HEADACHE

- Most patients with headaches have tension-type or migraine headache - Most patients with headaches have tension-type or migraine headache.The diagnosis in these cases is made entirely from the history because there are usually no physical signs. -However,headache can also be secondary to other disorders affecting the head and neck,and it is sometimes the predominant symptom of serious intracranial disease such as tumour, CNS infection or subarachnoid hemorrhage.

- Pain in the head and neck may be referred from the ears,eyes,nasal passages,teeth,sinuses,facial bones and cervical spine. - It is conveyed predominantly by the trigeminal nerve( 5th cranial nerve),and also by the 7th,9th and 10th cranial nerves,and the upper 3 cervical roots.

-Structures of the anterior and middle cranial fossa generally refer pain to the anterior two-thirds of the head via the branches of the trigeminal nerve ; -Structures of the posterior fossa refer pain to the back of the head via the upper cervical roots( Fig).

The approach to assessing a patient with headache should be based on the temporal pattern of symptoms,especially the mode of onset and subsequent course. This may be: * Recurrent and episodic with acute or subcute onset. * Chronic and daily with fluctuations in severity over months or years. * Subacute onset and progressive over days to weeks. * Acute onset and progressive over hours.

1.Recurrent episodic headache - Recurrent episodic headache is usually benign and is very rarely due to sinister pathology. - Common causes and their clinical features are listed in the figure.

2. Chronic daily headache Chronic daily headache is most often diffuse tension-type headache and is rarely due to serious intracranial disease (Fig).

3.Subacute-onset and progressive headache -The category of subacute-onset headache includes most of the serious causes of headache. - Worrying features include a progression of the headache,persisting focal symptoms or signs,deterioration of conscious level,seizures and associated fever(Fig).

4.Acute–onset headache -Instantaneous onset should always raise the suspicion of intracranial hemorrhage or arterial dissection. - There are also benign causes such as recurrent coital or exertional headache and thunderclap-type migraine( Fig).

HISTORY A good history is essential to the diagnosis of the type of headache.Determine: - Mode of onset:acute,subacute,chronic,or recurrent and episodic. - Subsequent course:episodic,progressive or chronic. - Site: unilateral or bilateral;frontal,temporal or occipital;radiation to neck,arm or shoulder.

stabbing or dull/pressure-like. - Frequency and duration. - Character of pain: constant,throbbing, stabbing or dull/pressure-like. - Frequency and duration. -Accompanying features:additional neurological symptoms,neck stiff ,autonomic symptoms. -Exacerbating factors:movement,light,noise,smell (e.g.migraine),coughing,sneezing,bending (e.g. raised intracranial pressure).

Precipitating factors: alcohol( cluster headache and migraine),menstruation (migraine),stress (most headaches are worse with stress),postural change( high or low intracranial pressure headache), head injury (subarachnoid hemorrhage or post-traumatic headache)

- Particular time: mornings(migraine,raised intracranial pressure),awoken at night ( cluster headache). - Past history of headache. - Family history: migraine,intracranial hemorrhage. - General health: systemic ill health,existing medical conditions. - Drug history:analgesic abuse,recreational drugs.

EXAMINATION When examining a patient with headache, look for: *Level of consciousness. * Focal neurological signs. * Signs of local disease of the ears,eyes,or sinuses;restriction of neck movements and pain;temporomandibular joint dysfunction;thickening of the superficial temporal arteries. * Signs of systemic disease * Abnormal blood pressure. The clinical examination is often entirely normal.

SUMMARY a) Headache might be: - Primary,e.g. migraine,tension-type headache,cluster headache. -Secondary e.g.subarachnoid hemorrhage, meningitis,raised intracranial pressure. b)The temporal pattern of symptoms should be established (i.e. the mode of onset and subsequent course- recurrent and episodic,chronic,subacute or acute).A list of differential diagnoses based on the temporal pattern of symptoms should be drawn up. c) The examination may demonstrate focal neurological signs( e.g. papilloedema,which suggests a secondary headache).

Features that should alert the clinician to the presence of a secondary headache and prompt further investigation are: - Recent onset/short history( particularly in middle age with no previous history of headache). - Acute onset or progressive course. - Recent change in established pattern or character of headache. - Increasing severity with resistance to appropriate and adequately tried treatment. - Associated features-neurological signs,seizures, personality change,fever,systemic illness.