Overview of Behavioural and Objective Techniques in Screening.pptx

Hearing loss, being an invisible disability, can remain unnoticed, particularly since typically developing children might not start speaking until around the age of two. Consequently, if hearing loss isn't identified through newborn hearing screening initiatives, it frequently remains undetected beyond 18 months of age, especially among children without any medical conditions or additional disabilities.

1. Overview of Behavioural and Objective Techniques in Screening Hearing Loss Mr. Ambuj Kushawaha Research Scholar AIISH- MYSORE

2. Introduction The critical period for development of the auditory system and speech commences in the first 6 months of life and continues through 2 years of age. Hearing loss is not a visible disability, and even normal hearing children may begin talking up to 2 years of age.

3. Continue if hearing loss is not detected through newborn hearing screening programs, Specific linguistic experience in the first 6 months of life, before meaningful speech begins, affects infants’ perception of speech sounds and their capacity to learn.

4. In Concert with recommendations of the Joint Committee of Infants Hearing (JCIH, 2000) and The National Institute of Deafness and other Communication Disorders (NIDCD-1997), early hearing detection and intervention programs must use screening measures that demonstrate certain response and measurement characteristics.

5. The response should be capable of being measured reliably under a wide variety of conditions. The response should have predictive value i.e. it should be present in nearly all norma- hearing infants and abnormal in nearly with hearing loss.. These are as follows-

6. A screening procedure should use objective criteria to define both the method for technically correct screening tests and the guideline for pass versus refer outcome. The procedure should achieve a low referral rate for follow-up, prevent unnecessary cost and parental anxienty . These are as follows-

7. Screening A Variety of procedures are presently used in hearing screening programs for children form infancy through high school. Not a single procedure is effective in identifying all hearing loss.

8. Type of hearing Screening procedures. Developmental Checklist High Risk Resister. Auditory Brainstem Response (ABR). Otoacoustic Test Visual reinforcement audiometry

9. Developmental Checklist It has been to obtain information from parents or other caregivers regarding the auditory behaviours of children. It is useful to obtain functional information regarding auditory and oral development, especially for very young children or children who are difficult to assess.

10. According to Northern and Down (1974) Developmental Checklist At 0 to 4 Months- When he was sleeping quiet, did sudden noise awaken him Momentarily ? Did he cry at very loud noise ? At 4 to 7 Months- Did he turn to find towards sound that was out of his sight? Did he keep on making babbling noises of a large variety at 5 and 6 months ? At 7 to 9 Months- Did he turn to find the source of sound out of his vision ? Did he gargle or coo to voices or sounds that he could not see ? Did he make sound with rising and falling infections?

11. Developmental Checklist At 9 to 13 months- Did he turn and find a sound anywhere behind him? Did he begin to imitate some sounds what Specific sounds did he say ? At 13 to 24 Months- Did he hear you when you called from another room? Did his voice sound normal? Click Here

12. Family history of permanent childhood sensorineural hearing loss. In utero infection such as cytomegalovirus, rubella toxoplasmosis, or herpes. Craniofacial anomalies, including those with morphological abnormalities of the pinna and ear canal. High-Risk Resister Professional leadership in infant hearing and early detection has largely provided by Joint Committee Infant Hearing (JCIH)- 1972

13. They provided by the historical risk factor of hearing loss- Family History Hyper Bilirubinemia requires an exchange. Congenital Infection (TORCH- toxoplasmosis. Other Include syphilis, Rubella, Cytomegalovirus, herpes simplex) Craniofacial anomalies (Defects) Birth weight less then 1500 gram Bacterial meningitis Apgar score of <3 at 5 minutes Ototoxic medications including, but not limited to, the aminoglycosides used for more than 5 days. Associated with syndrome. Click Here

14. Auditory Brainstem Response An auditory brainstem response (ABR) test is a safe and painless test to see how the hearing nerves and brain respond to sounds. It checks your child’s brain’s response to sound. The test is mostly done on infants and children who may not be able to respond to behavioral hearing tests because of their age. The child will not feel anything during this test.

15. ABR and Automated auditory brain stem response are electrophysiological procedures used for hearing screening based on brainstem response to sound. When used as a screening procedure ABR primarily detect greater hearing losses then 30dB in the frequency range 1000 to 4000Hz.

16. How is the test done? The test can only be done when your child is sleeping. Small electrodes (sensors that measure brain activity) will be placed on your child’s forehead and earlobes or mastoid bone, and earphones will be placed over his or her ears. An electrode gel will be used on your child’s head and ears so that there is good contact between the skin and the electrodes. Once your child is sleeping, sound will be played through the earphones. His or her brain’s response to this sound will be recorded through the electrodes and recorded on the computer. Click Here

17. Otoacoustic Test The OAE (Otoacoustic Emissions) test checks part of the inner ear’s response to sound. The test is mostly done on infants and children who may not be able to respond to behavioral hearing tests because of their age.

18. The OAE test determines how well your inner ear, or cochlea, works. Your ear is made up of three parts — The outer The middle The inner ear.

19. Otoacoustic emissions are sounds given off by one small part of the cochlea when soft clicking sounds stimulate it. The sound stimulates the cochlea, the outer hair cells vibrate. The vibration produces a nearly inaudible sound that echoes back into the middle ear. This sound is the OAE that is measured. Click Here

20. If you have normal hearing, you will produce OAEs. If your hearing loss is greater than 25–30 decibels (dB), you will not produce these very soft sounds. This test can also show if there is a blockage in your outer or middle ear. If there is a blockage, no sounds will be able to get through to the inner ear. This means that there will be no vibration or sounds that come back

21. Visual reinforcement audiometry (VRA) is a behavioral test of hearing best suited for infants from six months to around two and a half years of age.

22. The aim of VRA is to identify minimum response levels at different frequencies to get information on the child's hearing. the child sits on the parent’s lap in a sound booth (booth with a window that is insulated from outside noise), where speech sounds, and tones are presented through two speakers in the corners of the booth. Click here

23. The typical response is a head turn in the direction of the speaker, reinforced by lighting an animated toy above the speaker. Once the child is conditioned to respond to the sound, intensity of the signal is decreased to determine his or her child’s hearing sensitivity.

24. Behavioural Observation Audiometry The audiologist will be measuring your child’s hearing levels for several different frequencies (pitches)of sound.

25. BOA is a test used to observe hearing behaviour to sound when VRA is not possible. This is often used for infants less than 6 months of age or who are developmentally not able to turn their head towards a sound. Additional testing is often necessary to supplement BOA

26. In BOA the testing of infants and young children is accomplished without reinforcement of responses and rests on the subjective observation of response under structured conditions In BOA, Infant’s response is observed to a variety of moderate to high-intensity stimuli, such as calibrated noise makers, to observe startle, use widening, localization or cessation of activity.

27. Stimulus Used When planning the test session, it is important to keep in mind: The infant will provide only a limited number of response Speech Signals (e.g. bha-bha-bha , pa-pa-pa) Warbal Tone Narrowband Noise/Speech Noise Various handheld noise makers (Rattles, Drums) Click here

28. Expected responses (stimulus & Level of Response) Newborn Period (0-4 months) Normal infant is aroused from sleep by sound signals of 90dB in noisy environments- 50-60dB in quiet . (3-4 Months) Normal Infants begins to make a rudimentary head turn toward a sound.- Signal 50-60dB (4-7 months) Baby turns head directly toward the side of signals 40-50 dB but cannot find it above or blow.

29. (7- 9 Months) Baby directly locates a sound source of 30-40 dB (Spl) to the side and indirectly below. ( 9-13 Month) Baby directly located a sound source of 25-35 dB (SPL) to the side and below. (13-16 Months) Toddler localizes directly sound signal of 25-30 dB (SPL) to the side and blew; indirectly above (16-21 Months) Toddler localizes directly sound signals of 25-30 dB (SPL) on the side, blow and above (21- 24 Months) Child locates directly a sound signals of 25dB (SPL) at all angle..

30. Conditioned Play Audiometry (CPA) This is a hearing test in the form of a game and is typically used for children 2 to 4 years developmental age.

31. The child will be taught how to do a specific action, such as dropping a block in a bucket or feeding Cookie Monster, every time he or she hears a tone. Tones are presented at different pitches through headphones or speakers. This test relies on the cooperation of your child to sit still and listen

32. These activities are assumed to be interesting to children, are within their motor capability and represent a specific behaviour that is used to donate an response to a stimulus. The Challenges in play audiometry teach the child to wait, listen and only respond with the play activity when the auditory signal is presented

33. Acoustic Immittance Audiometry Acoustic Immittance measurement Objective Measurement Impedance= Opposition to flow of Sound through auditory system Admittance= ease with which sound flows through the auditory system

34. Acoustic Immittance measurements have consisted of three procedure Tympanometry Peak Pressure: This is the air pressure of the air contained within the middle ear. It is shown by where the “peak” of the tympanometric trace falls along the pressure axis. Static Admittance: the most acoustic energy absorbed by the middle ear system (the vertical peak of the tympanogram tracing).

35. Acoustic Reflex: The acoustic reflex is a feedback loop of the auditory system . It occurs when stapes bone, in the middle ear, gets pulled due to the contraction of the stapedius muscle in response to sounds of sufficient intensity

36. Procedure A probe is placed in the ear canal consisting of three-part: Loudspeaker Monometer pressure pump Microphone

37. A 226 Hz ton introduced by the loudspeaker while the manometer pressure pump automatically and slowly varies pressure in the ear canal form +200 to -400 dapa (Deca pascals) In the meantime, the microphone measures the change in intensity in the ear canal as pressure varies.

38. Brain-evoked reinforcement Audiometry is an objective test used to determine how electrical waves are sent from the eighth cranial nerve to the brainstem in response to click noises delivered through the ear.

39. The BERA hearing test is an electrophysiological test procedure that helps identify and study the electrical potential generated at various levels of the auditory system, starting from the cochlea to the cortex. BERA provides a rapid and efficient way to screen for deafness in infants. Hearing test is the most specific and sensitive test for brain stem dysfunction as it is one of the most important objective methods for evaluating the peripheral auditory system in neonates, infants, sedated and comatose patients, and other people who don’t understand the language.

40. Why is Brain Evoked Response Auditory (BERA) Test done? This test is performed for various different reasons such as: Determining the abnormalities Diagnosis of hearing threshold Diagnosis of hearing loss

41. The Brainstem Evoked Response Audiometry (BERA) is an ideal test to interpret the communication of electrical waves from the VIIIth cranial nerve to the brainstem, in reply to capture the sounds given through the ear. The process is also called Auditory Brainstem Response (ABR), Brainstem Auditory Evoked Potential (BAEP), Brainstem Auditory Evoked Response (BAER) and Evoked Response Audiometry (ERA).

42. References https://www.aiishmysore.in/workshops-and-seminars/public-education-pamphlets https://aiishmysore.in/pdf/1_1_HRR_For_Non_Medical_Persons_English.pdf https://aiishmysore.in/pdf/1_1_Remember_and_Care_Check_List_English.pdf https://www.nationwidechildrens.org/specialties/audiology/abr-testing https://emedicine.medscape.com/article/836277-overview https://www.youtube.com/watch?v=ZzMUD0RzNnM

43. http://www.phsa.ca/Documents/HearingTestinginToddlersandOlder.pdf https://www.pediatrics.wisc.edu/education/acute-otitis-media/tympanometry/ https://www.ganeshdiagnostic.com/blog/bera-test-know-everything-in-detail https://www.ashaspeechhearingclinic.com/what-is-bera-hearing-test-and-why-it-is-always-recommended-for-infants/