Headache

Meningitis

Meningitis is characterized by progressive headache developing over hours or days (Fig. 1b). There is an associated fever and neck stiffness, and there may be a rash and impaired consciousness. As early treatment favours a good prognosis, a high threshold of suspicion is needed (p. 98).

Temporal arteritis (or giant cell arteritis)

This is a vasculitis that affects middle-sized arteries. It is dangerous because the arteritis can affect retinal vessels and cause blindness. It occurs in patients aged over 50 years and the incidence increases with age (1 in 100 000 aged over 50 years and 800 in 100 000 over 80 years). Women are affected twice as commonly as men.

The headache is insidious in onset and may be unilateral or more generalized, though it usually produces bitemporal pain (Fig. 1c). The scalp is often tender. A specific symptom is ‘jaw claudication’, the development of pain in the muscles of mastication on chewing. Twenty-five per cent of patients also have generalized joint and muscle aching typical of polymyalgia rheumatica.

The erythrocyte sedimentation rate (ESR) is elevated, usually strikingly (60–100), as are other serological inflammatory markers such as plasma viscosity and C-reactive protein. The diagnosis is confirmed by a biopsy of a temporal artery; however, this may be negative as the arteritic lesions are patchy. If the diagnosis is suspected, treatment with steroids should be started immediately, to which there is usually a brisk response. Treatment is monitored using the ESR and can usually be stopped within 2 years.

Raised intracranial pressure

The ‘classical’ headaches of raised intracranial pressure (ICP; p. 48) are generalized and made worse or brought on by manoeuvres that increase ICP such as coughing, bending or lying down (Fig. 1d); for this reason they are worse on waking in the morning and tend to clear within a short time of getting up. They may be associated with vomiting. There may be false localizing signs such as 6th or 3rd nerve palsies and signs of raised ICP such as papilloedema. There may be associated focal signs and altered consciousness depending on the cause of the raised ICP. In only 20% of patients with intracranial tumours is headache the presenting feature.

The time course of the headache will depend on the cause. Acute hydrocephalus following obstruction of CSF flow can develop rapidly over hours or days. A slow-growing meningioma can produce a headache increasing over weeks or months. The headache is progressive, but does not necessarily have all the ‘classical’ features.

Idiopathic intracranial hypertension and intracranial venous thrombosis

Idiopathic intracranial hypertension (IIH) is also called benign intracranial hypertension and pseudotumour cerebri. It presents with the syndrome of raised intracranial hypertension, often with an associated machinery noise in the ears. It almost exclusively affects young obese women. The aetiology is uncertain and there are probably several causes, including tetracycline. Venous sinus thrombosis produces a similar clinical picture and is associated with the oral contraceptive pill, dehydration, clotting abnormalities and ear infections. It is diagnosed by magnetic resonance venography and treated by anticoagulation.

Diagnosis of IIH depends on demonstrating no structural cause for the raised ICP, with magnetic resonance imaging and magnetic resonance venography and measuring the increased ICP on lumbar puncture, usually over 30 cm CSF, with normal CSF constituents. The importance of the diagnosis is that, untreated, the raised ICP puts the optic nerve at risk and can result in significant visual field defects. Treatment is by lumbar puncture, acetazolamide (decreases CSF pressure) and weight loss. Visual field measurement documents progress. Occasionally, surgical drainage is required, using lumboperitoneal shunting.

Sinusitis

Tender painful sinuses, especially the frontal and maxillary sinuses, associated with fever and nasal discharge can usually be readily diagnosed. More insidious infections may present diagnostic difficulties, which may require imaging of the sinuses and ear, nose and throat (ENT) intervention. Most patients who say they get sinus headaches have migraine or cluster headache.

Arterial dissection

Carotid or vertebral dissection can present as sudden-onset neck or head pain. Carotid dissections may be associated with ipsilateral Horner’s syndrome. There may be associated stroke or transient ischaemic attacks (pp. 64–71).

Migraine and migraine with aura

Migraine is an episodic headache (Fig. 2a), associated with nausea and a dislike of light (photophobia) and sound (phonophobia). This may be preceded by focal neurological symptoms (aura). The headaches are the same regardless of the presence of the aura.

About a third of patients have premonitory symptoms for a day or so before the attack. These consist of mood swings, hunger and drowsiness.

An aura occurs in about a third of migraine patients. The aura is most commonly visual with either flashes of light or more complicated zigzag fortification spectra which shimmer and enlarge over 5–30 min. About 5% have sensory symptoms, usually paraesthesiae; others have aphasia and rarely, more complicated auras, including body distortion. Auras tend to last 10–30 min.

The headache is usually unilateral, but is bilateral in a third of cases. The pain is mainly over the temples but can affect the occipital regions. The headache is usually throbbing; it typically lasts hours, but may last days. It is usually made worse by activity and helped by sleep. The nausea associated with this can be debilitating. Surprisingly patients often report their headaches improve if they vomit. The frequency of the attacks varies widely, though medical help is usually only sought with particularly frequent or severe attacks.

The attack may be triggered by dietary factors such as cheese, chocolate, coffee or red wine. There is a significant trigger in about 20% of cases. Sleep, particularly lying in at the weekend, can also trigger attacks. Relaxation and relief of stress can be a trigger, further increasing the attacks at weekends. In women, hormonal factors seem to be important.

The oral contraceptive can trigger attacks; attacks are more common with menstruation and migraine often changes at the time of the menopause. Migraine usually improves during pregnancy.

There is usually a family history. In some rare types, such as hemiplegic migraine (where hemiplegia can follow migraine), there is a strong genetic element.

Occasionally patients may develop the migraine aura without the migraine, so-called migraine equivalents. This can cause diagnostic difficulties.

Treatment of migraine is at three levels:

Tension-type headache

Tension-type headache is the most common form of headache. The headache can be continuous or episodic and is described as pressure or a tight band around the head (Fig. 2b). The pain usually responds relatively poorly to analgesics but the patient continues to take them. The pain may be related to stress or fatigue, though can lack any clear trigger.

The pathophysiology of these headaches is not known. In spite of the frequency, the available treatments are rather disappointing. Amitriptyline is helpful, as are relaxation exercises. Helping the patient with any other associated problems may be helpful, particularly treating any coexisting migraine.

Many patients have a mixture of headaches with features of both migraine and tension-type headaches and are commonly suffering from medication overuse headaches (see below).

Medication overuse headache

Patients with chronic headache, especially migraine, often consume large amounts of analgesics or triptans. As a result they may be experiencing headaches from the withdrawal of the drug, which they then treat by further dosage, as well as their original headache type. In some patients, the original headache has resolved. Treatment is to withdraw these analgesics and try to control the headaches with prophylactic agents. Drugs particularly prone to cause misuse headaches are codeine, triptans, caffeine and paracetamol.

Trigeminal autonomic cephalalgia (e.g. cluster headache)

The trigeminal autonomic cephalalgias (TACs) are a group of uncommon headaches characterized by severe, unilateral pain, lacrimation, red eye and nasal stuffiness (Fig. 2c). They vary according to gender susceptibility, duration and treatment. The commonest is cluster headache which affects men six times more commonly than women. The bouts of severe orbital pain last from 15 min to 3 h and occasionally a ptosis and Horner’s syndrome develop. They occur frequently, once or more per day, for several weeks before subsiding to recur later, again in clusters. During the headache, the patient is restless and walks about, quite unlike a patient with migraine who will lie still. Alcohol may trigger an attack.

The acute attack can be treated with oxygen or sumatriptan by injection. Treatment to abort the cluster is preferable and steroids and verapamil are usually effective.

Other TACs are much rarer and include paroxysmal hemicrania and hemicrania continua, severe unilateral headaches with tearing and conjuctival injection, which affect women more frequently than men and respond dramatically to indometacin.

Trigeminal neuralgia

Trigeminal neuralgia is a sudden severe pain (like a red hot needle) and lasts seconds to minutes, and may be followed by a dull aching pain (Fig. 2d). It occurs in bouts, often many times each day. It can be triggered by touch, movement or cold, sometimes preventing the patient eating or drinking even to the point of dehydration. Trigeminal neuralgia is usually caused by compression of the trigeminal nerve by an ectatic blood vessel. It can also occur in multiple sclerosis.

Treatment with carbamazepine is usually effective. Oxcarbazapine, gabapentin, phenytoin and sodium valproate can also be used. If these agents are not effective, procedures that damage the trigeminal nerve such as glycerol injection, electrical lesion of the trigeminal ganglion or using the gamma knife can be effective, though all risk trigeminal sensory loss. Definitive treatment is by surgical decompression of the trigeminal nerve from the compressing vessel.

Atypical facial pain

This occurs in women. It is a unilateral, chronic, unpleasant, aching facial pain. Usually the pain is thought to come from the teeth and often patients have had unsuccessful dental procedures (including extractions). Analgesics are usually ineffective. Amitriptyline and some other tricyclics may be helpful.