Ear Disorders 1 Flashcards
what landmark separates the inner and outer ear?
typmanic membrane
Ear Anatomy
Purpose of Pinna/Auricle
funnels sound down auditory canal
Ear Anatomy
purpose of auditory canal or external auditory meatus
carries sound to the TM
Ear Anatomy
purpose of TM
vibrates from sound waves and transfers the movement to the ossicles
Ear Anatomy
purpose of the malleus, incus, stapes
pass sound vibrations into the fluid of the cochlea through the oval window
Ear Anatomy
purpose of the cochlea
part of auditory labyrinth which connects to vestibulocochlear nerve CN VIII
Ear Anatomy
purpose of eustachian tubes
links the cavity of the middle ear to the nasal cavity and provides a route to equalize air pressure between the middle ear and the atmosphere
Audiometry
purpose
to test for hearing loss
Audiometry
how is intensity measured
decibles
whisper = 20 dB
concert= 120 dB
Audiometry
how is tone measured
cycles per sec (cps) or Hertz (Hz)
high pitched tones = high Hz values
Audiometry
normal range of human hearing (Hz)
20 to 20,000 Hz
Tympanometry
purpose
- compliance (movement) ofear structures
- measures mobility of the ear drum and small bones in the middle ear
Tympanometry
absolute contraindications
3
- base skull fracture
- head trauma
- recent ear surgery
Hearing Loss
Describe weber test and results
- place 512 Hz tuning fork midline
- Conductive: sound radiates to bad ear
- Sensorineural: sound radiates to good ear
Hearing Loss
describe rinne test and results
- alternate 512 Hz on mastoid bone and in front of ear
- conductive loss: BC > AC
- sensorineural loss: AC > BC
Hearing Loss
what causes conductive hearing loss?
results from external or middle ear dysfunction
Hearing Loss
4 mechanisms of conductive impairment
- obstruction
- mass loading
- stiffness
- discontinuity
Hearing Loss
risk factors for conductive loss
5
- cerumen impaction
- transient eustachian tube dysfunction
- chronic ear infections
- trauma
- otosclerosis
Hearing Loss
which type of loss can be treated w/ meds or surgery?
conductive
Hearing Loss
describe sensorineural loss
- deterioration of cochlea usually due to loss of hair cells from the organ of Corti
Hearing Loss
most common type of sensorineural hearing loss
Presbycusis
Hearing Loss
Risk Factors for Sensorineural Loss
4
- excessive noise exposure
- head trauma
- systemic diseases
- family hx/genetics
Presbycusis
describe
gradually progressing high frequency loss w/ advanced age
Presbycusis
type of loss
sensorineural
Presbycusis
diagnostic testing
- weber test
- rinne test
- audiometry
Presbycusis
tx
3 components
- not correctable w/ medical therapy (prevention is key)
- hearing amplification
- cochlear implant
Presbycusis
screening recommendations
3 components
- age > 65 yo
- prior exposure to high noise levels
- repeat every few years
Presbycusis
when to refer?
refer any new sensorineural hearing loss to audiologist unless it is easily treatable (i.e. OM)
Noise Trauma Induced Hearing Loss
what must prolonged sound exposure be above?
typically > 85 dB
Noise Trauma Induced Hearing Loss
what type of hearing is first to be lost? what about with prolonged exposures?
- high frequency
- speech frequencies
Noise Trauma Induced Hearing Loss
Examples of noise trauma
3
- heavy machinery
- weapons
- excessively loud music
Noise Trauma Induced Hearing Loss
prevention
3
- monitoring workplace noise levels
- ear plugs
- customized earmuffs
Physical Trauma Induced Hearing Loss
what part of ear is impacted?
inner ear
Physical Trauma Induced Hearing Loss
Examples of things that could cause?
3
- airbag deployment
- Concussion
- Skull fracture
Ototoxicity
describe
- hearing loss from ototoxic substances which affect auditory and vestibular systems
Ototoxicity
most common meds
3
- aminoglycosides
- loop diuretics
- neoplasm meds (cisplatin)
Ototoxicity
what to do with pts who have existing hearing loss and need ototoxic meds?
2
- monitor closely
- weigh risks/beneifts of drug choice
Sudden Sensory Hearing Loss
describe
idiopathic sudden unilateral hearing loss
Sudden Sensory Hearing Loss
typical age of onset?
> 20 y/o
Sudden Sensory Hearing Loss
tx
- corticosteroid use increases chances of recovery
- prednisone 1 mg/kg/day then taper for 10d
Systemic Disorders Inducing Hearing Loss
describe
- bilateral loss
- hearing level can fluctuate (recovery/deterioration/remission/relapse)
- gradual progression
Systemic Disorders Inducing Hearing Loss
can have what in addition to hearing loss?
2
vestibular dysfunction (disequilibrium, postural instability)
Systemic Disorders Inducing Hearing Loss
Examples of conditions
3
- Systemic Lupus Erythematosus
- Granulomatosis w/ polyangitis
- Cogan syndrome
Systemic Disorders Inducing Hearing Loss
tx
corticosteroids w/ taper
Tinnitus
can accompany?
hearing loss
Tinnitus
sensation of sound in the absence of?
exogenous sound source
Tinnitus
etiology
4
- can be idiopathic
- from meds (ASA, NSAIDs)
- vascular lesions
- cochlear lesions
Tinnitus
describe bilateral damage
3 components
- more common
- damage to conductive hearing system
- can be environmental or systemic
Tinnitus
describe unilateral tinnitus
4
- tympanic membrane damage
- recurrent unilateral ear infections
- ossicle damage
- trauma
Tinnitus
describe sx
2
- ringing in ears
- difficulty hearing in social situations
Tinnitus
severe sx
3 components
- insomnia
- inability to concentrate
- psychological distress (anxiety, annoyance, frustration, loss of control)
Tinnitus
describe pulsatile tinnitus
can hear own heartbeat
Tinnitus
etiologies of pulsatile tinnitus
2
- conductive hearing loss
- vascular abnormalities (glomus tumor, venous sinus stenosis, varotid vaso-occlusive disease, AV malformation, aneurysm)
Tinnitus
dx non-pulsatile
2 components
- audiometry to r/o hearing loss
- if unilateral hearing loss w/out cause: MRI to assess for cochlear lesion (vestibular schwannoma)
Tinnitus
dx pulsatile
2 components
- MRA/MRV
- temporal bone CT
Tinnitus
tx
4 components
- avoidance of exposure to excessive noise, ototoxic agents, and other factors causing cochlear damage
- masking tinnitus w/ music or amplification of other sounds
- habituation techniques (tinnitus retraining therapy)
- PO anti-depressants (nortriptyline 50mg PO at bedtime)
Tinnitus
why give nortriptyline at night?
to help with insomnia
Hyperacusis
describe
excessive sensitivity to sound
Hyperacusis
Risk factors
4
- ear disease
- noise trauma
- migraines
- underlying psychological disease
Hyperacusis
describe recruitment as it pertains to hyperacusis
abnormal senstivity to loud sounds despite reduced sensitivity to soft sounds
Hyperacusis
tx in pts w/ normal hearing
- earplugs in noisy environments
- habituation (slowly introduce to noise)
Hyperacusis
tx in pts w/ hearing devices
compression circuitry to avoid overamplification
Vertigo
cardinal sx of which type of disease state?
vestibular disease
Vertigo
sx
- spinning sensation
- sensation of tumbling/falling forward/backward
- sensation of motion when there is no motion
Vertigo
important to distinguish this from?
- imbalance
- syncope
- light-headedness
Vertigo
describe peripheral disease
4 components
- onset is sudden
- associated w/ tinnitus & hearing loss
- +/- horizontal nystagmus
- vertigo may be more intense
Vertigo
describe central vertigo
3 components
- onset is gradual
- no associated auditory sx
- vertigo is not as intense
Vertigo
how to evaluate
4
- audiogram
- electronystamography (ENG)
- videonystagmography (VNG)
- MRI Head
Meniere Syndrome
pathophys
excess endolymph results in increased pressure w/in the semicircular canals
Meniere Syndrome
classic syndrome
episodic vertigo w/ discrete spells lasting 10 min to several hours
Meniere Syndrome
additional sx
5
- sx wax and wane
- unilateral aural fullness (pressure in ear)
- tinnitus (low tone/blowing sound)
- fluctuating low-frequency sensorineural hearing loss
- vertigo
Meniere Syndrome
PE findings
2 components
- normal
- +/- nystagmus or induced vertigo/nausea with pneumo-otoscopy
Meniere Syndrome
what would audiometry at time of attack show?
low-frequency sensorineural loss
Meniere Syndrome
tx
- refer to otolaryngologist
- diuretic (acetazolamide)
- Na+ restriction
Meniere Syndrome
tx for sx relief of acute attacks
2
- meclizine
- diazepam
Meniere Syndrome
tx options for refractory disease
3
- glucocorticoid or gentamicin infections into middle ear
- non-ablative surgical options (decompression, shunting of endolymphatic sac)
- full ablative procedure (labyrinthectomy, vestibular nerve section)
Labrynthitis
cause
idiopathic, sometimes linked to recent infection (URI)
Labrynthitis
hallmark of the condition
acute onset of continuous, severe vertigo lasting several days to a week accompanied by tinnitus and hearing loss
Labrynthitis
sx
4 components
- nausea, vomiting
- desire to remain immobile
- recovery period of several wks (improving vertigo)
- hearing may return to normal or stay impaired
Labrynthitis
what is this classified as if there is no associated hearing loss?
vestibular neuritis
Labrynthitis
PE Exam findings
4 components
- nystagmus and sense of body motion to opposite side
- falling and past pointing to the affected side
- vestibular paresis unilaterally
- rapid-head-impulse test as tolerated
Labrynthitis
dx
MRI w/ contrast
Labrynthitis
what will MRI show
enhancement of 8th nerve or the menbranous labyrinth
Labrynthitis
Tx
3 components
- abx if pt is febrile or has sx of bacterial infection
- vestibular suppressants during acute phase of attack (diazepam, meclizine)
- sx reduction (anti-histamines, promethazine, scopolamine)
Benign Paroxysmal Positional Vertigo
pathophys
- migration of inner ear otoliths (calcific particles) to the posterior semicircular canal
- the otoliths amplify any movement in the plane of the canal, resulting in brief episodes of vertigo following changes in head position
Benign Paroxysmal Positional Vertigo
common in who?
people over 60 y/o
Benign Paroxysmal Positional Vertigo
classic presentation
recurrent spells of vertigo, lasting only a few minutes, associated with changes in head position
ex: rolling over in bed, looking up
Benign Paroxysmal Positional Vertigo
additional sx
4
- intermittent dizziness (10-15s latency period followed by 60s of dizziness)
- “entire room spins”
- imbalance for several hours
- nausea
Benign Paroxysmal Positional Vertigo
pertenient negatives
3
no associated…
1. HAs
2. hearing loss
3. focal neurologic sx
Benign Paroxysmal Positional Vertigo
only abnormal PE finding
nystagmus
Benign Paroxysmal Positional Vertigo
dx studies
2
- recurrent cases warrant head MRI
- some CNS disorders can mimic BPPV
Benign Paroxysmal Positional Vertigo
tx
- Epley maneuver (PT or pt can do to themselves if recurrent)
- often resolves spontaneously or does not require tx
Otosclerosis
pathophys
progressive disease affecting bony otic capsule
Otosclerosis
where is lesion typically located?
stapes
Otosclerosis
what does the lesion cause?
- decreased passage of sound through the ossicular chain
- conductive hearing loss
Otosclerosis
tx
- hearing aids
- stapedectomy (replacement of stapes w/ prosthetic)
Otosclerosis
what can happen if cochlea is involved?
permanent hearing loss
Middle Ear Trauma –> TM Perforation
causes of TM perf from trauma
6
- barotrauma
- acoustic trauma
- head trauma
- otitis media
- eustachian tube dysfunction
- foreign objects
Middle Ear Trauma –> TM Perforation
sx
6
- otorrhea (clear, bloody, purulent)
- +/- ear pain w/ sudden relief
- conductive hearing loss
- tinnitus
- vertigo
- nausea/vomiting
Middle Ear Trauma –> TM Perforation
PE Findings
conductive hearing loss confirmed w/ weber and rinne tests
Middle Ear Trauma –> TM Perforation
what PE exam to avoid? why?
- pneumatic otoscopy
- can push air into otic capsule underlying the injury
Middle Ear Trauma –> TM Perforation
dx
- based on otoscopic exam
- conductive hearing loss
Middle Ear Trauma –> TM Perforation
tx
- small ones: heal spontaneously within 4 wks
- water precautions: cotton ball w/ jelly in ear when around water
- abx drops (ofloxacin)
- f/u with audiology
- ENT referral
Middle Ear Trauma –> TM Perforation
criteria for ENT referral
3
- Recurrent otitis media (>2 episodes in 6 mo)
- persistent hearing loss (> 1-2 wks post infection)
- chronic tympanic membrance perforation (>4 wks)
Middle Ear Trauma –> TM Perforation
complications
4
- persistent perforation
- cholesteatoma
- hearing loss
- recurring infections
Impact Injury/Explosive Acoustic Trauma
describe
conductive hearing loss of >30 dB for 3+ mo after trauma
Impact Injury/Explosive Acoustic Trauma
what should you suspect if patient has this?
ossicular chain disruption
Impact Injury/Explosive Acoustic Trauma
tx
middle ear exploration w/ reconstruction of ossicular chain
