الفهرس 
Verification of Hearing Aid FittingOnly 14 pages are availabe for public view
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Abstract
Recent evidence indicates that children with sensorineural hearing loss achieve language abilities similar to hearing peers if comprehensive intervention services are provided by 6 months of age early detection and intervention through the concept of universal newborn hearing screening programs are believed to be critical steps toward proactive management of those children
Management of hearing loss as early as possible, includes fitting the infant with an aid that properly compensates for the loss and verifying that the aid provides adequate benefit Clinical hearing assessments define the auditory thresholds for a wide range of frequencies. This information assists clinicians in prescribing an aid with the proper acoustic parameters to amplify the speech spectrum at a comfortable level
To verify the hearing-aid fit, functional gain is determined together with a subjective response from the subject However, these modes are limited or impossible to apply in infants and other non-cooperative individuals Consequently, there is a great need for an objective tool which can help to predict the aided and unaided audiogram and which, when coupled with the electroacoustic measurements, can provide sufficient data for appropriate hearing aid prescription.
Summary
107
More recently, the advent of the auditory steady-state response (ASSR) as a clinical tool for objective audiometry in infants has shown a promise as a useful way of determining aided thresholds Unlike the ABR, the ASSR is evoked by continuous stimuli modulated in amplitude and frequency. After the initial few stimuli, the response stabilizes and thereafter contains a constituent frequency component that remains constant in amplitude and phase over time These stimuli are therefore unlikely to be distorted by amplification in either the sound-field speaker or hearing aid, and frequency-specific thresholds can be measured across the frequencies important for speech.
In this study total number of 20 children (40 ears) was selected with severe to profound hearing loss with their age ranged from 4 to 10 years with good mentality and regular users of hearing aid for at least three months. All children was tested using a double wall sound treated room model Amplisilence E,two-channel Audiometer GSI model 61 calibrated according to ANSI S.3.6, 1996 and connected to headphones TDH 39, bone vibrator B71 and two loudspeakers for sound field testing, acoustic Immittancemeter Madsen GSI TYMPSTAR model and auditory Steady-State Response evoked potential system model GSI AUDERA.
Results showed that behavioral thresholds were significantly better than ASSR thresholds at all frequencies
Summary
108
tested. Statistical significant correlation between PTA & ASSR at all frequencies.
The difference between ASSR thresholds and behavioral threshold in general might be attributed to the effect of background noise and harmonic overtones of the response that could not be calculated, and there is significant correlation between the aided behavioral threshold and aided ASSR.
It was concluded that Aided sound field ASSR and aided behavioral threshold showed strongly correlated results and this indicates that ASSR may be a good alternative method for the measurement of aided hearing level in infants and children.
Throughout this study it is recommended that Aided ASSR can be used in difficult to test children as an objective measure to assess the benefit from the hearing aid.