The results showed that the genes of GSTM1 and GSTT1 had no combined action,those with GSTM1(-)and GSTT1(-)genotype had high risk of developing noise-induced hearing loss than those with GSTM1(+)and GSTT1(+)(OR=1.11,2=0.16,P>0.05).
By analysis of multivariate condition Logistic stepwise regression mode, family history of hearing loss( OR =16.945,95%CI 1.21-237.369) and craniofacial anomalies ( OR =6.703,95%CI 0.61-73.85)were 2 independent risk factors of newborn hearing loss.
Conclusion: The medical history and auditory analysis of the members of the four pedigrees show that the hearing impairment in these pedigrees are nonsyndromic autosomal recessive hereditary hearing loss. The screening of the GJB2 ,GJB3,GJB6,and mitochondrial genes show that the F,G pedigrees are related with GJB2 mutations.
Results The ratio of hearing lost before operation was 74%, the abnormal tympanic graph rate was 80% (82% before 3-year-old). Hearing was improved at a certain degree 6 months after operation, the abnormal tympanic graph rate was 42%. The G + and G - positive rate of organism culture of tympanic scretion was 23% and 24%, most organisms were low poisonous and conditional infective.
The organism culture of tympanic secretion was done before operation. Results The rate of hearing lost before operation was 74.17 %,the abnormal tympanic graph rate was 20%( 81.6 % before 3 year-old). Hearing was improved at a certain degree 6 months after operation,the abnormal tympanic graph rate was 58.33 %.
In addition to congenital ichthyosis he had also strabismus, horizantal nystagmus, bilateral neurosensory hearing loss, hepatomegaly and splenomegaly.
Hearing loss up to 30 dB (preserved socially adequate hearing) was found in 25 workers.
Some measures for preventing occupational noise-induced hearing loss were suggested.
Conclusion: The primary symptom of the patient was unilateral hearing loss.
In 73% of the cases the EAEP indicated the retrocochlear site of the lesion; in 27%, however, the results did not localize the exact site of the lesion owing to a lack of waves I, II and III due to a pronounced hearing loss.