ENT - vertigo

Question 1

What is vertigo?

Answer 1

a sensation that there is movement between the patient and their environment.

Feeling like they are moving or that the room is moving

Often a horizontal spinning sensation

Question 2

What is the pathophysiology of vertigo?

Answer 2

A mismatch between the sensory inputs of vision, vestibular system and proprioception

Question 3

What makes up the vestibular system? How does it work?

Answer 3

3 semicircular canals filled with endolymph orientated at different angles

Cilia detect small changes in the shifting fluid - these are located in the ampulla

The sensory input of shifting fluid is transmitted to the vestibular nucleus in the brainstem and the cerebellum via the vestibular nerve to inform the brain that the head is moving

Vestibular nucleus sends signals to CN3,4,6 (control eye movements), the thalamus, spinal cord and cerebellum

Cerebellum is responsible for co-ordinating movements throughout the body

Question 4

Central vs peripheral vertigo

Answer 4

Peripheral vertigo - a problem usually with the vestibular system

Central vertigo - a problem with the brainstem or cerebellum

Question 5

Vestibular (peripheral) causes of vertigo - main 4

Answer 5

BPPV

Meniere’s disease

Vestibular neuronitis

Labrynthitis

Question 6

What is BPPV? Pathophysiology?

Answer 6

Calcium carbonate crystals called otoconia that become displaced into the semicircular canals

They may be displaced by a viral infection, head trauma, ageing or without a clear cause.

The crystals disrupt the normal flow through the canals and therefore disrupt the function of the system.

Question 7

How does BPPV present an why?

Answer 7

Positional vertigo - as movement is required to confuse the vestibular system

Improved on staying still

Nystagmus

Question 8

What causes Meniere’s disease?

Answer 8

Excessive buildup of endolymph in the semicircular canals causing increased pressure

This disrupts the sensory signals

Question 9

Presentation of Meniere’s disease

Answer 9

Attacks of vertigo last several hours with episodes of nystagmus and they arent triggered by positions

Symptoms of hearing loss, tinnitus and vertigo
Sensation of fullness in the ear

Question 10

What is acute vestibular neuronitis?

Answer 10

Inflammation of the vestibular nerve

Usually attributed to a viral infection but this may be asymptomatic

Disruption to the nerve causes mismatch of signals causing vertigo

History of acute onset of vertigo that lasts several weeks before gradually resolving

Question 11

Other causes of peripheral vertigo

Answer 11

Trauma to the vestibular nerve

Vestibular nerve tumours - acoustic neuromas

Otosclerosis

Hyperviscosity syndromes

Herpes zoster infection (often with facial nerve weakness and vesicles around the ear - Ramsay Hunt Syndrome)

Question 12

How to differentiate between vestibular neuronitis and labrynthitis?

Answer 12

Labyrinthitis is inflammation of the structure of the inner ear - usually attributed to a viral infection

Labyrinthitis can cause hearing loss which does not occur in vestibular neuronitis

Question 13

Most common central causes of vertigo

Answer 13

Posterior circulation infarction (stroke)

Tumour

Multiple sclerosis

Vestibular migraine

Question 14

What symptoms may suggest a posterior circulation stroke?

Answer 14

Sudden onset

May be associated with other symptoms e.g. ataxia, diplopia, cranial nerve defects or limb symptoms

Question 15

What symptoms may suggest a tumour causing vertigo?

Answer 15

Tumours in the cerebellum or brainstem will have gradual onset with associated symptoms of cerebellar or brainstem dysfunction

Question 16

What symptoms may suggest MS causing vertigo?

Answer 16

Relapsing and remitting symptoms

Other associated features of MS e.g. optic neuritis or transverse myelitis

Question 17

What symptoms may suggest vestibular migraine causing vertigo?

Answer 17

Symptoms lasting minutes to hours

Often associated with visual aura and headache

Attacks may be triggered by - stress, bright lights, certain foods, dehydration, menstruation

Question 18

Examinations that can be done in vertigo assessment

Answer 18

Ear examination

Neurological examination

CV examination (CV causes of dizziness e.g. arrhythmias, valvular disease)

Cerebellar examination

Special tests:

• Romberg’s test
• Dix-Hallpike manoeuvre
• HINTS examination

Question 19

How to perform a cerebellar examination?

Answer 19

DANISH

D- Dysdiadochokinesia
A- Ataxic gait - ask patient to walk heel to toe
N- nystagmus (as in HINTS exam)
I - intention tremor
S - slurred speech
H - heel-shin test

Question 20

What is Romberg’s test?

Answer 20

Screens for problems with proprioception or vestibular function

First patient stands with eyes open and then eyes closed

Observer standing nearby to assist if the patient becomes imbalanced

Question 21

What is the HINTS examination and how do you perform it?

Answer 21

HI - head impulse:

• Check no neck pain
• Ask the patient to sit and look at your nose
• Rapidly jerk head 10-20 degrees in one direction and then slowly return to centre
• Repeat on other side
• Normal/central cause of vertigo - the patient’s eyes stay fixed on the nose
• Peripheral cause of vertigo, the eyes will saccade (rapidly move back and forth) to eventually focus back on the nose

N - nystagmus:

• Ask the patient to look left and right without focusing on any object
• Unilateral/horizontal nystagmus - more likely to be peripheral origin of vertigo
• Bidirectional nystagmus/vertical - more likely central origin

TS - test of skew

• Also called the alternate cover test
• Sit patient upright and ask to focus on your nose
• Cover one of the patient’s eyes
• Quickly move to cover the other eye and observe the uncovered eye for any vertical/diagonal movement
• Repeat the other side
• The eyes should remain fixed on the examiner’s nose
• If there is vertical correction, suggests a central cause of vertigo

Question 22

Management of vertigo

Answer 22

Central vertigo - referral for further investigation e.g. CT/MRI head to establish cause

Peripheral vertigo STM of Sx - Prochlorperazine
- Antihistamines e.g. cyclizine

Specific treatments:

• Betahistine in Menieres to reduce attack
• Epley manoeuvre in BPPV
• Avoidance of triggers, triptans and general migraine prophylaxis in vestibular migraine