ENT - Balance Flashcards
(45 cards)
What are some causes of secondary tinnitus?
- impacted ear wax
- ear infection
- ménière’s disease
- noise exposure
- medications
- acoustic neuroma
- multiple sclerosis
- trauma
- depression
Which medications are associated with tinnitus?
- loop diuretics
- gentamicin
- chemotherapy drugs (e.g. cisplatin)
Systemic conditions associated with tinnitus.
- anaemia
- diabetes
- hyperthyroidism
- hypothyroidism
- hyperlipidaemia
What is objective tinnitus?
When a patient can objectively hear an extra sound within their head. This sound can also be observable on examination by auscultating with a stethoscope around the ear.
Causes of objective tinnitus.
- carotid artery stenosis (pulsatile carotid bruit)
- aortic stenosis (radiating pulsatile murmur)
- arteriovenous malformation
- Eustachian tube dysfunction
Investigations for tinnitus.
Laboratory investigations to exclude underlying causes:
- full blood count (?anaemia)
- HbA1c (?diabetes)
- TSH (?thyroid disorder)
- lipids (?hyperlipidaemia)
Specialist investigations may be audiometry and imaging (CT / MRI).
Tinnitus red flags.
- unilateral
- pulsatile
- hyperacusis
- unilateral hearing loss
- sudden onset hearing loss
- vertigo / dizziness
- headaches / visual symptoms
- neurological symptoms
- suicidal ideation
May indicate a serious underlying pathology and the need for specialist assessment.
Management of tinnitus.
Tinnitus tends to improve or resolve over time without interventions.
Any identifiable causes should be managed.
Measures to help improve and manage tinnitus:
- hearing aids
- sound therapy
- CBT
What is vertigo?
A descriptive term for a sensation that there is movement between the patient and their environment.
Sensory inputs responsible for maintaining balance and posture.
- vision
- proprioception (cerebellum)
- signals from the vestibular system
Vertigo can be caused by either a:
1)
2)
1) peripheral problem (affecting vestibular system)
2) central problem (affecting the brainstem or cerebellum)
Give some peripheral causes of vertigo.
- benign paroxysmal positional vertigo (BPPV)
- Ménière’s disease
- vestibular neuronitis
- labyrinthitis
Give some central causes of vertigo.
- posterior circulation stroke
- tumour
- multiple sclerosis
- vestibular migraine
Peripheral vertigo history
a) onset
b) duration
c) hearing loss or tinnitus
d) coordination
e) nausea
a) acute
b) short (seconds or minutes)
c) often present
d) intact
e) severe
Central vertigo history
a) onset
b) duration
c) hearing loss or tinnitus
d) coordination
e) nausea
a) gradual (except POCS)
b) persistant
c) rarely
d) impaired
e) mild
What should be examined when assessing a patient presenting with vertigo?
- Otoscopy - look for signs of infection or other pathology.
- Neurological examination - assess for central causes of vertigo.
- Cardiovascular examination - assess for arrhythmias or valve disease)
- Special tests
Which clinical signs indicate central vertigo.
DANISH - cerebellar components.
Dysdiadokinesia
Ataxic gait (heel-to-toe)
Nystagmus
Intention tremor
Speech (slurred)
Heel-Shin test
Which examination can be performed to distinguish between a central and peripheral vertigo?
HINTS examination
Head Impulse
Nystagmus
Test of Skew
What is the Head Impulse test?
The head impulse test involves the patient sitting upright and fixing their gaze on the examiner’s nose. The examiner holds the patient’s head and rapidly jerks it 10-20 degrees in one direction while the patient continues looking at the examiner’s nose. The head is moved slowly back to the centre before repeating in the opposite direction. Ensure they have no neck pain or pathology before performing the test.
A patient with a normally functioning vestibular system will keep their eyes fixed on the examiner’s nose.
In a patient with an abnormally functioning vestibular system (e.g., vestibular neuronitis or labyrinthitis), the eyes will saccade (rapidly move back and forth) as they eventually fix back on the examiner.
The head impulse test helps diagnose a peripheral cause of vertigo but will be normal if the patient has no current symptoms or a central cause of vertigo.
What are the causes of nystagmus?
a) unilateral horizontal nystagmus
b) bilateral vertical nystagmus
a) peripheral vertigo
b) central vertigo
What is the Test of Skew?
Involves the patient sitting upright and fixing their gaze on the examiner’s nose. The examiner covers one eye at a time, alternating between covering either eye. The eyes should remain fixed on the examiner’s nose with no deviation.
If there is a vertical correction when an eye is uncovered (the eye has drifted up or down and needs to move vertically to fix on the nose when uncovered), this indicates a central cause of vertigo.
Pathophysiology of benign paroxysmal positional vertigo (BPPV).
Otoconia (calcium crystals) become displaced into the semicircular canals.
This disrupts the normal flow of endolymph through the canals, confusing the vestibular system.
Head movement creates the flow of endolymph in the canals, triggers episodes of vertigo.
Which structure in the semicircular canal is most commonly affected in BPPV?
Posterior semicircular canal.
Causes of otoconia displacement (BPPV).
- viral infection
- head trauma
- ageing
- idiopathic
