Prevalence and causes of Hearing Impairment

Outline

Prevalence of Hearing Impairment causes of Hearing Impairment Conclusion

Prevalence of Hearing Impairment

Prevalence applies to the total number of existing cases, both old and new.It is extremely difficult to obtain accurate figures because of: definitional problems changing diagnoses presence of multiple disabilities stigma of identification survey problems

Prevalence of Hearing Impairment in Pakistan

•School-aged children between the ages of 5-15 years compromised the study population, with an overall point prevalence of hearing impairment of 7.9% . (Ministry of population welfare in Sialkot,pakistan)

•Prevalence of hearing impairment in Pakistan is 1.6 per 1000 live births. (Ministry of science and technology,2005)

Cont….•It is estimated that the prevalence of profound bilateral hearing loss is 1.6/1000 in Pakistan.(Pakistan medical research council, of national institute of health, Islamabad,june,2010)

•Prevalence of hearing loss in Pakistan was 7-8 per live births.( Lahore – Punjab ministry for social welfare 2014)

Other Prevalence• 16 out of every 1000 school age children have an educationally significant hearing loss.(National Association of State Directors Special Education (NASDSE • 1.3% of all school age students, who receive special education services were of hearing impairment.(U.s department of education,2002).

Causes of Hearing Impairment

Hearing Impairment at birth Hearing Impairment after birth Ear Infection (Otitis Media) Ototoxic Medications Noise

Hearing Impairment at birth (congenital hearing

loss)

Genetic factors Non genetic factors

Genetic Factors An autosomal recessive hearing loss An autosomal dominant hearing loss Genetic syndromes - Usher syndrome - Treacher Collins syndrome - Waardenburg syndrome

Usher syndrome

Treacher Collins syndrome

Waardenburg syndrome

Non genetic factors maternal infections -rubella -syphilis - infection caused by viruses(cytomegalovirus or herpes)PrematurityComplications associated with Rh factor in blood birth injuries Anoxia

Hearing Impairment after birth

(Acquired/Adventitious hearing loss) Meningitis

EncephalitisHead injuriesRepeated exposureChicken pox Flu Mumps

Ear infection (Otitis media)

This middle ear infection occurs in young children because : • Eustachian tube are not develop. • Fluids buildup behind the eardrum.

Ototoxic Medications

Ototoxic medications cause damage to sensory cells used in hearing.Examples : - streptomycin - quinine -amino glycoside antibiotics - cisplatin

Noise

Loud noise can be very damaging to hearing.

Sounds that are louder than 85 db can cause permanent hearing loss. High noise levels first cause temporary hearing loss and then permanent damage to the sensory hair cells within the cochlea.

conclusion

Finding the cause of hearing loss is often not an easy task. Making an accurate diagnosis andfinding a way to manage the hearing loss requires a combination of: • a physical exam• family history• clinical tests (such as genetic tests, MRI, EKG, CT scans, etc.)• ongoing hearing tests with an audiologist

REFERENCEMangal, S.K. (2007).Educating Exceptional Children (An Introduction To Special Education.

Harvard Medical School Center for Hereditary Deafness,2004.

Risk factors for the development of otitis media,2003.

National Institute on Deafness and Other Communication Disorders,2002.