TRANSIENT DEAFNESS IN YOUNG CANDIDATES FOR COCHLEAR IMPLANTS
  
Attias J (1,2),  Raveh E (3)
 
(1) Department of Communication Disorders, University of Haifa, Haifa; (2) Institute for Audiology and Clinical Neurophysiology; (3) Department of Otorhinolaryngology, Schneider Children’s Medical Center of Israel and Rabin Medical Center, Petah Tiqwa, affiliated with Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.

This study describes 8 infants who were diagnosed with auditory neuropathy (AN) associated with severe to profound neural hearing loss shortly after birth. Unexpectedly, on repetition of the tests 7-12 months later, all infants showed full or partial recovery.  The follow-up electrophysiological patterns in 7 of the patients were characterized by the appearance of wave I, followed by wave III and V, reflecting synchronization of auditory pathways and improvement in auditory nerve function.  In the 7th case the recovery started from wave V to III and I.  Fluctuations in behavioral and electrophysiological measures were found. While 5 infants had risk factors to congenital hearing loss, the other two infants had no risk factors.  Suspected causative or contributory factors were neonatal hyperbilirubinemia, hypoxia, ischemia, and central nervous system immaturity, alone or in combination. These findings indicates that lack of an ABR does not necessarily mean no hearing AND that situation when AN exists can improve. Thus, although cochlear implants may yield better auditory performance if applied early, they should be considered a therapeutic option only after repeated measures prove persistent auditory neuropathy and no child should be considered for an implant until a behavioral measure of hearing is reliably obtained. 

E-mail: attiasj@netvision.net.il