الفهرس 
Introduction and rationaleOnly 14 pages are availabe for public view
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Abstract
Auditory evoked potentials (AEPs) are required to estimate hearing thresholds at audiometric frequencies for infants and young children who cannot be tested using conventional behavioral measures. Auditory brain stem response (ABR) is the most commonly used test in clinical practice to estimate the degree of hearing loss , but the auditory brainstem response (ABR) cannot differentiate between severe and profound SNHL ASSR is a new available tool used to estimate hearing thresholds due to its objectivity, frequency specificity, its continuous stimuli that can be presented at higher levels (Up to 120 dB HL) than other AEPs so, can help in detection of children with absent ABR waves, its advantage in assessing 8 frequencies at both ears simultaneously moreover, it does not need subjective analysis and interpretation as response determination is calculated by a computer. The frequency specificity and the intensity stimulation advantage uniquely qualifies the ASSR for investigation of residual hearing in young and difficult-to-test cochlear implant candidates. Accordingly, this study was designed to determine the hearing threshold levels in children with severe to profound sensorineural hearing loss using the ASSR audiometry and to explore the extent that the ASSR can predict the behavioral hearing thresholds in those children. In this study, a total number of 40 children with absent ABR waves were included. Their age ranged between 1 to 5 years . All children of the study were subjected to careful history taking, otological examination, basic audiological evaluation in the form of play audiometry and sound field audiometry. Click-evoked ABR was done , TEOAE was done and ASSR was tested at 0.5, 1, 2 and 4 kHz . Results showed that ASSR thresholds were significantly better than ABR threshold at all frequencies tested. It was concluded that absent behavioral sound field response and/or absent click ABR do not preclude the possibility of residual hearing that could be detected using ASSR. The reliability of ASSR for detecting hearing sensitivity thresholds increased at the mid frequencies (0.5, 1 & 2 KHz) than4 KHz. It was recommended to include ASSR for objective assessment of hearing threshold in children with absent behavioral threshold detection and/or absent click evoked ABR to detect the presence of useful residual hearing to select the appropriate way for intervention either the use of hearing aid or cochlear implant (C I).