Ears- General and External Flashcards
what are the 3 types of hearing loss?
conductive: problems that limit movement of sound wave through external & middle ear
sensorineural: damage to hair cells or nerve
mixed: combo of both
what is conductive hearing loss caused by?
- obstructed ear canal
- perforated tympanic membrane
- dislocated ossicle
- OM or SOM
- OE
- otosclerosis or ossicular chain fixation
- congenital
- cholesteatoma
what is sensorineural hearing loss caused by?
- acoustic trauma
- barotrauma
- head trauma
- ototoxic drugs (diuretics, antibiotics, etc)
- infection
- aging
- acoustic neuroma
- sudden SNHL, microvascular
- meniere dz
- vascular dz
- MS
what is tinnitus?
perception of sound in absence of acoustic stimulus
what are the 2 types of tinnitus?
- subjective:audible only to pt, high frequency, damage to hair cells
- objective:rare, can be heard by doc
what can cause subjective tinnitus?
- acoustic trauma
- barotrauma
- CNS tumors
- infections
what can cause objective tinnitus?
- turbulent flow in carotid A or jugular V
- vascular middle ear tumor
what is the work-up for tinnitus?
- history: description of sound, noise of exposure, head trauma, hearing problems, loss of balance, recent dental work, etc.
- PE: ototscopic exam, CN VIII fxn & hearing, check for carotid artery bruits, HTN
- audiology, angiography
what is vertigo?
- nonspecific term describing altered spatial orientation
- most often vestibular, visual or proprioceptive dysfunction
what are the two TYPES of vertigo?
- subjective:pt is moving w/in surroundings
- objective: surroundings are moving around pt
what are the two CLASSIFICATIONS of vertigo?
- true vertigo: sensation of movement
- non-true vertigo: syncope, fainting or sensation of impending fainting
what is true vertigo due to?
most common, asymmetry in vestibular sys (CN8, inner ear, cerebellum)
what are sxs of true vertigo?
- either subjective or objective
- postural instability
- n/v, sweating
- worse when moving head
- nystagmus common
what are further classifications within true vertigo?
peripheral: CN8 or labyrinth
central: cerebellum or vestibular cortex in temporal lobe
how does nystagmus present in peripheral vertigo?central?
peripheral: unidirectional w/fast component towards normal ear, horizontal with rotation
central: any direction, sometimes changes direction
are there other neuro signs in peripheral? central vertigo?
peripheral: absent
central: often, ataxic gait,diplopia, slurred speech, numbness
how is postural stability in peripheral vertigo? central?
peripheral: unidirectional stability, walking preserved
central: severe instability, pt can fall while walking
is there hearing loss in peripheral vertigo? central?
peripheral: may be present
central: absent
what are some causes of central vertigo? what does it include?
lightheadedness: ‘graying out’, suggests hypoperfusion of brain
disequilibrium: w/standing or walking, unsteady w/o dizziness, source may be cerebellum, frontal lobe tumor, etc
miscellaneous: chronic hyperventilation syndrome, new eyeware
work-up or vertigo?
- history: onset sudden or gradual, duration
- PE: general exam, otological exam, extraocular movements, hearing tests, sensory exam to test proprioception, vestibular imbalance
- extra testing for true vertigo: caloric testing (water in ear) & nylene barany maneuver
- extra testing for non-vertigo: orthostatic hypotension, carotid sinus massage, proprioception testing, hyperventilation
sudden onset and vivid memory of episodes are usu due to dz where?
-inner-ear dz
gradual and ill-defined vertigo originates from where?
-CNS, cardiac, & systemic dzs
how long does epidsodic true vertigo last?
-lasts for secs, associated w/head or body position change (BPPV)
vertigo that lasts for minutes can be due to what?
-brain or vascular dz
