Hearing Loss is a hidden handicap that is often ignored. It can be detected through formal assessment. The incidence increases with age and affects 1/3 of those above 65 years of age. Three in 1000 babies born in Singapore have significant hearing impairment. Often, their parents have normal hearing. These children are at risk of delays in speech, language, intellectual, social and emotional development.
One or more children out of five with unknown cause of sensorineural hearing loss may have genetic Hearing Loss. Genetic Hearing Loss is the leading known cause of Hearing Loss currently, more so than infections or injury. A blood sample is needed for the test. Without testing, the diagnosis can be missed as parents are usually both with normal hearing, and the patients look normal without any other syndromic features.
Testing allows families to obtain a definitive diagnosis such as the cause of Hearing Loss, plan for the child's treatment (certain mutations are related to certain expected severity of Hearing Loss eventually), prognosticate success outcomes of cochlear implantation, assess the risk of hearing loss in future siblings, and avoids further tedious and expensive testing. This test is currently done free for Singaporeans under a BMRC-ASTAR grant. For patients who do not wish to join the study, or for foreigners seeking genetic testing for Hearing Loss, a clinical genetic testing service is also available.
Every hearing impaired child should have a comprehensive hearing test and early intervention to ensure integration into the mainstream society.
Audiological Evaluation
Universal Newborn Hearing Screening Programme
Hearing Loss is the most frequent birth defect. A year's study in Singapore (June 2002 to May 2003) showed that there is a clear need for an early detection and intervention programme. The incidence of hearing loss was found to be 5.2 in a 1000 and those with severe to profound impairment was 3 in a 1000.
The aim of the programme is to diagnose and intervene early so that children may acquire normal speech & language thereby reducing communication disabilities, achieve positive outcomes in academic performance and also enjoy normal social development. This also enhances opportunities for the hearing impaired child to be a part of the hearing world right from infant stage and subsequently receive formal education just like their hearing peers.
For most children with a significant hearing loss, amplification with appropriate counselling and habilitative therapy may be the method of intervention.
Auditory Verbal Therapy
Aural habilitation is aimed at maximising the function of a hearing-impaired individual's hearing in order to listen and acquire spoken language. All children who have been identified with hearing loss are strongly recommended to undergo therapy because listening and talking skills are not automatic after hearing aid fitting or cochlear implantation.
The treatment options for Hearing Loss are as follows:
Before a CI is considered, a series of tests such as an ear examination, hearing evaluation, radiologic (X-ray, MRI) examination, and AVT are necessary.
CI surgery is performed by the otolaryngologist (ENT specialists) under general anaesthesia and lasts from two to three hours. An incision is made just behind the ear to access the mastoid cavity that leads to the middle and inner ears. An X-ray is taken after surgery to confirm the position of the implant. Generally, the patient stays for one or two days after the surgery.
Cochlear Implant Investigations and Therapy
In order to be accepted as a candidate for a cochlear implant, the family is required to attend recommended assessments before the final evaluation can be made. They must also be committed to the clinic's approach. All implantees must undergo regular post-operative assessments.
About one month after surgery, the cochlear implant team will ‘switch on’ the implant. They will teach the parents how to look after the system. The patient will probably be asked to return for a few visits for regular checkups, and readjustments of the speech processor are needed.
Cochlear implants do not restore normal hearing and the benefits vary from one individual to another. There are many factors that contribute to the degree of benefit a user receives from a cochlear implant, including:
Digital, Programmable, and multi-channel Behind-The-Ear (BTE) hearing aids of all styles are available in the market. These aids are suitable for all types of hearing losses, that is, from mild to profound. There are also different types and models of custom hearing instruments, such as Completely-In-The-Canal (CIC), In-The-Canal (ITC), as well as In-The-Ear (ITE). All are worn in the ear to take advantage of the natural hearing process. They are inconspicuous and represent the "elegant" cosmetic solution.
Click here to access our Find A Doctor directory for a list of doctors treating this condition across our NUHS institutions.
