vertigo.
The two most common causes of severe vertigo are acute labyrinthitis and Mèniére's disease.
Acute Labyrinthitis
This occurs during an acute febrile disease such as influenza. The patient develops a sense of
whirling with a sudden onset. Nausea and vomiting may occur. The patient has to lie flat and the
slightest movement brings on the vertigo. The symptoms gradually subside and disappear in 3 to
6 weeks. There is no accompanying tinnitus or hearing loss.
Meniere's Disease
This is characterized by recurring bouts of sudden vertigo, tinnitus and deafness. In the intervals
between bouts the patient has complete freedom from vertigo, but the tinnitus and deafness
continue.
Eighth Cranial Nerve
This can be affected by acute meningitis, trauma and tumours. Damage to the eighth nerve
produces vertigo, nystagmus (involuntary rapid movement of the eyeball) and hearing loss.
Brainstem
This can be affected by infections (encephalitis, meningitis), trauma, thrombosis of the
posteroinferior cerebellar artery and multiple sclerosis.
Damage to the brainstem causes vertigo and nystagmus but no hearing loss.
Transient vertigo may be caused by a vascular spasm.