Dizziness

Question 1

Cardiovascular causes of dizziness

Answer 1

• Postural hypotension
• Stroke and TIA
• Carotid sinus syndrome (exaggerated response to carotid sinus baroreceptor stimulation)
• Vertebrobasilar insufficiency
• Aortic stenosis
• Subclavian steal syndrome
• Cardiac arrhythmias.

Question 2

Neurological causes of dizziness

Answer 2

• Following head injury
• Epilepsy
• MS
• Parkinsonism
• Dementia
• Brain tumours, especially brainstem and cerebellar tumours
• Benign intracranial HTN
• Normal pressure hydrocephalus
• Peripheral neuropathy (imbalance or unsteadiness may occur as a result of peripheral neuropathy, spinal posterior column lesions or cerebellar disease).

Question 3

Otological causes of dizziness

Answer 3

• Meniere’s disease
• Benign paroxysmal positional vertigo (BPPV)
• Vestibular neuritis and labyrinthitis
• Vestibular migraine (generally presents with attacks of spontaneous or positional vertigo lasting seconds to days, with associated migraine symptoms).
• Otosclerosis and Paget’s disease of bone
• Middle ear trauma
• Following surgery- e.g. stapedectomy, cochlear implant
• Tumours, cholesteatoma

Question 4

Metabolic causes of dizziness

Answer 4

• Hypoglycaemia
• Adrenal insufficiency
• Hypothyroidism

Question 5

Haematological causes of dizziness

Answer 5

• Anaemia

* Hyper viscosity

Question 6

Psychogenic causes of dizziness

Answer 6

• GAD
• Agoraphobia
• Panic attacks
• Hyperventilation

Question 7

Miscellaneous of dizziness

Answer 7

• Viral illness.
• Migraine headaches
• Other infections - e.g., acute bacterial infections, Lyme disease, HIV infection
• Ocular: visual impairment.
• Cervical - e.g., cervical spondylosis
• Multisensory dizziness syndrome occurs when there are reduced inputs from more than one sensory system - e.g., reduced vision, vestibular dysfunction, peripheral neuropathy, autonomic neuropathy.
• Autoimmune/connective tissue disorders – rheumatoid arthritis, SLE

Question 8

Drug intoxication causes of dizziness

Answer 8

• acute intoxication with alcohol or drugs;
• carbon monoxide poisoning;
• chronic alcohol misuse.

Question 9

Iatrogenic causes of dizziness

Answer 9

• side-effect of medication - e.g., antihypertensives, antidepressants, aminoglycoside antibiotics, anti-arrhythmic. Medication is an extremely common cause of dizziness, particularly in older people.

Question 10

Red flag signs of dizziness

Answer 10

Red flag signs associated with acute dizziness that indicate a possible central neurological cause (such as posterior circulation stroke) include:
• Abnormal neurological symptoms or signs.
• New headache.
• A normal vestibulo-ocular reflex as assessed by the head impulse test (which would imply that the vertigo does not originate in the peripheral vestibular system).

Question 11

Common causes of true vertigo

Answer 11

Labyrinthitis or vestibular neuronitis
BPPV
Vestibular migraine
Ménière’s disease.

Question 12

Classification of dizziness

Answer 12

Vertigo
Presyncope
Disequilibrium
Nonspecific dizziness

Question 13

Clinical features of vertigo

Answer 13

• Vertigo is defined as an abnormal sensation of movement, either of the surroundings or the person.
• Descriptions of vertigo include spinning, tilting, and moving sideways.

Question 14

Causes of vertigo

Answer 14

Most cases seen in primary care are due to peripheral vestibular disorders such as BPPV, acute vestibular neuronitis and Meniere’s disease, but causes also include central nervous system disorders such as vascular incidents or multiple sclerosis.

Question 15

Clinical features of presyncope

Answer 15

• A feeling of light-headedness, muscular weakness and feeling faint. Features may suggest a specific diagnosis.

Question 16

Clinical features of disequilibrium

Answer 16

A sensation of unsteadiness, not localised to the head, that occurs when walking and is relieved with rest.
The most common cause of disequilibrium is ‘multiple sensory deficits’ in elderly patients, who may have deficits with all three balance-preserving senses, ie vestibular, visual and proprioceptive.

Question 17

What are the usual causes of dizziness which is episodic and triggered?

Answer 17

Postural hypotension

BPPV

Question 18

What are the usual causes of dizziness which is episodic and not triggered?

Answer 18

Meniere’s disease
Vestibular migraine
Anxiety attacks

Question 19

What are the causes of dizziness which is persistent and not triggered?

Answer 19

Acute vestibular syndrome (AVS)
The most common cause is vestibular neuritis (dizziness only) or labyrinthitis (dizziness plus hearing loss or tinnitus).

The most frequent central cause is posterior circulation ischaemic stroke, generally in the cerebellum or brainstem.

Question 20

What is AVS?

Answer 20

This is defined as the acute onset of persistent dizziness associated with nausea or vomiting, gait instability, nystagmus, and head-motion intolerance lasting days to weeks.

Question 21

Actions that may provoke dizziness?

Answer 21

• Change in posture (suggests postural hypotension).
• Movement of the head or neck (suggests vertigo from any cause, cervical spondylosis or vertebral artery syndrome).
• Feeling anxious (may indicate hyperventilation).

Question 22

Associated symptoms of dizziness

Answer 22

• Syncope.
• Features suggestive of epilepsy, which need to be considered.
• Falls: consider referring to a falls assessment service.
• Tinnitus or hearing impairment: suggests a vestibular cause.
• Olfactory hallucinations and amnesia, which may suggest a temporal lobe lesion.

Question 23

What should you consider in a patient presenting with dizziness?

Answer 23

Consider medication.

Determine the level of anxiety. It may be present without being the only cause, particularly in older people.

Consider a possible cardiovascular cause; ask about smoking and any other risk factor for cardiovascular disease.

Review past medical history.

Question 24

What are the examinations done to assess dizziness?

Answer 24

Cardiovascular:
• Blood pressure: sitting position, and also supine and standing, to assess any significant postural drop suggesting postural hypotension.
• Aortic murmur (may suggest aortic stenosis and therefore prompt cardiology referral), carotid bruit.

Eyes:
• Visual impairment
• Nystagmus

Ears- looking for infection, herpetic lesions, signs of cholesteatoma

Dix-Hallpike test- BPPV

Neurological:
• Features of cerebrovascular disease, peripheral neuropathy or Parkinsonism.
• Examine gait and ask the patient to do heel to toe walking - if these are abnormal, test reflexes and tone in the lower extremities, and test plantar responses. If gait is unsteady, check for peripheral neuropathy.
• Perform a Romberg’s test. (Ask the person to shut their eyes whilst standing - be ready to support if need be.) A positive test suggests a problem with proprioception or vestibular function. It does not help to distinguish between central and peripheral causes.
• Test co-ordination by asking the patient to put the opposite heel on the knee and to run the foot down and up the shin (assuming the patient is physically able to do this).
• A three-component bedside oculomotor examination - HINTS (horizontal head impulse test, nystagmus and test of skew) - has been shown to identify stroke with high sensitivity and specificity in patients with AVS and rules out stroke more effectively than early diffusion-weighted MRI. It differentiates between a central cause such as stroke, and a peripheral cause of AVS.

Question 25

What investigations do you perform to assess dizziness?

Answer 25

The most useful diagnostic approach in distinguishing different types of dizziness is a thorough history and physical examination and additional tests are rarely necessary

Urinalysis: to exclude urinary tract infection.

FBC: anaemia; mean cell volume (MCV) can be elevated with alcohol abuse.

Renal function, blood glucose, electrolytes, LFTs.

ECG and ambulatory 24-hour ECG for possible arrhythmia.

Further investigations may include electroencephalography (EEG), CT or MRI brain scan, pure tone audiometry, vestibular function tests (e.g., electronystagmography), further cardiology investigations (e.g., echocardiogram) or other investigations suggested by the presentation of each individual patient.