The cornerstone of audiological testing is the pure-tone audiogram (PTA) which is used as a screening test for hearing loss. An audiometry test is to determine the severity, type, and reason for Hearing Loss. If hearing loss is present, the type and degree of hearing loss will be determined. * How is it being performed? The test will be performed by a qualified MOH-certified Audiologist with the patient seated in a soundproof booth. The Audiologist will be seated outside the sound booth and perform the test using a calibrated audiometer.
This test comprises two parts: The air-conduction thresholds test and the bone-conduction thresholds test. For the air-conduction test, the test signals are delivered through a pair of headphones or inserted earphones. For the bone conduction test, the test signals are delivered through a bone vibrator which conducts the sound directly to the inner ear. Test signals ranged from 250 Hz to 8 KHz and the patients are required to respond by pressing a response button when he/she hears the test signals. Along with this in Audiometry MCL and UCL levels are also measured. If required Audiologist will do Speech discrimination scoring (SDS) and Speech Reception Threshold (SRT) also. The test will take about 20 to 25 minutes and the results will provide ear-specific and frequency-specific information on the degree and type of hearing loss. A comprehensive hearing test report indicating the type and degree of the hearing impairment will be given and explained at the end of the assessment session.
FFA/BOA (Free Field Audiometry/Behavioural Observation Audiometry): This test is also called play audiometry in which we estimate the threshold by giving the sound through speakers and observing the reflex of the client. It can be used in babies for diagnosing estimated threshold pre-fitting thresholds or aided thresholds post-hearing aid fitting. It is a commonly used tool for getting an Aided hearing response after fitting the hearing aid. But the Automated tests i.e. ABR & ASSR are more accurate in identifying Hearing loss in pediatric or difficult-to-test clients.
Puretone Audiometry allows us to evaluate the softest sound one can detect but it does not provide any information about one’s ability to hear and understand speech. A hearing test using speech stimulus will help to find out the person's ability to hear and understand speech and this test is called Speech Audiometry. Speech test helps in different aspects: - * To cross-check the pure-tone hearing thresholds * Help in hearing aid selection * To assess the suitability of various implant solutions such as - Cochlear implants - Bone Anchored Hearing Aid - Middle Ear Implant * Help in identifying functional hearing loss. How is the speech test being performed? The test is performed by a qualified Audiologist with the patient seated in a calibrated, soundproof room. Live or recorded speech stimuli are delivered through either headphones or speakers. The patient is required to repeat the speech stimulus they hear. There are two different speech tests:
SRT: Speech Reception Threshold helps to determine the lowest level a patient can hear and repeat two-syllable words 50% of the time. SDT: Speech Discrimination Test This is to determine the speech discrimination ability of an individual. The test is done at a suprathreshold level (about 25 to 30 dB above SRT) and is calculated in terms of percentage.