Hearing loss Flashcards
a defect in which part of the hearing pathway causes CHL
outer ear
middle ear
a defect in which part of the hearing pathway causes SNHL
inner ear
what are the different classifications of hearing loss
CHL
SNHL - cochlear or retrocochlear
mixed
what feature on an audiogram would suggest CHL
air bone gap
list causes of CHL in the ear canal
atresia
otitis externa
ear wax
stenosis
list causes of CHL in the middle ear
acute otitis media otitis media with effusion (glue ear) cholesteatoma tympanic membrane perforation ossicular chain abnormalities otosclerosis
what is glue ear
otitis media with effusion
describe features of otitis media with effusion
more common in children
Eustachian tube dysfunction
straw coloured fluid
causes of otitis media with effusion in adults
rhinosinusitis
nasopharyngeal carcinoma / lymphoma
management of otitis media with effusion
grommets
further investigations if adult presentation
features of otitis media with effusion on tympanogram and audiogram
flat tympanogram
CHL - air bone gap
clinical signs of otitis media with effusion on otoscope
retracted membrane
why is myringotomy not effective for otitis media with effusion
the membrane would heal very quickly and fluid would reaccumulate
how long do grommets usually last for otitis media with effusion
9-12 months
acute otitis media is more common in children/adults
children
what is acute otitis media associated with
glue ear
URTI
acute otitis media is usually viral/bacterial
viral
therefore do not treat with antibiotics until after 3 days
clinical signs of acute otitis media on otoscopy
bulging membrane - pars tensa
chronic suppurative otitis media is an old term to encompass which conditions
cholesteatoma
perforated tympanic membrane
what is a cholesteatoma
collection of keratin in the middle ear
clinical signs of cholesteatoma on otoscopy
retracted membrane
perforation
keratinous debris at pars tensa or flaccida
erosion of ossicles
complications of acute otitis media and cholesteatoma
medially –> SNHL, tinnitus, vertigo, facial palsy
superiorly –> meningitis, brain abscess
posteriorly –> venous sinus thrombosis
what is otosclerosis
gradual onset CHL with normal examination
fixation of stapes footplate
features of otosclerosis
CHL
F>M
FH - inherited
worsens during pregnancy
management of otosclerosis
conservative
hearing aids
fixation of stapes footplate
stapedectomy
trauma can cause CHL + SNHL, true or false
true
what is haemotympanum
blood collection behind the membrane
what is battle’s sign
bruising behind the ear indicative of base of skull #
symptoms and signs of BOS #
Hearing loss CSF leak facial palsy battle sign bilateral periorbital bruising
causes of acquired SNHL
presbyacusis noise induced drug induced vestibular schwannoma - CPA Menieres trauma + BOS # inflammatory autoimmune meningioma
what is presbyacusis
age related high frequency sensorineural hearing loss
describe features of noise induced hearing loss
classical dip ay 4000Hz aka Cahart’s notch
causes of drug induced hearing loss
aminoglycoside - gentamicin
chemotherapy - cisplatin, vincristine
aspirin overdose
diuretics - furosemide
peri/endolymph is found in the bony labyrinth
perilymph
peri/endolymph is found in the membranous labyrinth
endolymph
what happens in profound SNHL
loss of hair cells in the organ of corti
list chromosomal congenital causes of SNHL
Connexin 26 GJB2 - most common deafness Waardenburg's - AD Stickler - AD Usher's - AR Pendred's - AR
list non-genetic congenital causes of SNHL
rubella VZV HIV CMV Streptococcus drugs/alcohol misuse
short noise exposure hearing loss is reversible, true or false
true
causes of inflammatory SNHL
fibrosis of the cochlear duct from: meningitis labyrinthitis mumps, measles syphilis
in CHL there is/not an air bone gap
there is an air bone gap
in SNHL there is.not an air bone gap
there is not an air bone gap
list autoimmune causes of SNHL
RA
GPA
sarcoidosis
Menieres has high/low frequency hearing loss
low frequency
when would you use an open fitting hearing aid
for milder degrees of hearing loss
how do cochlear implants work
electrically stimulating neural structures in the cochlea which is then transmitted to the brain and perceived as sound
when would you use cochlear implants
severe - profound SNHL
management of ear wax build up
olive oil
sodium bicarbonate solution
ear syringing
