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| EDITORIAL |
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| Year : 2012 | Volume
: 18
| Issue : 1 | Page : 1-2 |
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National deafness program and behavioral enforcement audiometry
Mahendra K Taneja
Editor-in-Chief, Indian Journal of Otology, Delhi, India
| Date of Web Publication | 10-Jul-2012 |
Correspondence Address:
Mahendra K Taneja
Editor-in-Chief, Indian Journal of Otology, Delhi
India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/0971-7749.98274
How to cite this article:
Taneja MK. National deafness program and behavioral enforcement audiometry. Indian J Otol 2012;18:1-2 |
In India, there is around 6.0% incidence of hearing loss, out of which approximately 50% suffer from conductive hearing loss. The universal screening t is a long way, even to the high-risk group, which is due to asphyxias, premature birth, hyperbilirubinemia, low birth weight, and others. Facility of brainstem evoked response audiometry (BERA) is scarcely available. Certainly, auditory BERA tells us about the hearing status of a child on a pass/fail basis, and technically, automated BERA is a simple and reliable screening test, but in a country that is still struggling to spread its wings in controlling deafness, the cost of equipment will definitely be a deterrent to its provision. Auditory steady state response (ASSR) or oto-acoustic emission (OAE) cannot be thought of for routine testing in India. In BERA, in the initial phase below the age of 2 years in all cases, bone conduction (click and tone pip) should be used to fully evaluate the hearing status of the child.
For terminology purpose and to properly divide subgroups, first 4 weeks' (28 days) baby is considered as neonate, up to the age of 3 years is considered as infant, from 3 years to 5 years is considered as preschool, and up to 16 years is considered as school-age child. While assessing the hearing acuity and overall physical and mental development, one has to keep in mind the gestational age, which is the time period between conception and birth. Hence, in premature babies, delayed response is expected. As the baby grows his responsiveness to sound increases and gets mature to adult level at the age of 10 years.
In behavioral observation audiometry (BOA), we assess the baby's response to different frequency intensity and duration of sounds presented. While performing BOA, we have to keep in mind [1] that the individual ear cannot be tested. [2] The judgment of the audiologist may be biased [3] on repeated testing or the baby may be habituated or exhausted [4] The responsiveness varies with the age for the same intensity. Hence, a chart must be made displaying the guidelines of the test and the response expected.
Although the newborn baby responds to 70 db noise by eye blink, eye widening or startle, and between 6 weeks and 16 weeks by arousal, eye blink or eye shift, BOA is more useful between the age of 4 months and 3 years. Above the age of 4 months, baby responds to sound stimuli above 50 db hearing loss (HL) generated by a toy or in free field audiometry. This is the age where BOA can be more useful in our Indian scenario than physiological testing by evoked potential (EP) (BERA).
The infant is able to localize the sound of 50 db at horizontal level between 4 and 7 months. The 10 and 15-month-old baby can localize the sound by downward and upward eye or head movement, respectively. The only caution to be taken is that the baby mimics for every action; hence, family member should not be present and attendant has to be trained not to respond or point during the test. [5]
The child response is enhanced at this age if the toy is lit up or moves with the sound. Again, the duration of the sound is important with the maturation; shorter the duration better is the response. During the test, the child is seated on a clean carpet/floor. There should be a collection of different colorful toys, but out of reach and out of sight of baby. As per the requirement, toy should be used and examinee must keep in mind the comfort level of the baby along with exhaustion and habituation. Usually three out of four tests are suggestive of a positive test. A break of 10 minutes increases the total number of positive responses at the age of 1 year.
The physiological test EP (BERA) is difficult to perform because at times babies do not cooperate and require sedation. The child may be having a conductive hearing loss, which should be assessed by bone conduction (both click as well as tone pip) to assess the high frequency and low frequency, respectively.
I conclude that behavioral enforcement audiometry screening should be a part of the training program of all paramedical workers, specifically auxiliary nurse midwife and American Speech and Hearing Association (ASHA). This is a simple test that can easily be mastered with negligible equipment. In all suspected cases apart from air conduction BERA, bone conduction BERA and tympanometry with acoustic reflex should be performed. Every parent must be made aware about the residual hearing and development of speech with an early use of hearing aid. Signboard display should be placed in every hospital or public place to make the parents aware of early deafness.
| References | |  |
| 1. | Moore JM, Wilson WR, Thompson M. Visual reinforcement of head-turn responses in infants under 12 months of age. J Speech Hear Dis 1977;42;328-34. 
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| 2. | Stanley A. Gerfand. Essentials of audiology. 2 nd ed. Seventh Avenue, New York - 10001: Thieme Medical Publisher, Inc; vol 333. p. 377-96.
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| 3. | Widen JE. Adding objectivity to infant behavioral audiometry. Ear Hear 1977;14;49-57.
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| 4. | Culpepper B, Thompson G. Effects of reinforcer duration on the response behavior of preterm 2-year-olds in visual reinforcement audiometry. Ear Hear 1994;15:161-7.
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| 5. | Northern JL, Downs MP. Hearing in children. 4 th ed. Baltimore: Williams and Wilkins; 1991.
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