Neonatal Hearing Screening

Hearing screening was first done over 100 years ago using a whispered voice test. Sweep testing with pure tone audiometer was other method employed in the fifties. Search for neonatal hearing screening methodologies was prompted by the fact that early intervention in cases of hearing impairment will reduce later disability. The concept of targeted screening of "at risk" babies became popular as it was more cost-efficient. The proponent of universal neonatal screening argue that the high risk register misses 50% of loss. Ironically 90% of the infants with hearing impairment are born to parent with normal hearing and his fact goes in favours of universal screening. Screening should be done by trained personnel. Hearing loss is expressed in the early years and therefore the optimal age for screening is first 3 years. School age screening may be used to detect progressive hearing impairment only. Automatic BSER, traditional BSER and Oto-acoustic emission have emerged as reliable screening methods. Screening tests for hearing should have a sensitively and specificity of 90%. Follow-up is vital to pick-up progressive hearing loss. Availability of ancillary facilities like audiological services speech language pathologist, ENT specialist, paediatrician and teachers for the deaf are equally important Benefits of screening include prevention, maintenance of adequate audition and habilitation

Causes of bilateral sensorineural hearing loss in school children

A study of children in Special schools in Karachi Pakistan, was conducted to find out the factors responsible for hearing impairment. Information was collected through a questionnaire sent to the parents of all the hearing impaired children registered in these schools. In total 657 [60%] completed questionnaires were returned. 100 children were randomly selected for general physical, ear and eye examinations and pure tone audiometry, tympanometry, blood and urine tests, IgG for rubella and a skull X-ray. The causes of hearing impairment was rubella in 2% of the children, jaundice in 4.5% meningitis in 5.2% measles in 11.4%, ototoxicity in 0.7%, prematurity in 0.7%, and genetic factors in 27% of the children investigated. In 80% of the children the mode of inheritance was recessive and in 15% it was domininant.. 5% of these cases were syndromal. The rate of parental consanguinity among hearing impaired children was 58%. Average hearing loss in 94% of the study group was above 80 dBHL. The mean age of diagnosis of hearing loss was 19.1 months in 51% children the hearing impairment was diagnosed by the age of one year. Parents suspected the hearing loss in 61% of cases