HEADACHES CAUSES , TYPES AND TREATMENT
TENSION HEADACHE
HEADACHES
Headaches is an almost universal experience ,and one of the most common symptoms in general and neurological practice .It varies from an infrequent and trivial nulsance to a symptoms of serious disease.
First step - distinguish serious from benign etiologies.Intensity of head pain rarely has diagnostic value :most patients who present to emergency ward with worst headache of their lives have migraine .Headache location can suggest involvement of local structures ( temporal pain in giant cell arteritis ,facial pain in sinusitus ).Rutured aneurysm ( instant onset ) ,cluster headache ( peak over 3-5 minutes ) ,and migraine ( onset over minutes to hours ) differ in times to peak intensity .Provocation by enviormental factors suggests a benign cause.
EVALUATION
Complete neurologic exam is essential first step.If exam is abnormal or if serious underlying cause is suspected for any reason ,an imaging study ( CT or MRI ) is indicated .Lumbar puncture is required when meninges ( stiff neck ,fever ) is a possibility.
MECHANISM
Pain receptors are located at the base of the brain in arteries and veins and throughout the meninges ,extracranial vessels ,muscles of the scalp ,neck and face ,paranasal sinuses ,eyes and teeth .Curiously ,brain itself is almost devoid of pain receptors.
Head pain is mediated by mechanical receptors ( e.g stretching of meninges ) and chemical receptors ( e.g 5-hydoxytryptamine and histamine stimulation ).
Nerve impuses travel centrally via the fifth and ninth cranial nerves and via upper cervical sensory roots.The majority of headaches are benign ,but the diagnostic isssue - and usual source of concern-is that some are caused by serious disease .
The following are some useful clinical pointers.
CHRONIC ( BENIGN ) AND RECURRENT HEADACHES
Almost all recurring headaches lasting hours or days - band like ,generalized head pains ,with a history going back for several years or months - are vaguely ascribed to muscle tension ,and/or migraine .Depression often accompanies them.In localized pain of short duration ,lasting some minutes or hours ,sinusitis ,glaucoma and migranous neuralgia shouls also be considered.Malignant hypertension ,with arterial damage and brain swelling ,occasionally causes headache.Headaches are not caused by high blood pressure alone .
Eyestrain from underlying refractive error is not itself a cause of headache ,though new prescription lenses sometimes provoke pain.
PRESSURE HEADACHES
Intracranial mass lesions displace and stretch the meninges and basal vessels .Pain is provoked when these structures are shifted either by a mass itself or by changes in cerebrospinal fluid ( CSF ) pressure , e.g coughing.Cerebral oedema around brain tumours causes further shift . These pressure headaches typically become worse on lying dpwn.Any headache , however mild ,that is present on waking and made worse by coughing , straining or sneezing may well be due to a mass lesions. Vomiting often accompanies pressure headaches .Such headaches are caused early ,over weeks by posterior focus masses , but over a longer timescale -months or even years - by hemisphere tumours.A rare cause of prostrating headache with lower limb weakness is an intraventricular tumours causing intermittent hydrocephalus .
HEADACHE OF SUBACUTE ONSET
The onset and progression of a headache over days or weeks with or without the features of a pressure headache should always raise the suspicion of an intracranal mass lesions or serious intracranial disease.Encephalitis ,viral meningitis and chronic meningitis should also be considered.
HEADACHES WITH SCALP TENDERNES
Patches of exquisite tenderness overling superficial scalp arteries are caused by giant cell arteritis ,which develops almost exclsively in patients aged over 50 years.
HEADACHE FOLLOWING HEAD INJURY
Subdural haematomas must be considered .However ,the vast majority of post-trauma headaches lasting days, weeks or months are not associated with any serious intracranial pathology.
A SINGLE EPISODE OF SEVERE HEADACHE
This common emergency is caused by one of the following :
Subarachnoid haemorrhage .
Migraine ,or other benign headaches.
Meningitis. ( occasionally ).
Particular attention should be paid to the suddenness of onset ( suggestive of a subarachnoid haemorrhage ) ,neck stiffness and vomiting ( any meningeal irritation ) ,or rash and fever ( bacterial meningitis ).
TENSION HEADACHE
The vast majority of chronic and recurrent headaches are believed to be due to neurovascular irritation and tension within scalp muscles .despite universal occurrence ,precise mechanism of common headache remain obscure .What is certain that most headaches are benign.Tight band sensations ,pressure behind the eyes , throbbing and bursting sensations are common.
There may be obvious precipitating factors such as ,worry ,noise ,concentrated visual efforts or fumes.
Depression is also a frequent underlying cause.Tension headaches are often attributed to cervical spondylosis , refractive erros or high blood pressure ,evidence for these associations is poor .Headaches also follow even minor head injuries.There are no abnormal physical signs other than tenderness and tension in the nuchal and scalp muscles.
MANAGEMENT
This involves :
Firm reassurance.
Avoiding cause .
Analgesics -limited amounts.
Physical treatment - massage ,ice packs , relaxation.
Antidepressants - when indicated.
Drugs for migraine .
Imaging is often needed for reassurance.
