Audiometers
An audiometer is a subjective device that is used to evaluate the hearing threshold of a person. An audiologist or other trained personnel uses an audiometer together with special audiometric testing techniques to determine the hearing threshold and to identify as well as quantify the degree of hearing loss of a person. From these results the appropriate referral for medical treatment or possible hearing aid fitting can be prescribed. With the audiometer tones of different frequencies .....
Tympanometry
Tympanometry is an objective measurement which provides one way of diagnosing and monitoring problems in the middle ear. Tympanometry helps to find and diagnose disorders that may lead to or have already caused a hearing loss. The tympanogram in conjunction with the audiogram helps to determine whether medical treatment is required or hearing aids should be provided. The full immittance measurement battery including the tympanometry test, the evaluation of the function of the interaural muscles....
ABR Testing
An ABR (Auditory Brainstem Response) test measures the neural activity of a large portion of the auditory nerve pathway. ABR recording can be applied for diagnostic or screening hearing tests to identify hearing problems which can be related to inner ear or subcortical auditory structures. An ABR hearing test analyzes the neural activity from the auditory nerve to the lower brainstem. Electrodes pick up the electrical activity from surface of the skin, including the activity of the brain, muscle activities (myogenic noise) and electromagnetic interferences. The ABR device analyzes these activities by looking for specific patterns, which indicate a normal transduction of sounds into electrical activity and its processing by the auditory brainstem. Various lesions on the auditory pathway change the ability of the cochlea to convert sound waves into neural stimuli and allow...
OAE Testing
Otoacoustic emissions (OAE) are very soft sounds which are generated in the cochlea (inner ear) in response to a sound stimulus. The hair cells in the cochlea are set into vibration when we hear sounds and transform those mechanical movements into neural signals. In response to the stimulus, an echo is generated by the hair cells and these vibrations are transmitted as soft sounds from the inner ear, through the middle ear, to the outer ear. Studies have proven that OAEs disappear when the inner ear has been damaged (hearing loss of more than 25-30 decibels), that is why OAEs are often used to determine the health of the inner ear. An OAE screening can also detect conductive hearing loss. If the middle ear is blocked, the very quiet sounds will not be able to get through from the inner ear to the outer ear.
