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Chapter 7: Clinical 289

Table 7.2 Peripheral lesions causing vertigo
Causes Characteristics of vertigo Hearing loss and tinnitus
Acute vestibular neuronitis Acute onset, lasting 2–5 days None
Benign paroxysmal positional vertigo (BPPV) Postural, lasting <1 min None
M´eni`ere’s disease 10 min to 10 h Yes
Barotrauma & perilymphatic fistula Inducible by pressure changes Yes
Drugs such as aminoglycosides Some cases

or head trauma. Positional testing with the Hallpike appears after a few seconds (latency), lasts less than
manoeuvre is diagnostic. 30 seconds (transience), and disappears with repeated
The Hallpike manoeuvre (see Fig. 7.1): The patient testing (fatigable).

is swung rapidly from a sitting position to lying with Anyatypical features suggest a central lesion.
the neck extended and turned to one side (so that M´ eni` ere’s disease is a triad of episodic vertigo lasting
the head hangs over the end of the bed). The pa- a10 minutes to 10 hours, tinnitus and hearing loss. It
tient’seyesarecloselyobservedfornystagmusforupto responds poorly to vestibular sedatives.
30 seconds, then sat upright and nystagmus looked for
again. This is repeated on the other side. This test can Central lesions
provoke intense nausea, vertigo and even vomiting, Acentral lesion due to disease of the brainstem, cere-
particularly in peripheral lesions. In BPPV nystamus bellum or cortex should be suspected if the history and
examination are atypical for a peripheral lesion. For ex-
ample, risk factors for cerebrovascular disease, previous
history of migraine, demyelination, or the presence of
any other neurology. Deafness and tinnitus do not occur
with central lesions.
Causes include multiple sclerosis, migraine, stroke
particularly cerebellar infarction or haemorrhage, ver-
tebrobasilar ischaemia (posterior circulation TIA), tu-
mour of the cerebellopontine angle, cerebellum, fourth
ventricle or acoustic neuroma.

Altered sensation or weakness in
the limbs

Altered sensation in the limbs is often described as
numbness, pins and needles (‘paraesthesiae’), cold or
hot sensations. Painful or unpleasant sensations may be
felt, such as shooting pains, burning pain, or increased
sensitivity to touch (dysaesthesia). There may be a pre-
cipitating cause, such as after trauma, or exacerbating
features.
The distribution of the sensory symptoms, and any
associated pain (such as radicular pain, back pain or
neck pain) can help to determine the cause.
Muscle weakness (loss of power) may occur in specific
Figure 7.1 The Hallpike maneouvre. muscles or muscle groups.