Central or peripheral features may be further elicited on careful neurological examination.


Nystagmus is an important clinical sign which may indicate the underlying cause of vertigo. It consists of an initial smooth movement in one direction followed by a rapid movement (saccade) to the opposite direction. Nystagmus is described according to the direction of its fast component. The fast component is also interchangeably used with the term ‘beat’, e.g. when the fast component is downwards = downbeat nystagmus. Nystagmus can be physiological (e.g. looking out of the window of a moving train) or pathological. It is normal to see a few self-limiting beats of nystagmus on extreme lateral gaze. When pathological, it is very useful in deciding whether vertigo has a central or peripheral cause.

Central causes of nystagmus may produce horizontal, vertical or rotational nystagmus. Importantly, the nystagmus does not suppress with visual fixation, is typically bi-directional and may change direction with gaze.

Peripheral causes of nystagmus produce typically unidirectional horizontal or horizontal-rotational nystagmus and is usually suppressed with visual fixation.

In the case of BPPV, it can be precipitated by head movement, e.g. Dix-Hallpike manoeuvre, but fatigues (habituates) with time with the head in the same position.

Learning Bite

Central nystagmus is typically bi-directional. Peripheral nystagmus is typically unidirectional.

Patients with acute vertigo

Patients with acute vertigo should undergo a thorough neurological examination including assessment of gait and cerebellar function.

The presence of other neurological signs suggests a central cause, and patients with vertigo due to stroke nearly always have other evidence of brainstem ischaemia, for example diplopia, dysarthria, numbness or weakness. Conversely, true isolated vertigo or dizziness very rarely indicates a stroke, and is found in less than 1% of such patients. However, it can occur in an isolated cerebellar lesion or infarct.

Many patients with vertigo will feel unsteady on standing. However, those with peripheral vertigo can usually stand unaided, whilst those with a central cause require assistance.

Otoscopy should be performed to exclude outer or middle ear pathology such as vesicles in herpes zoster or otitis media. If there is hearing loss, bedside auditory tests, i.e. Rinne and Webber tuning fork tests, should be performed to distinguish between conductive and sensorineural hearing loss. The presence of either support a diagnosis of peripheral vertigo. However, remember that some common peripheral causes of vertigo, such as vestibular neuritis or BPPV, are not typically associated with auditory symptoms or signs.

Learning Bite

Patients with central causes of nystagmus usually have other signs of cerebellar/brainstem dysfunction.

Patients with suspected BPPV

In patients with suspected BPPV, confirmatory bedside tests such as the Dix-Hallpike manoeuvre can be performed to test for posterior canalithiasis (the commonest cause for BPPV).

The sensitivity of this test ranges from 55% to 88%, but a positive test justifies the use of canalith repositioning manoeuvres, such as the Epley manoeuvre (see section 15), which may be curative.