Otolaryngology Flashcards
AOM: presentation, Hx, PEx, mgmt
Presentation: fever, irritability, ear tugging, recent URTI.
Hx: Duration of illness, ear d/c, previous ear infections, oral intake.
PEx: bulging TM, yellow opacity.
No investigations.
Mgmt: Analgesics and antipyretics. majority are self-limited. If >2 yrs and uncomplicated AOM, can watch and wait for 48-72 hrs and if no resolution, give amox.
If >2yrs: 40 mg/kg amox x5 days, <2 yrs, x20d.
Tx of + consequences of current AOM/prolonged OME
Recurrent: 3 episodes of AOM in 6 months or 4 in 12.
Can give abx prophylaxis.
Do tympanogram/pure audiogram to r/o hearing loss/language development problem.
May require hearing aids.
Indications for ventilation tubes:
1) Prolonged (>3 mo) OME w/ documented hearing loss.
2) Prolonged OME in kids with developmental difficulties.
Otitis externa: presentation, Hx, PEx, Mgmt
Presentation: ear pain, plugging.
Hx: other ear symptoms (hearing loss, tinnitus, vertigo, aural fullness, otorrhea), fever, recent URTI, Hx DM (assoc increased risk of infxn to ear canal–> malignant otitis externa!), trauma, recent swimming, barotrauma. Previous episodes.
PEx: extreme pain with manipulation of pinna and external auditory canal. Inflamed early canal (swollen with white debris).
No investigations but do C+S if no response to initial tx.
Mgmt: Aural toilet (suction/remove d/c, don't use water b/c makes infection worse). Topical drops: Ciprodex (tx's pseudomonas, staph aureus), keep ear dry, avoid Q tips, use ear wick for severely swollen canal.
Differentiate between conductive hearing loss and sensorineural hearing loss
conductive: problem in the middle or outer ear.
Sensorineural: damage to hair cells, cochlear nerve or CNS.
Mixed: both conductive and sensorineural possible
How does the Rinne test work?
Place tuning fork on mastoid, once the pt no longer hears the sound, move the tuning fork to air in from of auditory canal until pt no longer hears sound.
Normal hearing: air conduction > bone conduction. I.e. hear sound at pinna after they can no longer hear at mastoid.
Conductive loss: bone conduction > air conduction. Unable to hear post-mastoid.
Sensorineural: bone and air conduction both equally decreased.
How does the Weber test work?
Place tuning fork in the middle of the forehead/top of the head (in contact with bone) -> ask which ear the sound is heard louder in.
Normal/symmetric hearing loss: equal both ears.
Defective ear hears louder: conductive hearing loss.
Normal ear hears louder: sensorineural loss in quiet ear.
Important questions on history for pt complaining of hearing loss.
Ear symptoms: progressive vs fluctuating hearing loss, unilateral vs bilateral loss, tinnitus, vertigo, aural fullness, otalgia, otorrhea.
Trauma, previous surgery, recent infections.
Ototoxic meds (gentamicin, cisplatin).
Noise exposure.
FamHx of hearing loss.
PEx for hearing loss (2)
Clinical voice test.
Weber and Rinne.
Describe how to interpret an audiogram
X axis = frequency, Y axis is dB lost.
Plot air conduction response (O=R, X=L) and bone conduction response ( [ = R, ] = L) for each ear.
If air and bone conduction curves decrease together for same ear: sensorineural hearing loss.
If air conduction drops > bone conduction: conductive loss for that ear.
When conducting test, need to mask one ear to ensure sound is heard only by other ear (often play white noise).
DDx for conductive hearing loss
External canal:
1) Cerumen impaction,
2) Severe otitis externa,
3) Stenosis of canal,
4) Masses.
Middle ear:
1) Otitis media (acute or chronic),
2) Tympanic perforation,
3) Cholesteatoma,
4) Otosclerosis: F>M, worse with pregnancy, does not cause scarring. Relatively uncommon (fluoridated H2O protective),
5) Ossicular fixation: ask about hx infxns in childhood.
6) ossicular discontinuity.
DDx for sensorineural hearing loss
1) Noise induced: hx noise exposure, progressively affecting lower and higher frequencies.
2) Presbycusis: loss of high frequency sounds.
3) Genetic causes.
4) Ototoxicity: e.g. cytotoxic meds/anti-metabolites, aminoglycosides.
5) Acoustic neuroma: suspect if sudden hearing loss, start steroids urgently.
6) Vestibular schwannoma.
Mgmt of conductive hearing loss
Ongoing observation.
Trial of amplification (hearing aid).
Surgical: stapedotomy if air-bone gap >30dB (however, risk of losing all hearing and balance fxn).
Mgmt of sensorineural hearing loss
Ongoing observation, hearing protection, trial of amplification (aid)
What is an acoustic neuroma, how is it managed?
Schwannoma of the vestibular portion of CN 8.
Presents with acute sensorineural hearing loss or tinnitus (if a pt presents like this, consider neuroma until proven otherwise).
If elderly, unilateral tinnitus or SNHL = neuroma until proven otherwise.
Start steroids ASAP for acute SNHL, do MRI to look for neuroma.
Surgically excise tumor
Define tinnitus
auditory perception in the absence of acoustic stimuli. Loss of input to neurons in central auditory pathways –> abnormal firing.
What are the RF for tinnitus?
Loud noise exposure, older age, male, smoking history, CVD.
Most commonly associated with SNHL.
If elderly person presenting with new tinnitus/SNHL, r/o acoustic neuroma.
Definition of vertigo
Illusion of rotational, liner or tilting movement of self or environment.
Difference between peripheral and central vertigo.
Peripheral = inner ear problem. Presents with otolgic symptoms (hearing loss, tinnitus, aural pressure, pain discharge), nystagmus and vertigo last for a couple of weeks only.
Central = CNS problem. neurological symptoms common. Pt will have persistent nystagmus and vertigo.
Etiology of non-vertiginous dizziness
Organic: cardiac, vasovagal, hypoTN, anemia, visual impairment.
Functional: depression, anxiety, panic, personality disorder
Important Q’s on Hx for vertigo
Duration, otologic symptoms (hearing loss, tinnitus, aural pressure, pain, discharge), aggravating and alleviating factors (e.g. head position), head trauma, n/v.
Important parts of PEx for vertigo
ENT exam.
Neuro-otologic exam: spontaneous or gaze-evoked nystagmus, CN exam, cerebellar testing + Romberg, gait, Fukuda step test, head thrust or shake.
Neurologic exam.
Describe benign paroxysmal positional vertigo
Acute attacks of transient rotatory vertigo that lasts for seconds to minutes.
Initiated by certain head positions.
Caused by ‘canalithiasis,’ i.e. migration of free floating otoliths in the endolymph.
PEx:
1) Dix-Hallpike maneuver: have pt sit upright, rotate head 45* to one side then lie the pt down quickly with head hanging off the table. Observe the eyes for 45s, looking for nystagmus.
If you see rotational nystagmus, this is +ve for BPPV. Geotropic = fast phase toward floor. Reversal = sit back up and nystagmus reverses for brief time.
(If there is up or downbeating nystagmus, indicates CNS dysfunction).
Mgmt:
Self-limited, improves over weeks to months.
Can try the ‘Epley maneuver,’ particle repositioning to try to move otoliths in the canals to alleviate vertigo.
Medications not helpful.
Describe acute vestibulopathy
Caused by viral infection.
Acute onset of spontaneous vertigo w/ n/v that usually resolves after 1-2 days. May have residual motion induced vertigo that lasts 1-2 weeks. Progressively improved motion tolerance after this.
No hearing loss.
PEx: look for spontaneous unidirectional nystagmus (fast to affected ear).
No investigations needed, need to exclude CNS or other vestibular pathology.
Mgmt with anti-emetics, early return to physical activity.
Describe Meniere’s disease
Caused by accumulation of endolymph with inadequate reabsorption.
Presents with acute attacks of vertigo, otologic symptoms (tinnitus, aural fullness, hearing loss). Attacks last for minutes to hours.
Audiogram will show hearing loss during episodes with recovery in between. Hearing loss becomes permanent and progressive between episodes. Lower frequencies affected first.
Mgmt:
1) lifestyle modification: low salt, no caffeine/alcohol.
2) Meds: systemic (diuretics, vestibular sedative- betahistine), intra-tympanic (steroids, gentamicin ablation).
3) Surgical: ventilation tube, endolymphatic sac surgery, vestibular neurectomy.
What are the 4 paranasal sinuses, what is their function?
Frontal, ethmoid, maxillary and sphenoid sinuses. Only ethmoid and maxillary sinuses present at birth (the rest develop by age 20 yrs).
Functions:
1) Clean, humidify, moisturize and warm air entering nose.
2) Small, mucous production, immunoprotection, voice resonation.
What is the ostiomeatal complex?
Common drainage pathway for anterior ethmoid, maxillary and frontal sinuses. Area for adequate sinus ventilation.
What is sinusitis, describe the pathophys
What: sinus inflammation that often follows a viral URTI or allergic reactions.
Congestion of sinus ostia may predispose to acute sinusitis.
Closed ostium causes mucosal congestion that blocks airflow and drainage. Results in stagnant secretions -> tissue inflammation -> bacterial infection -> further mucus.
Most common pathogens: strep pneumo, haemophilus influenza, M catarrhalis.
How to diagnose acute sinusitis
URTI that doesn’t resolve in 7 days with worsening symptoms.
Only 2% of viral URTIs will cause acute sinusitis, once >7d, greater likelihood the infection is bacterial.
Symptoms are non-specific and similar to viral URTI’s however viral usually resolves within 5 days.
Diagnosis: 7d w/o symptom improvement or worsening PLUS PODS symptoms:
1) Pain/Pressure/fullness.
2) nasal Obstruction.
3) Discharge: nasal purulence, discolored postnasal d/c.
4) Smell disrupted (anosmia, hyposmia).
Must have obstruction or purulence AND at least 1 other symptom.
On PEx: erythematous, edematous nasal mucosa, purulent d/c, tender sinus. Can percuss face to look for tenderness, fullness.
Investigations for acute sinusitis
imaging is NOT needed (only done if dx is unclear). If XR is done, can look for air-fluid level (only seen if ACUTE sinusitis, not present in chronic).
Anterior rhinoscopy: use nasal speculum _ headlight. Can look for septal deviation and obstruction. Look for polyps or purulence at middle meatus.