Hearing Assessment Flashcards
What is a tuning fork used for?
Establish the probable presence or absence of a hearing loss with a significant conductive component.
Early and general - when audiometry is not available.
What is pure tone audiometry?
Measuring hearing acuity for variations in sound intensity and frequency.
It uses an audiometer which produces sound of varying intensity and frequency.
The audiogram is where the hearing thresholds are plotted.
What is normal hearing range?
0-20dB
What assesses hearing abilities other than detection? What does it include?
Central processing assessment. Includes sound localization, filtered speech and speech in noise. Non-verbal and verbal tests.
What examination tests the middle ear and eardrum and the conduction bones? What does it involve?
Tympanometry tests the condition of the middle ear and mobility of the eardrum and the conduction bones. This is done by creating variations of air pressure in the ear canal.
What are the results of tympanometry?
A- Normal
C - Negative middle ear pressure
B - Middle ear effusion/perforation of tympanic membrane/eustachian tube dysfunction/occluded ear canal
What is used to test newborn hearing and how does it work?
Otoacustic emission - the normal cochlea produces low intensity sounds called OAEs made by the expansion and contraction of outer hair cells. Also used to monitor hearing loss.
What are some types of evoked potentials we can measure?
Electrocochleography - 0.2-4ms electrical activity from the cochlea and eighth nerve evoked by clicks or t burst.
Auditory brainstem response (ABR) - 1.5-10ms electrical activity from eighth nerve and brainstem nuclei and tracts evoked by clicks.
Late responses (80-500+ms) electrical activity from primary auditory and association cortex. Evoked by tone burst and oddball paradigm.
What could cortical potentials also be affected by?
Neurological conditions or processing problems.
