Vertigo

Vertigo is a subjective sensation of movement, usually rotatory but sometimes linear. It is often accompanied by pallor, sweating and vomiting. The objective sign of vertigo is nystagmus. Bodily balance is maintained by the input to the brain from the inner ear, the eyes and the proprioceptive organs, especially of the neck; dysfunction of any of these systems may lead to imbalance. The diagnosis of the cause of vertigo or imbalance depends mostly on history, much on examination and little on investigation. The particular questions to be asked relate to three areas. 1 Timing: episodic, persistent. 2 Aural symptoms: deafness, fluctuating or progressive; tinnitus; earache; discharge. 3 Neurological symptoms: loss of consciousness; weakness; numbness; dysarthria; diplopia; fitting. Table 15.1 gives a guide to diagnosis following history-taking and will direct any specific examination and investigation. Menière’s disease Menière’s disease is a condition of unknown aetiology in which there is distension of the membranous labyrinth by accumulation of endolymph. It can occur at any age, but its onset is most common between 40 and 60 years. It usually starts in one ear only, but in about 25% of cases the second ear becomes affected.The clinical features are as follows. 1 Vertigo is intermittent but may be profound, and usually causes vomiting. The vertigo rarely lasts for more than a few hours, and is of a rotational nature. 2 A feeling of fullness in the ear may precede an attack by hours or even days. 3 Deafness is sensorineural and is more severe before and during an attack. It is associated with distortion and loudness intolerance (recruitment). Despite fluctuations, the deafness is usually steadily progressive and may become severe. 4 Tinnitus is constant but more severe before an attack. It may precede all GUIDE TO DIAGNOSIS OF VERTIGO Episodic with aural symptoms Menière’s disease Migraine Episodic without aural symptoms Benign paroxysmal positional vertigo Migraine Transient ischaemic attacks Epilepsy Cardiac arrhythmia Postural hypotension Cervical spondylosis Constant with aural symptoms Chronic otitis media with labyrinthine fistula Ototoxicity Acoustic neuroma Constant without aural symptoms Multiple sclerosis Posterior fossa tumour Cardiovascular disease Degenerative disorder of the vestibular labyrinth Hyperventilation Alcoholism Solitary acute attack with aural symptoms Head injury Labyrinthine fistula Viral infection, e.g.mumps,herpes zoster Vascular occlusion Round-window membrane rupture Solitary acute attack without aural symptoms Vasovagal faint Vestibular neuronitis Trauma Table15.1 Guide to diagnosis of vertigo. other symptoms by many months, and its cause only becomes apparent later. TREATMENT General and medical measures In an acute attack, when vomiting is likely to occur, oral medication is of limited value, but cinnarizine, 15–30 mg 6-hourly, or prochlorperazine, 5–10 mg 6-hourly, are useful preparations. Alternatively, prochlorperazine can be given as a suppository or sublabially, or chlorpromazine (25 mg) may be given as an intramuscular injection. Between attacks, various methods of treatment are useful. 1 Fluid and salt restriction. 2 Avoidance of smoking and excessive alcohol or coffee. 3 Regular therapy with betahistine hydrochloride, 8–16 mg t.d.s. 4 If the attacks are frequent, regular medication with labyrinthine sedatives, such as cinnarizine, 15–30 mg t.d.s., or prochlorperazine, 5–10mg t.d.s., are of value. Regular low-dose diuretic therapy may also be of benefit. Surgical treatment 1 Labyrinthectomy is effective in relieving vertigo, but should only be performed in the unilateral case and when the hearing is already severely impaired. 2 Drainage of the endolymphatic sac by the transmastoid route. 3 Division of the vestibular nerve either by the middle fossa or by the retrolabyrinthine route; this operation preserves the hearing but is a more hazardous procedure. 4 Intra-tympanic gentamycin is helpful in reducing vestibular activity but with a 10% risk of worsening the hearing loss. Menière’s disease is fortunately uncommon, but may be incapacitating. The patient requires constant reassurance and sympathetic support. Vestibular neuronitis Although occasionally epidemic, vestibular neuronitis is probably of viral origin and causes vestibular failure.The vertigo is usually of explosive onset, but there is neither tinnitus nor deafness. Steady resolution takes place over a period of 6–12 weeks but the acute phase usually clears in 2 weeks. Benign paroxysmal positional vertigo Benign paroxysmal positional vertigo is due to a degenerative condition of the utricular neuroepithelium and may occur spontaneously or following head injury. It is also seen in CSOM. Attacks of vertigo are precipitated by turning the head so that the affected ear is undermost; the vertigo occurs following a latent period of several seconds and is of brief duration. Nystagmus will be observed but repeated testing results in abolition of the vertigo. Steady resolution is to be expected over a period of weeks or months. It may be recurrent. It can often be relieved completely by the Epley manoeuvre of particle repositioning by sequential movement of the head to move the otolith particles away from the macula. Vertebrobasilar insufficiency Vertebrobasilar insufficiency may cause momentary attacks of vertigo precipitated by neck extension, e.g. hanging washing on a line.The diagnosis is more certain if other evidence of brain stem ischaemia, such as dysarthria or diplopia, is also present. Severe ischaemia may cause drop attacks without loss of consciousness. Ototoxic drugs Ototoxic drugs, such as gentamycin and other aminoglycoside antibiotics, can cause disabling ataxia by destruction of labyrinthine function. Such ataxia may be permanent and the risk is reduced by careful monitoring of serum levels of the drug, especially in patients with renal impairment.There is not usually any rotational vertigo. Trauma to the labyrinth Trauma to the labyrinth causing vertigo may complicate head injury, with or without temporal bone fracture. Post-operative vertigo Post-operative vertigo may occur after ear surgery, especially stapedectomy, and will usually settle in a few days. Suppurative labyrinthitis Suppurative labyrinthitis causes severe vertigo (see complications of middle-ear disease). It also results in a total loss of hearing. Syphilitic labyrinthitis Syphilitic labyrinthitis from acquired or congenital syphilis is very rare but may cause vertigo and/or progressive deafness. Do not forget the spirochaete. Acoustic neuroma Acoustic neuroma (vestibular schwannoma) is a slow-growing benign tumour of the vestibular nerve that causes hearing loss and slow loss of vestibular function. Imbalance rather than vertigo results. Geniculate herpes zoster Geniculate herpes zoster (Ramsay Hunt syndrome) usually causes vertigo, along with facial palsy and severe pain in the ear. Perilymph fistula As a result of spontaneous rupture of the round-window membrane or trauma to the stapes footplate, perilymph fistula causes marked vertigo with tinnitus and deafness. There is usually a history of straining, lifting or subaqua diving in the spontaneous cases, and treatment is by bed-rest initially, followed by surgical repair if symptoms persist.