Auditory and Vestibular Research Journal
Year:2004 | Volume:14 | Issue:22|Papers Count:8

Objective: Comparing analog and digital hearing aids reducing disability caused by hearing deficiency among moderate to severe sensorineural hearing-impaired persons.Method and Material: This descriptive - analytic study was carried out on two groups of subjects participated in this study in some audiology clinics of hearing aid since May 2002 to October 2003. Twenty subjects wore analog hearing aids and twenty one subjects wore digital hearing aids. In this study, no subject had previous middle ear or psychological problems. APHAB questionnaire was completed before using hearing aid and 2 months after to determine benefit of hearing aid use.Results: Total score mean of APHAB inventory before and after use of analog hearing aids were 52.215±6.420 and 32.300±3.443 respectively. Also total score mean of APHAB inventory before and after use of digital hearing aids were 54.9252±9.028 and 26.321±10.916 respectively. There was no significant difference between total mean score of APHAB inventory before and after using analog and digital hearing aids (P=0.058). While there was significant difference between total mean score of APHAB questionnaire before and after use of analog hearing aids (P<0.001) and also before and after use of digital hearing aids (P<0.001).Moreover age, gender, literacy level, occupation, degree of hearing loss and manner of hearing aid usage did not have significant effect on APHAB results. Configuration of loss had significant effect on aversiveness subscale before and after use of analog hearing aids (P=0.008).Previous experience and duration of hearing aid usage had significant effect on aversiveness subscale before and after use of digital hearing aids (P=0.043) and (P=0.024), respectively, while all of these three items did not have significant effect on total mean score of APHAB inventory and also total mean scores of three subscales of ease of communication, reverberation and background noise.Conclusion: Comparing to analog hearing aid, digital one is significantly beneficial for reverberation and background noise for hearing-impaired persons, but it has no. benefit for ease of communication and aversiveness that may be arose from effects of the individual expectation, psychological and personal factors.

Objective: Survey and comparison between the physical characteristics of Distortion - Product Otoacoustic Emissions of 1- 59 day-old normal-hearing newborns referred to TUMS, Rehabilitation School, Audiology department, 2002Method & Material: This analytical-descriptive study was conducted on the ears of 102 easy method selected newborns. The tests included: otoscopy, BOA, Immittance audiometry, DPOAEs, and ABR if necessary. The amplitude and frequency of 2f1-f2 emissions of DPOAEs evoked by two pure tones (L1=65 dBSPL, L2=50 dBSPL and f2/f1=1.2) were also calculated.Results: 1- All normal hearing newborns have normal DPOAEs. No significant difference was observed in test-retest.2- The amplitude of the DPOAEs to the right ear is significantly greater than the amplitude of the left ear (P<00.05).3- No significant difference was observed between newborn's DPOAEs in terms of their gender.Conclusion: DPOAEs could be measured quickly and noninvasively and are excellent tools for the screening of newborn hearing loss. The results are valid only within the Context of this research.

Objective: To assess neonates and children suffering from meningitis, during the critical and recovery periods, using ABR, EOAE and Behavioral Audiometry.Method and Material: 40 neonates to 12-year-old children were assessed.Using ABR test, the hearing of these cases was evaluated during the critical period-that is, 24-72 hours following the diagnosis. This test was repeated when patients recovered from meningitis-that is 24 hours before discharge (recovery period) Hearing function, again, was assessed 7-14 days following discharge through Immittance Audiometry, Behavioral Audiometry (PTA, SF and BOA). And EOAE (TEOAE and DPOAE) tests procedures.Findings: During the critical period, ABR test revealed normal hearing in 35 patients (87.5%) and severe to profound sensorineural hearing loss (unilateral and bilateral) in 5 patients (12.5%-girl=4, boy=1). The same results were obtained in reevaluation in the recovery period.On the other hand, 7-14 days after of discharge, Immittance Audiometry and Behavioral Audiometry (including PTA, S.F and BOA tests), confirmed the mentioned results (cross - gcheck).EOAE test (DPOAE and TEOAE) in 35 normal hearing patients (according to ABR test), showed normal cochlear function. 2 out of 5 cases suffering from severe to profound sensorineural hearing loss revealed normal cochlear function. According to EOAE results, abnormal cochlear function was evident in 3 patients.Conclusion: ABR, EOAE tests, and Behavioral Audiometry in children meningitis during the critical period and recovery period can be used to diagnose any degree of hearing loss with a high level accuracy. The result of present study is confirmed by previous investigations.

Objective: To determine SOAE, TEOAE, and DPOAE, characteristics in normal-hearing school boys.Method and Material: This cross-sectional study was conducted on 7-11 year-old normal - hearing boys (n = 100) living in 12th zone of Tehran. OAEs also performed and investigated if otoscopy, pure tone and imrnittance audiometry were normal.Both handedness and ear effects was also considered.Results: 31% had SOAEs. No significant difference between the right and left ear SOAEs frequency and amplitude means.1, 3 kHz and total response TEOAEs amplitude was significantly different between two ears. There was no significant difference between both ear DPOAEs amplitudes, whereas the left - handed boys' DPOAE amplitude is greater than the right - handed ones' amplitudes.Conclusion: As some results including equal SOAEs of both ears, no difference between both ears SPOAEs amplitude, and handedness effect on the amplitude do not agree with other studies, these finding should be considered in testing OAEs of school boys.

Objective: Determining the prevalence of hearing loss and correlated factors in clients referring to audiology clinic of Buali hospital.Method and Material: This cross-sectional analytic-descriptive survery was carried out on six thousand and twenty ears of 3010 clients (1651, a; e and 1359 female) in Audiology clinic of Buali hospital, during Sept 2000 to Sept 2001.Results: Hearing loss is the most common reason for referring the clients (20.5%). 1319 ears (21.9%) Showed sensorineural hearing impairment and conductive and mixed hearing loss are observed in 1059 (17.6%) and 234 (3.9%) ears, respectively.Hearing loss degree most cases is mild (14%) in both ears. There is no significant difference between male and female hearing threshold means (p>0.05), but a significant difference between hearing thresholds is observed in terms of age (p<0.05). Audiogram configuration in most cases is flat (55.1 %). Otoscopic examination reveals abnormal condition in 2333 ears (38.8%).37.2% of the studied cases have abnormal tympanogram mostly type B (15.9%).2.2% of the clients wear hearing aid that mostly have B.T.E ones (1.5%). 6.2% of the clients, depends on their hearing impairment type and degree need rehabilitation services.Conclusion: The results are Valid only in the context of this study and its generalization needs further researches.

Objective: To measure external ear resonant amplitude and frequency in children (3-7 years old) and to compare with adult measures.Method and materials: The external car resonance peak amplitude and frequency of 63 children 3-7 years old were recorded. All of the children had normal tympanogram and there was no cerumen in external auditory canal.20 adult of 21-24 years old (10 male, 10 female) were selected in order to compare with children that had normal tympanogram.The tests included: 1- otoscopy 2- tympanometry 3-microphone probe tube test.Results: The average of resonance peak frequency for children and adult is 4200 Hz and 3200 Hz, respectively. The resonance frequency of children had significantly difference with average of resonance frequency in adults. The average of resonance peak amplitude for children and adult is 17.70 dB and 17.17 dB, respectively.Conclusion: Resonant frequency and amplitude affect the hearing aid prescription and fitting process and calculating insertion gain; so, this measures seem should be considered in children hearing aid fitting.