Physiology and Clinical Apsects of Hearing and Balance Flashcards
What is the function of the Eustachian tube?
Equalisation of pressure and drainage of the middle ear
Which investigations can be used to assess hearing and middle ear function?
Clinical testing, tuning fork tests, audiometry, tympanometry and objective testing
Which two hearing tests are tuning fork tests?
Webber and Rinne’s
What types of audiometry are there?
Pure tone, visual reinforcement, play audiometry and tympanometry
What does pure tone audiometry measure?
It determines the faintest tones a person can hear at selected pitches (frequencies)
In which age group Is visual reinforcement audiometry used?
6months - 3yrs
How does otoacoustics emissions testing work
When the cochlea is stimulated by sound and the outer hair cells vibrate and emit a sound that travels back into the middle ear
How does Auditory Brainstem Response (ABR) work?
Electrodes are pasted onto the head and record brain activity in response to sound - gives information about the inner ear and brain pathways for hearing
How does tympanometry work?
It pushes air into the ear canal making the tympanic membrane move back and forth (tests the mobility of the eardrum) - can detect perforation of the eardrum, fluid in the middle ear and wax blocking the ear canal
What are the management options for hearing loss?
Surgery of outer/middle ear, sound amplification and direct stimulus of cochlear nerve cells
What type of aids are there for hearing loss?
Open fit hearing aid, bone anchored hearing aid (BAHA), middle ear implant and cochlear implant
What does the vestibule-ocular reflex do?
It stabilises the gaze by moving eyes in order to compensate for head and body movement - fixes image on retina for clear sight
Which conditions of the inner ear affect balance?
Benign Paroxysmal Positional Vertigo, Vestibular Neuritis and Meniere’s disease
