Successful cochlear implantation in a patient with MELAS syndrome

Objective: To describe methods of assessing cochlear implant candidacy in p atients with potentially significant peripheral and central nervous system (CNS) degeneration. Study Design: A patient with a degenerative CNS disease (MELAS syndrome) undergoing evaluation for cochlear implantation is descri bed. Setting: This study took place at a tertiary care center. Patient: A patient with mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) who had cortical blindness and profound sensor ineural hearing loss was evaluated and rehabilitated with cochlear implanta tion. Interventions: Pure-tone audiogram, behavioral responses to promontory stim ulation electrical auditory brainstem response, and electrically evoked mid dle-latency responses (MLRs) were used to assess eighth nerve, auditory bra instem, and cortical auditory pathways. Cochlear implantation with Cochlear Corporation mini 22 implant was performed. Results: Repeatable electrically evoked MLRs and behavioral responses to pr omontory stimulation documented the presence of auditory cortical responses . Successful implantation resulted in open set speech recognition and commu nication using the auditory/oral mode. Conclusion: This report describes successful implantation in a patient with MELAS syndrome and demonstrates the ability to preoperatively confirm the integrity of brainstem and cortical auditory pathways despite significant C NS degeneration.