Identification of cochlear and Retro cochlear causes in patients with tinnitus

This study was designed to identify the possible underlying site of lesion in patients with tinnitus through using Transient Evoked otoacoustic Emissions [TEOAEs], Auditory Brainstem Response [ARR] and Electrocochleography [ECOchG]. Forty subjects complaining of tinnitus were examined. The control group consisted of'24 ears with normal hearing sensitivity not involved with tinnitus. The study group comprised of 36 ears with hearing loss and 20 ears with normal hearing thresholds. TEOAEs revealed that 88.8% of tinnitus ears with hearing loss partially passed or failed to pass the emissions. Interestingly, 20% of tinnitus ears with normal hearing full in the fail to pass category. There was statistically significant difference between control amid study group for absolute latency of wave 1. In ABR test. EcochG results showed that there was no statistically significant difference of the summation potential [SP], action potential [AP] and SP/AP ratio. On individual analysis, two subjects showed increased SP/AP ratio who were finally diagnosed as having Meniere's disease. One subject revealed manifestations of retrocochlear lesion in ABR test results and proved later to have cerebello-pontine angle mass. The combination of TEOAEs, ABR and EcochG is useful to identify site of lesion in tinnitus subjects. EcochG is valuable in diagnosis of endolymphatic subjects. EcochG is valuable in diagnosis of endolymphatic hydrops, ABR for detection of retrocochlear lesion while TEOAEs is very promising for early detection of hidden cochlear pathology

Incidence of ototoxicity in patients receiving cytotoxic medication

This study was done with the objective to evaluate the efficacy of otoacoustic emission in early detection of cochlear lesion due to ototoxic drugs. A total of thirty five patient twenty of them were receiving cisplatin and fifteen were receiving vincristine. They were receiving the therapy at the Oncology unit, Assiut university hospital. All study patients were submitted to complete audiological evaluation including pure tone audiometry, speech audiometry, Immittancemetry test and otoacoustic emissions [OAE] including, Transient evoked otoacoustic emissions. This evaluation was done before drug therapy and after each subsequent course of therapy. Comparisons were made between basic pre-therapy evaluation and the serial follow up for three mouths [by audiometry and otoacoustic emission test]. After therapy, significant evaluation of pure tone thresholds were demonstrated in high frequencies [4-8 KHZ] in 67% of patients receiving cisplatin and 13.3% in patients receiving vincristine therapy. There were a significant decrease in OAE amplitude specially at high frequency band; 3-4 KHZ in both groups even in patients with no changes in their audiometric thresholds. In conclusion vincristine and cisplatin therapy could produce Ototoxicity due to cochlear lesion and TEOAEs were more a sensitive than audiometric test in early detection of cochlear Ototoxicity and could be used for its monitoring

Study of noise, hearing impairment and hypertension in Egypt

This study included 295 workers of Assiut Generation Station [Upper Egypt]. Two hundred and twenty-one of the workers were exposed to different levels of noise [80 to 107 dBA] and the remaining 74 were used as a control group. There were no significant differences in risk factors viz age, duration of work, body mass index, weight, height, smoking, and previous work as determined by a questionnaire. The relationship between occupational exposure to noise, the degree of hearing loss and hypertension was determined. The results showed that there were statistically significant differences between the average hearing threshold levels of the two groups [P<0.01] which were more in those workers exposed to noise than in the control group. The mean systolic and diastolic blood pressures were also statistically significantly different in the two groups [P<0.001] and they were positively correlated [P<0.001] to the percentage of impairment of the whole body at 4 and 6 kHz, and hearing disability at 0.5, 1,2, and 3 kHz. Stepwise multiple regression analysis revealed that age, noise level and body weight could each be used as a predictor of hypertension. A predictive formula was derived between the amount of hearing loss and blood pressure in the subjects exposed to occupational noise

Study of noise hearing impairment and hypertension in a noisy industry in upper Egypt

This study included 295 workers of Assiut Electricity Generation station [Upper Egypt]: 221 of the workers were exposed to different levels of noise [80-107 dBA], and the remaining 74 in administrative Jobs not exposed to noise, were used as a control. There were no significant differences in risk factors, viz; age, duration of work, body mass index, weight, height, smoking and previous work, as determined by a questionnaire. The relationship between occupational exposure to noise, the degree of hearing loss and hypertension was determined. The results showed that there was statistically significant differences between the average hearing threshold levels of the two groups [p<0.01]. The mean systolic and diastolic blood pressures were also statistically significantly different in the two groups [p< 0.001] and they were positively correlated [p< 0.001] to the percent impairment of the whole body at 4 and 6 KHZ, and hearing disability at 0.5,1,2 and 3 KHZ. Stepwise multiple regression analysis revealed that age, noise level and body weight could each be used as a predictor of hypertension. A predictive formula was derived between the amount of hearing loss and blood pressure in the subjects exposed to occupational noise

Noise-induced hearing loss

A total number of 225 noise exposed subjects chosen from different places in the Spinning and Weaving Factory of Assiut and the Red Sea Phosphate Mines and fifty non-exposed subjects were chosen as controls. All the subjects were subjected to clinical and audiometric examination. Statistical analysis was done on the results of the work and reveled that: There was no pre-employment audiograms included within the fields of the workers. The noise-induced hearing loss is directly proportional to noise level and length of exposure. The threshold of hearing of our controls was found to be higher than other presbyacusis data pointing to the importance of sociocusis factor in Egypt. The maximum hearing loss occurs at 4 KHz followed by the other frequencies, and the major hearing loss occurs after 10 years. Although the maximum permissible noise level is 90 dB, we noticed that exposure to noise level of 80-90 dB was harmful