Features and Uses of screening Audiometers in Visual Reinforced Audiometry Testing

Visual Reinforced Audiometry (VRA) test is performed to measure hearing sensitivity and hearing loss in patients who are unable to undergo traditional testing due to developmental limitations, or aging. Typically, it is performed in children aged six months to three years of age. The audiologist uses a machine called a screening audiometer to test a child’s hearing threshold levels. Standard pure tone audiometers use headphones and a feedback button, so these cannot be used on infants and young children. On the other hand, visual audiometer makes use of video animations or lighted toys placed at 90 degrees on each side of the child, and trains them to look toward the direction of the sound. 

  Aim of the visual reinforced audiometry test is to determine the binaural hearing threshold in the child for a given sound stimulus, i.e. a single frequency. The frequency used is often 500 Hz, 1 KHz, 2 KHz, and 4 KHz. If the child cooperates and their concentration is sufficient then the test can be performed for other frequencies as well. Speakers emit sounds at specific frequency and volume played, while the audiologist observes characteristics, scope, intensity, and frequency of the child’s responses. Visual reinforced audiometry test is performed on a changing table, which is placed in a calibration-free field. For older children, the test is performed in the parent’s lap, or on a baby carrier.   

  

Conditioning the child for testing   

As the name suggests, visual reinforced audiometry test is performed by reinforcing the presentation of a visual target. The child’s response to VRA is known as conditional response, which means that the child associates the presentation of the sound stimulus with a reward. This is in the form of visual target that they receive upon performing a head turn towards the target. But, instead of reward, it is actually a visual reinforcer that reinforces the child’s conditioned head-turn response throughout visual reinforced audiometry testing. Successful conditioning can be effective, and is the starting point for testing. A second tester should encourage the child to look towards the visual reinforcer with appropriate level of social enforcement, such as smiling, clapping, pointing, and showing excitement.   

 

If the child performs an independent head turn towards the visual display, a reinforcer should then be displayed. But if the child doesn’t, then the reinforcer should be displayed as part of the ongoing conditioning. If the child appears to have lost association between the sound stimulus and the visual reinforcer, then it may become necessary to recondition them. Proper care needs to be exercised here by the audiologist to ascertain whether this is due to loss of conditioning, due to the sound being below the child’s threshold, and therefore is inaudible to him or her.   

  

Screening audiometer to determine measurable hearing loss   

The audiologist may also use a screening audiometer to determine if there is any measurable hearing loss. Many screening audiometers are preset with an automatic threshold hearing levels so that initial screening can be performed quickly. A screening audiometer typically uses pure tone audiometry to perform basic air conduction test. It is used to indicate if there is a hearing loss, and may indicate standard threshold shifts over time. If the screening test indicates a moderate to severe loss of hearing, a test using a diagnostic audiometer may be required, that will indicate specifically whether a hearing loss has occurred. That way, a screening audiometer tells if there is a hearing issue, while a diagnostic audiometer will identify the hearing issue. Based on the results of the screening audiometer, an appropriate referral for medical treatment or possible hearing aid fitting can be prescribed.   

  

Audiometers from the world’s top brands   

If you are looking for the best quality screening audiometers and visual reinforced audiometry equipment for your practice, then Sonic Equipment has some of the best devices from the world’s top brands that you can order. Maico MA28 screening audiometer available at Sonic Equipment is capable of air and bone conduction measurements, be it in the clinic or the field. The portable device is designed to be lightweight and sturdy. Its integrated handle and storage compartment make transportation even easier while protecting all of your accessories necessary for hearing.   

  

Flex VRA takes flexibility to the next level when it comes to equipment required for visual reinforced audiometry testing. The device offers multiple stimulus options, and complete volume control from the remote, touchscreen controls, and distract mode to be utilised during OAE, tympanometry, and otoscopy. Flex VRA delivers audiologists the most comprehensive visual reinforcement audiometry system available. MedRx VRA has integrated National Acoustic Laboratories technology, and offers visual reinforced audiometry as an add-on to the new MedRx Studio software. The clinician can adjust level, frequency, presentation ear, and presentation and visual rewarding from MedRx iVRA iOS app.