of the Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR), cortical P1 latency and amplitude, and Electrically Evoked Compound Action Potential (ECAP) via Neural Response Telemetry across apical, mid, and basal electrodes.
ResultDespite comparable aided thresholds, presynaptic ANSD cases showed consistent ECAP responses and greater improvements in P1 measures and CAP/SIR scores, particularly at low and moderate rates. ECAP amplitude increased and latency decreased over time in this group, with no significant rate–time interaction. Postsynaptic cases showed limited ECAP responses and smaller functional gains.
ConclusionLesion site critically influences CI outcomes in ANSD. Presynaptic children demonstrated physiological and functional improvements, especially at lower rates, consistent with preserved neural integrity. Postsynaptic cases showed restricted responses, likely reflecting demyelination. Findings support individualized CI programming guided by genetic and neural profiles.