ENT Flashcards
what Hz do humans perceive
20-20000
what is the tympanic membrane ratio to the oval window ratio
18:1
what is the resting state of the eustachian tube and what muscles are involved
closed
opened by tensor veli palatini and levator palatini
how many turns are around the modiolus in the inner ear
two and a half
how are the hair cells arranged
in height order
how are the hair cells polarised and depolarised
deflected towards longest - depolarisation
deflected away from the longest - hyper polarisation
what is otoconia
calcium carbonate crystals
what kind of receptors are the taste and smell ones
chemoreceptors
what types of cells do taste buds consist off
receptor cells and support cells
where are taste buds found
tongue in the papillae, palate, epiglottis, pharynx
how long is the half life for receptor cells and what do they synapse with
10 days
synapse with afferent nerve fibres
what are the papillae
finger like
give rough appearance to surface of tongue
types of papillae
filiform - most common has no taste buds
fungiform
vallate
foliate
how is the signal reached from receptor cells to control gustatory areas
signal by CN 7(chorda tympani branch), 9 and 10 via brainstem and thalamus
what are the 5 primary tastes
salty - NaCl sour - acids with free H+ sweet - glucose bitter - lots of stuff umami (meaty or savoury) - amino acids esp glutamate
what is ageusia and what is it caused by
hypoguesia
dysgeusia
loss of taste - nerve damage, inflame
decrease in taste function - chemo, meds
distortion of taste - glossitis, reflux, URTI
what three types of cells does the olfactory mucosa consist of
olfactory receptor cells
supporting cells
basal cells
what is the olfactory rod
ending of each neurone has a thick short dendrite and an expanded end - rod
what do odrants bind to
cilia
what is the life span of olfactory receptors and what happens when they die
2 months
basal calls act as precursors for new olfactory cells
how is smell smelt during quiet breathing
diffusion
what two things does a substance need to be in order to be smelt
volatile and water soluble
what is anosmia and what are the causes
hypsmia
dysosmia
can’t smell - nasal polyps, allergy
decrease smell - paskinsons
distortion of smell
transmission of waves into lymph causing basilar membrane to vibrate
oval window
what does the round window do
acts as a pressure reliever to dampen vibrations after they have had an effect
Na and K conc of perilymph and endolymph and what do they both do
power sensory cells
peri high Na low K
endo low Na high K
what do you do if the eardrum is perforated?
check for infection
if infection present - antibiotics
if no infection then wait
if within a few months the eardrum hasn’t repaired then repair via myringoplasty
what is the treatment plan when a patient comes in with SNHL
confirm SNHL
steroids
then MRI
inflamed bilateral tonsils with grey/white exudates on tonsils
acute tonsillitis
unilateral
uvula pushed to one side
quinsy
grey/white membrane across pharynx
diphtheria
what is a pleomorphic adenoma
who does it occur in
what is its growing track like
benign
common
long history. asymp. slow growing
warthins tumour - what is it associated with - how does it present
benign parotid smoking slow growing painless may be cystic/bilateral
adenoid cystic carcinoma
who
symptoms
malignant parotid frequent perineurial invasions - facial nerve painless slow growing
what rheumatology condition can lead to salivary glad swelling
Sjorgens
how is webners done
centre of head
how is rinnes done
air and bone conduction
each ear
negative means can’t hear anything on that side
what is balls palsy
when does it occur
how does it occur
commonest cause of facial nerve palsy
following URTI
sudden onset
if many nosebleeds and in littles area then what may be the treatment
cauterise - silver
what does a sebaceous cyst look like/produce
superficial
may produce white thick foul smelling fluid
describe a carotid aneurysm
fluctuant
bruit
what is otosclerosis
what are the symptoms
treatment
overgrowth of bony tissue of otic capsule
progressive CHL and tinnitus
if cochlear involved then mixed SNHL and CHL
surgery
list the investigations for the following CHL SNHL Nerves affected blood in ear salivary glands facial fracture sinuses and nose orbital blowout fracture
CT MRI (looking for acoustic neuromas etc) MRI CT US with FNA CT first line for facial fracture CT CT
what drug dries out mouth
amitriptalline
scala media scala tympani scala vestiboli where
endolymph scala media
perilymph tympani vestibuli
difference between endolymph and perilymph
endolymph inside like intracellular (high K low Na)
perilymph outside like extracellular (low K high Na)
what is the otolith
article and saccule of inner ear which has otoconia
list some causes of ototoxicity
gent
carboplantin drugs
what can an orbital blowout fracture lead to
entrapment of muscles - diplopia
facial palsy
treatment for allergic rhinitis
if pregnant or breast feeding?
first line oral antihistamine esp if allergic conjucitivits
nasal polyps/nasal blockage - intranasal corticosteroid (2nd line)
preg - intranasal corticosteroid. oral antihistamine 2nd line or an add on
step up ladder of allergic rhinitis
anti histamine add corticosteroid
if on corticosteroid increase to max dose
if on max dose of corticosteroid then add oral antihistamine
is still symptoms then ipratropium bromide
if still symptoms them oral steroids
histology of tonsils
histology of adenoids
specialised squamous, deep crypts, lymphoid follicles
ciliated pseudo stratified columnar, stratified squamous, deep folds
acute complications of bacterial sore throat
late complications of bacterial sore throat
scarlet fever, quinsy , sinusitis/OM
GN 1-3 weeks after, rheumatic fever 3 weeks after
What kind of toxin does diphtheria release
neurotoxin
cardiotoxin
where are laryngeal nodules in women
bilateral on middle 1/3 to posterior 1/3 of vocal cords
what do laryngeal polyps look like
unilateral and pedunculated
give 80-90% of cerebellopentine angle tumours
vestibular schwonnoma
what is pinna haematoma and how is it treated
collection of blood between the cartilage of the pinna and the overlying skin
aspiration. incision and drainage. pressure dressing
what is an orbital fracture
what is the weakest point
what are the symptoms
impact injury to the globe
infraorbital groove
diplopia, ocular movement affected, bruising, decreased vision, oedema
CHL
SNHL
which kind of temporal bone fracture
longitudinal
transverse
Causes of chronic tonsillitis
strep pyrogens, HI, SA, strep pneumonia
30% beta lactamase producing
give symptoms of adenoidal hyperplasia
obligate mouth breathing
hypo nasal voice
AOM/OME
snoring
give symptoms of tonsillar hyperplasia
snoring
muffled voice
dysphagia
symptoms of otitis external
redness over out ear pain inflam red increase in ear wax can lead to CHL
mild discomfort over head or under cheeks assoc w URTI
severe pain, tenderness and purulent discharge
sinusitis - uncx - don’t give AB - will heal within 14 days
secondary bacterial infection - penicillin (doxycycline)
reasons for giving AB in OME
persistent >3/12
CHL >25db
speech/language issues
investigations for dizziness
otoscope neurological exam BP balance audiometer
treatment for meniers
betahistine
