Otology Flashcards
what is the results of rinne’s test in normal hearing?
air conduction>bone conduction (test ‘positive’)
what is the results of rinne’s test in conductive hearing loss?
bone conduction>air conduction (test ‘negative’)
what is the results of rinne’s test in sensorineural hearing loss?
air conduction>bone conduction (test ‘positive’)
but sound stops much earlier than normal hearing
what is conductive hearing loss?
something inhibiting the passage of sound waves from the ear canal, through the middle ear apparatus and into the cochlea
what is Sensorineural hearing loss?
root cause lies in the inner ear or sensory organ (cochlea and associated structures) or the vestibulocochlear nerve
describe the Weber’s test?
vibrating tuning fork is placed in the middle of the forehead, and compare both ears
what is the results of Weber’s test in normal hearing?
sound heard equally in both sides
what is the results of Weber’s test in sensorineural hearing loss?
hearing loss right ear. left>right (test ‘lateralises to left’)
ie normal ear hears the tuning fork louder
what is the results of Weber’s test in conductive hearing loss?
hearing loss right ear. right>left (test ‘lateralises to right’)
ie defective ear hears the tuning fork louder
what is an audiogram?
a graph that shows the audible threshold for standardized frequencies as measured by an audiometer
what should a normal audiogram show?
Ideally the audiogram would show a straight line above the standardised curve that represents ‘normal’ hearing, but in practice everyone is slightly different, and small variations are considered normal
what is a tympanometry?
examination used to test the condition of the middle ear and mobility of the tympanic membrane by creating variations of air pressure in the ear canal.
what does type A mean in tympanometry?
normal, Tympanogram shows maximum peak compliance (shaped like a teepee)
what does type B mean in tympanometry?
tympanograms are a flat line, fluid or infection behind the ear drum, tympanic membrane immobile
what does type C mean in tympanometry?
shaped like a teepee, but shifted negatively on the graph
indicates negative pressure in the middle ear space, often consistent with sinus or allergy congestion
what is Auricular haematoma?
external portion of the ear is hit and develops a blood clot or other collection of fluid under the perichondrium
what is Otitis externa?
common ear infection that causes inflammation (redness and swelling) of the external ear canal