Migraine derived from the Greek words hemi means half and kranion means skull. It is a characterised by periodic headaches usually unilateral and often associated with vomiting and visual disturbance. The intensity of pain ranges from mild to severe and is more common in females than males.
Typical migraine headache is unilateral (one sided), throbbing in nature and lasts from few hours to several days.
Aetiology of Migraine :
The exact cause of migraine is unknown. Migraine headache is believed to be due to a dist-urbance in the carotid or vertebro-basilar vascular tree. An initial phase of vasoconst-riction causes symptoms of local cortical or brain stem ischemia followed by vasod-ilatation. These changes affect both intra and extra cranial arteries. Dilatation of the extra cranial vessels causes pain by stretching the pain nerve-endings in the arterial wall. Pain may be prolonged by secondary muscular contraction.
Heredity plays an important role. Migraine and essential hypertension are closely linked in the family. Patient with migraine often has an obsessional personality. Migr-aine is a prototype of psychosomatic disease and it is common for 'typical migraine attacks' to be associated with tension headache.
Clinical Features of Migraine :
• Typical migraine headache is unilateral (one sided) throbbing in nature and lasts for few hours to several days.
• Roughly 30% of people having migraine headache perceive of attack, an aura (a transient visual, sensory, language or motor disturbance signating the migr-aine will soon occur).
• Symptoms of migraine headache are nausea, vomiting, increased sensitivity to light (Photophobia) and increased sensitivity to sound (Phonophobia).
• The condition usually starts after puberty and continues until late middle life.
• Headache occurs in paroxysms which often related to emotional stress, partic-ularly during the period of relaxation when the stress is over.
• Attacks occur at intervals which vary from a few days to several months.
• The first symptom of an attack is due to vasospasm. This is most commonly a sensation of white or coloured lights, scintillating spots, wavy lines, or defects in the visual fields.
• Paraesthesiae or weakness of one half of the body may be experienced or there may be numbness of both hands and around the mouth. These symptoms may last up to half an hour, and are followed by headache.
• The pain is usually severe and throbbing in character and is associated with vomiting, photophobia, pallor, sweating and prostration which may cause severe loss of muscle tone and necessitate the patient taking her/ his bed in a darkened room.
• The attack may last from a few hours to several days and leaves the patient weak and exhausted.
• In rare cases the cerebral changes may last for several days, particularly if the motor area is involved (hemiplegics migraine).
• Permanent cortical damage may result, usually leaving a visual scotoma of cortical type.
Types of Migraine :
According to International Classification of Headache Disorders there are 7 types of sub classes of migraine. They are as follows:
• Migraine without aura
• Migraine with aura
• Childhood periodic syndromes that are commonly precursors of migraine
• Retinal migraine
• Complications of migraine
• Probable migraine
• Chronic migraine
Objective signs of Migraine :
A temporary Horner's Syndrome which is characterised by Ptosis (drooping eye lid)
and Miosis (smaller pupil) may occur during migraine attack and disappear afterwards.
Things that Activate (Triggers) Migraine :
Common triggers of migraine stress, fatigue and hunger (which causes tension heada-che). Migraines are more likely to occur in pregnancy, oral pills (contraceptives) use, menarche, perimenopause and menopause.
Migraine attacks may be activated by following triggers :
• Physical or emotional stress
• Use of alcohol
• Bright lights
• Due to allergic reactions
• Perfumes or certain specific odours
• Change in hormone levels
• Vigorous exercises
• Changes in pattern of sleep
• Excessive loud noises
• Smoking or even exposure to smoke
• There may be food related triggers like any processed, marinated, fermented or pickled foods. Baked items, dairy products, chocolate, chicken livers, smoked fish, certain brains etc.
• Certain fruits like banana and citrus fruits may precipitate migraine.
• True migraine headaches are not due to or as a result of a brain tumour or other serious medical problems.
How a Migraine Headache is Diagnosed :
• There is no specific sign of migraine headache.
• Only your doctor can diagnose the migraine by asking relevant questions about symptoms and family history of migraine.
• A thorough clinical examination is done by your doctor to exclude muscle tension, sinus problems or any serious brain/meninges disease.
• There is no specific test which confirms that your headache is really a migraine.
• MRI or CT scan is advised in patients having unusual symptoms migraine like weakness, memory problems or loss of attention.
• Lumber Puncture for cerebro spinal fluid exa-mination may be required to exclude meningeal and brain diseases.
• EEG may be needed to exclude seizures.
Treatment of migraine:
The patient should rest in a quiet dark room. There are 3 main aims of treatment of migraine-
1. Avoid migraine triggers
2. Acute symptomatic relief
Frequent use of drugs leads to drug overuse headache, in which the headaches become more severe and more frequent. It often occurs with triptans, ergotamines and narcotic analgesics.
Non Steroidal Anti Inflammatory Drugs (NSAIDs) like:
Ibuprofen : relief pain in 50% migraine patients.
Naproxen : relief pain in about 1/3 cases
Aspirin : 1000mg can relief moderate to severe migraine pain.
Paracetamol / acetaminophen either alone or with metaclopramide, are effective in migraine.
Simple analgesics combined with caffeine may be effective in migraine.
Triptans such as sumatripan are effective for both pain and nausea. It is available in oral, injection, nasal spray and dispersible tablets with mild side effects like flushing and rarely myocardial ischemia. They cause drug induced headaches if triptans is used more than 10 days in a month.
Ergotamines are older drugs still used for migraines. Di-hydro-ergotamine is also available as nasal spray and injection. Too frequent use of ergotamine may cause peripheral vasoconstriction leading to gangrene of fingers or toes. It is best avoided in patients with hypertension and is contraindicated during pregnancy.
A single dose of i/v dexamethasone when added to routine treatment of a migraine attack reduces the headache recurrence.
Anti emetic orally may relief symptoms of nausea and vomiting which increase the efficiency of analgesics.
General management of patient is very important. An attempt should be made to avoid obvious precipitating factors and by means of simple psychotherapy the patient should be encouraged to adopt less exacting standards.
Complications of Migraine :
Migraine headache is a risk factor for myocardial ischemia (stoke) in both sexes. Migraine headache can be a chronic problem and may interfere with your day to day life.
Prognosis of Migraine :
The response of treatment for migraine differs from person to person. Some people have mild headache that require little to no treatment, while others require the use of several medications or even hospitalization.