There are more than 300 conditions that can present with headache. But with experience and expertise the headache specialist will be able to sift through this long list and cone down on the most likely cause of your headache. Some conditions are seen more commonly than others for e.g. migraine is the commonest cause of headache that is seen in practice and not sinus-related or eye-related headache as patients generally think. The International Headache Society has simplified the approach to diagnosis by dividing all headaches into either Primary or Secondary headaches.
Primary headaches are those headaches where there is no abnormality seen or examination or investigation. The diagnosis is made by pattern-recognition. Migraine, cluster headache and tension-type headache are some of the common primary headaches.Secondary headaches are those headaches where there is an abnormality on examination or investigation. Headaches due to braintumors, meningitis or brain haemorrhage are some examples of secondary headaches. The pain can be just as severe whether the underlying cause is primary or secondary. Your specialist is trained and experienced to sift through the different causes, examine thoroughly, investigate appropriately and come to a conclusion as to the type of headache you suffer from and then choose the right type of treatment accordingly.