Sensorineural hearing loss (SNHL) is the defect of transmission of sound from cochlea due to this it results in sound distortion and brain is unable to perceive the correct sound. United States Census has reported 3% population suffering from hearing defect and most of the cases are due to congenital or genetic defects. Medical reasons for SNHL hearing loss include prebirth infections and teratogen exposure, perinatal issues include prematurity, low birth weight, anoxia and/or low Apgar scores, hyperbilirubinemia, or sepsis. In the infants, infections, such as meningitis or mumps can cause SNHL. Brain injury leads to both SNHL and CHL (Shah & Lotke, 2008).
Congenital hearing loss is the hearing impairment right from the birth. In the congenital bilateral sensorineural deafness both ears are affected. This disability can be genetic or it can form during intrauterine growth (prenatal) or at the time of birth due to other factors, such as prenatal infections and environmental and teratogenic factors (CGC genetics, August 2009). The genetic factors are responsible for 50% of congenital hearing loss in which syndromic factors contribute to 30%; while nonsyndromic factors contribute to 70% ((CGC genetics, August 2009). This congenital bilateral sensorineural deafness is the most common hearing disorder in developed countries. It has been reported that 0.2% newborns suffers from bilateral permanent sensorineural hearing loss of ≥ 40 dB. When the child reaches his adolescent age, this figure is increased to 0.33%.
Hearing impairment might lead to delaying of all the developmental domains including cognitive, emotional, social, and speech and language impairment (Polinski, 2003). Speech and language impairment hampers social, behavioral and learning growth due to faulty communication. Language disorders make the children nonreceptive of other’s language and also they are not able to express themselves properly and adequately. This consequently leads to undeveloped ...Show more