The Same, Only Different
The patient, a 32-year-old nurse, had suffered from recurrent headaches every few months since childhood. These were generally of a pulsating quality, very intense, and limited to one side of the head, usually the right side. The pain was most intense behind the eye, accompanied by a strong sensation of pressure. Each attack lasted 6 to 8 hours; during the attacks, she was also very sensitive to light and noise. Whenever possible, she withdrew to a quiet, dark room, avoided all activity, and waited for the pain to go away. Her mother had suffered from similar headaches.
She had a severe headache again one Easter Sunday; this surprised her, because the last attack had been only 1 week before. This time, the pain came on not gradually, but suddenly, “out of a clear blue sky,” and was much more intense than usual. The pain was “all over my head,” and she felt as if her head were about to explode. She went to her room and lay down. Five minutes later, she became nauseated and vomited repeatedly. Over the next half hour, she became progressively confused. Her husband called the emergency medical services.
This patient’s prior usual headaches were typical migraine headaches, but the Easter Sunday episode was of another kind entirely. A headache of sudden onset and extreme intensity is characteristic of an intracranial hemorrhage. The most common cause is a ruptured aneurysm of an artery at the base of the brain, causing arterial blood to enter the subarachnoid space (subarachnoid hemorrhage, SAH).
The emergency physician on the scene examined her and found meningismus (a clinical manifestation of leptomeningeal irritation, generally caused either by extravasated blood or by an infectious/inflammatory process). She was somnolent, but responsive and cooperative, and had no other neurologic deficits. Suspecting SAH, the emergency physician had her transported immediately to the emergency room of a tertiary-care hospital for neurosurgical evaluation. A computed tomography (CT) scan confirmed the diagnosis of SAH and revealed a probable ruptured aneurysm of the anterior communicating artery as the cause. This was then confirmed by angiography, whereupon the aneurysm was obliterated with intravascular detachable coils in an interventional neuroradiologic procedure.
Headache is a common symptom in everyday clinical practice and has many causes. Primary diseases of the nervous system often cause intense or unbearable pain as a prominent or even sole manifestation. For this reason, neurologists are often consulted to help in the evaluation of patients with pain. The nervous system plays a key role in the transmission and processing of nociceptive impulses and in the perception of pain.
Many conditions whose most prominent, or sole, symptom is pain lie within the neurologist’s field of expertise. In this chapter, we will discuss painful syndromes by location: headache, facial pain, shoulder–arm pain, pain in the trunk, and pain in the lower limb. The differential diagnosis of a painful syndrome cannot be restricted to neurologic conditions and must always include diseases of nonneurologic origin.
14.1.1 The Generation and Perception of Pain
Pain is a type of unpleasant sensation. In terms of pathophysiology, it arises when specialized sensory end organs are excited by certain mechanical, thermal, or chemical stimuli of a potentially damaging (“noxious”) nature. The pain-related (“nociceptive”) impulses are conducted centrally, mainly by way of thin, poorly myelinated fibers, through the posterior root and into the spinal cord. The nociceptive fibers cross the midline in the spinal cord at their level of entry and then ascend in the spinothalamic tract to the thalamus and onward to higher centers in the brain, which enable pain to be consciously felt (see section ▶ 5.3 and ▶ Fig. 5.2). Biochemical factors also play an important role in pain perception. In the periphery, the intensity of pain is increased by a variety of biogenic amines, for example, substance P. In the central nervous system, the intensity of pain is modulated by the production of opioid substances in certain areas of the brain. Finally, psychological factors—relating to the patient’s personality as well as the sociocultural environment—affect the manner in which pain is experienced and processed.
14.1.2 General Aspects of the Clinical History in Patients with Pain
Many painful syndromes have their origin in the nervous system; many others, in which there is no evident neural dysfunction (e.g., most kinds of headache), are nonetheless traditionally evaluated and treated by neurologists. These facts justify the inclusion of painful syndromes in a textbook of neurology. It should be emphasized, however, that the physician confronted by the symptom “pain” should not approach it from the narrow viewpoint of any particular specialty, but must rather apply the full range of general medical knowledge.
This purpose is best served, first, by the taking of a systematic and directed pain history. The main elements of the pain history are listed in ▶ Table 14.1. Further specific questions will need to be asked depending on the nature and location of pain in the particular case, and ancillary diagnostic tests may be needed as well.
Where is the pain?
How long has it been present?
Continuous or intermittent?
Precipitating and/or aggravating factors?
How severely is the patient impaired by the pain?
Current complaints other than pain?
In the remainder of this chapter, we will discuss various major painful syndromes, classifying them by location.
14.2 Painful Syndromes of the Head and Neck
Headache can be either idiopathic or symptomatic. The most common idiopathic or “primary” types of headache are tension-type headache, migraine, and cluster headache. While migraine and cluster headache are typified by highly characteristic, mostly unilateral attacks of pain, tension-type headache more commonly assumes the form of a diffuse, continuous headache of lesser intensity. Symptomatic (“secondary”) headaches are, by definition, a manifestation of some other underlying condition. The possible causes include many neurologic diseases, as well as diseases of the eyes, teeth, jaw, ear, nose, and throat, and many general medical conditions. Spondylogenic headache is caused by pathologic processes in the cervical spine. A third group of conditions characterized by head and neck pain is the neuralgias, the most common of which is trigeminal neuralgia.
Headache can also include a variably significant component of facial pain—a typical example is cluster headache, which is felt mainly in the forehead, eye, and temple. Headache and facial pain cannot be cleanly separated from each other and are therefore considered under one heading in the International Headache Society (IHS) classification (see later and also ▶ Table 14.2). It is nonetheless useful, for clarity, to distinguish syndromes in which the pain is mainly in the head from those in which it is mainly in the face. Headache will accordingly be discussed in this section and facial pain in the next.
Cranial neuralgias, central and primary facial pain, and other headaches
Note: Further subcategories and related information can be found on the Web site of the International Headache Society (ihs-classification.org).
14.2.1 IHS Classification of Headache
The classification of headache syndromes proposed by the IHS has won general acceptance. The major categories of headache in this system are listed in ▶ Table 14.2. The IHS has established obligatory diagnostic criteria for each type of headache. This highly precise approach to headache syndromes is most useful in clinical research, where the findings of different teams of investigators must be compared with each other, but it is also highly practical for routine clinical use.
The potential benefit of any proposed treatment of a particular type of headache can only be assessed reliably when it is clear that all of the research teams reporting on it are, in fact, treating the same condition. Standardization is the main virtue of the IHS criteria.
For the beginning student of neurology, however, it is more useful to gain a descriptive overview of the more common, “classic” types of headache ( ▶ Table 14.3). In particular, he or she should learn to distinguish the common primary types of headache, that is, those not due to any demonstrable structural lesion in the head, from secondary types. The latter are caused by organic disease of the cranial vessels or other structures in the head, or have other organic causes (e.g., infection, disorders of homeostasis). Ninety percent of all cases of headache are of the primary type.
Site of pain
Duration of episodes
Frequency of episodes
Phenomena during episodes
Intensity; other remarks
Hours to days
Rare to several times per week
No unusual phenomena
Two-thirds of attacks are unilateral, one-third bilateral
Rare to several times per week
Occasionally, Horner syndrome
Periorbital, forehead, temple, maxilla
Horner syndrome, periorbital erythema, conjunctival injection, lacrimation, rhinorrhea or stuffed nose
In the distribution of one of the three divisions of CN V (usually maxillary)
Fraction of a second
1 to 100 per day
Painful contraction of the affected half of the face (tic douloureux)
Secondary headache types
Depends on etiology
Usually continuous or long-lasting
Depends on etiology
Abbreviation: CN, cranial nerve.
14.2.2 Approach to the Patient with Headache
The patient who goes to the doctor because of headache is suffering from pain and, often, anxiety. He or she therefore can rightly expect the following:
To be taken seriously.
To be examined carefully.
To have the cause of the problem identified and clearly explained.
To be given effective treatment.
The physician must take the time needed to meet these expectations fully.
The clinical history is a vital step in the evaluation of headache. The systematic interview of the headache patient should address the following points:
Family history of headache?
How long have headaches been present?
Nature of headache:
Continuous or episodic?
Usual or unusual quality of pain?
Timing of onset?
Speed of development?
Character of pain?
Duration of episodes?
Impairment of activities at home and at work?
Drugs and other measures against headache:
Other symptoms besides headache:
ENT, ophthalmic, or dental disease?
General symptoms (fatigue, weight loss, circulatory problems, etc.)?
Personality and external circumstances:
Alcohol, tobacco, caffeine, drugs of abuse?
A carefully elicited history usually leads to a fairly secure diagnosis. Nonetheless, the general physical examination and the neurologic examination should never be omitted, not least because they help the physician win the patient’s confidence—an important factor for the success of treatment. The examination should include the following:
General medical examination:
Cardiovascular system, especially blood pressure.
Signs of infection.
Signs of meningitis.
Signs of malignancy.
Dental diseases, jaw diseases.
Neurologic examination, with particular attention to:
Signs of intracranial hypertension.
Focal neurologic signs.
Cranial nerve deficits.
Mental status, with particular attention to:
Impairment of consciousness.
Current psychological conflicts.
Neurotic personality traits.
14.2.3 The Main Types of Primary Headache
Definition and frequency By definition, primary headache is not a symptom or consequence of any other disease—the pain itself is the disease. About 60 to 70% of people suffer from headache or facial pain at some time in their lives, but only about 15% seek medical attention. Of people with headaches, 90% have one of the two most common types: tension-type headache and migraine.
Pathogenesis Multiple factors probably play a role in the pathogenesis of tension-type headache and, especially, migraine ( ▶ 22.214.171.124). Positron emission tomography (PET) studies have revealed activation in the brainstem at the beginning of a migraine attack and in the hypothalamus in cluster headache. In a migraine attack, there is first vasoconstriction, then vasodilation. Dilation of the large arteries of the base of the brain is usually accompanied by unilateral, often throbbing headache. Vasodilation was once thought to cause the headache but is now thought to be an epiphenomenon, that is, a result of the same activation of the trigeminovascular system that separately causes headache. Migraine is presumably initiated when a neural process that is not yet completely understood activates the trigeminovascular system, leading to pain. The dura mater, the large arteries of the base of the brain, and the pial vessels all receive sensory innervation from the trigeminal nerve and the gasserian (trigeminal) ganglion. The main function of the sensory trigeminal system is to protect the head from dangerous external influences and stimuli. The pain that arises in primary headache syndromes is of no use to the organism and is thought to be caused by faulty activation of the system.
These changes in the trigeminovascular system are partly caused, or accompanied, by changes in humoral mediators. The neurotransmitter serotonin plays an especially important role, and several vasodilator peptides have been discovered in trigeminal neurons, including substance P, neurokinin A, and the calcitonin gene–related peptide. Antagonists of these peptides, and antibodies against them, are now being tested as drugs for the prevention and treatment of migraine attacks.
Tension-type headache has episodic and chronic forms.
In the IHS classification, sporadic episodic tension-type headache (of greater or lesser frequency) is defined as follows:
A: At least 10 previous episodes (once per month or on at least 12 days per year, or else on more than 1 but fewer than 15 days per month) that met criteria B to D and were present on fewer than 180 days per year overall.
B: Each individual headache episode lasts for 30 minutes to 7 days.
C: The pain is characterized by at least two of the following features:
Pressing, squeezing, not throbbing.
Of mild to moderate intensity.
Not exacerbated by physical activity, walking, or climbing steps.
D: Both of the following criteria must be fulfilled:
No nausea or vomiting
No photophobia or photophobia, or at most one, but not the other.
E: The headache is not due to any other known disease.
Tension-type headache is illustrated schematically in ▶ Fig. 14.1.
Fig. 14.1 Tension-type headache. (These images are provided courtesy of Mumenthaler M, Daetwyler Ch, Kopfschmerz Interaktiv, Instructional Media Department [AUM-IAWF] of the University of Bern Faculty of Medicine, 2001.)
Chronic tension-type headache occurs, by definition, on more than 15 days per month for at least three consecutive months and on at least 180 days per year. The pain is usually diffuse, sometimes felt most intensely on the forehead, temples, or vertex, and often of a dull rather than throbbing character. It does not worsen with exercise. It can arise at any time of day, but most often in the morning on awakening or shortly after the patient gets up. There are usually no accompanying symptoms. This type of headache mainly affects young or middle-aged persons, men just as commonly as women, although the subjective suffering of female patients tends to be worse. The headaches are often provoked by weather changes, sleep deprivation, overconsumption of alcohol (“hangover headache”), and emotional tension. The neurologic examination reveals no abnormalities.
Treatment The main components of treatment are:
Dealing with external and internal sources of emotional tension.
On the pharmacologic level of attack management, acetaminophen 1,000 mg, ibuprofen 200 to 600 mg, or a combination of acetylsalicylic acid 250 mg, acetaminophen 250 mg, and caffeine 50 mg. Excessive intake of drugs to treat chronic tension-type headache can cause medication-overuse headache (see section ▶ 14.2.4, ▶ 126.96.36.199).
Important prophylactic measures include relaxation exercises (e.g., progressive muscle relaxation by the Jacobson’s technique), endurance training, and stress-management training, ideally in a multidisciplinary treatment program. Acupuncture does not lessen the frequency of attacks of episodic tension-type headache. Antidepressants (e.g., amitriptyline) can be considered for patients with the chronic form of the disorder.
Migraine, a type of primary headache, is the second most common type of headache overall, after tension-type headache (see earlier). It is characterized by intense, often hemicranial headaches that last several hours, occur at variable frequency, and are accompanied by nausea (and sometimes vomiting), photophobia, and phonophobia. The pain worsens with physical activity. The first headaches often occur in the patient’s teens. Migraine is markedly more common in women than in men.
Pathogenesis The pathogenesis of migraine is discussed more extensively earlier at the beginning of this section.
Epidemiology The frequency of migraine in schoolchildren is generally estimated at 5%. Among older children, it affects girls more commonly than boys.
In adults, epidemiologic studies have revealed an unexpectedly high prevalence of migraine, roughly 25% in women and 17% in men. More than half of all “migraineurs” have a family history of headache (not necessarily of typical migraine). Women are more commonly affected, or, at least, they more commonly seek medical help.
Simple (Classic) Migraine without Aura
Clinical features Migraine without aura (also called simple, classic, or common migraine), whose sole neurologic manifestation is headache, is distinguished from migraine with aura (also called complicated migraine), in which additional neurologic manifestations are present. The IHS criteria for the diagnosis of migraine without aura are as follows:
A: The patient has had at least five attacks fulfilling criteria B to D.
B: The attacks last 4 to 72 hours (if untreated or unsuccessfully treated).
C: The headache has at least two of the following features:
Moderate or marked intensity.
Worsening when the patient walks, climbs stairs, or performs similar everyday physical activities, which are avoided.
D: At least one of the following symptoms is present during the headache:
Nausea and/or vomiting.
Oversensitivity to light and noise.
E: The headaches are not attributable to any other disease.
Persons with migraine have often had uncharacteristic headache attacks in their childhood. They suffer from episodic abdominal pain and vomiting appreciably more frequently than the general population. Episodic headaches that only arise in adulthood are truly “hemicranial” in only about 65% of cases. The pain is often described as throbbing, pulsating, piercing, and deep; it worsens with any kind of physical exertion, even as mild as climbing a staircase, and with external stimuli such as light and noise. It reaches maximum intensity within 1 hour or a few hours, and 60% of patients have nausea and/or vomiting. Because of their oversensitivity to light and noise, patients usually withdraw to a dark and quiet room during the attack. They often cannot tolerate odors either. Allodynia, that is, pain felt merely on light touch of certain areas of the skin, has been described as occurring in 70% of patients during attacks. In many patients, the attacks are almost always on the same side of the head, but absolute constancy of the affected side should arouse suspicion of secondary headache. The attacks generally last at least 1 hour and may last for many hours; their frequency varies from a few per year to several per week. The typical features of migraine are shown schematically in ▶ Fig. 14.2.
Fig. 14.2 Migraine attack. (These images are provided courtesy of Mumenthaler M, Daetwyler Ch, Kopfschmerz Interaktiv, Instructional Media Department [AUM-IAWF] of the University of Bern Faculty of Medicine, 2001.)
Chronic migraine is defined as consisting of attacks that occur on more than 15 days per month for at least three consecutive months. An intense migraine attack that lasts longer than 72 hours is called status migrainosus. An aura without headache can also last a week or more. (For migraine auras, see the next subsection.)
Precipitating factors Common triggers are emotional stress (responsibilities, worries, excessive demands, tension) or, alternatively, diminishing stress and prolonged lying in bed (Sunday or holiday migraine). Further possible precipitating factors are weather changes and photic stimuli (e.g., bright sunlight). In women, migraine attacks may regularly come just before, or at the same time as, menstruation. Certain substances in food, such as chocolate or aspartame, can also precipitate migraine in some persons. The pressor substance tyramine, which is found in certain kinds of cheese, is a rare migraine trigger; it can also cause hypertensive crises in patients taking monoamine oxidase inhibitors. Migraine induced by trauma (“footballer’s migraine”) has been described as well.
Diagnostic evaluation In persons with classic migraine, the neurologic examination is normal. The electroencephalogram (EEG) may show nonspecific changes, usually slow waves.
Treatment The treatment of common migraine depends on the frequency and severity of the attacks.
Rare and mild attacks often need no treatment. Moderately severe, not very prolonged attacks that are relatively rare (occurring less than three times per month) can be managed by treating the individual attacks. Mild to moderate attacks can be effectively treated early on in each attack with analgesic drugs or nonsteroidal anti-inflammatory drugs (NSAIDs) in adequate doses, for example, acetylsalicylic acid 1,000 mg, acetaminophen 1,000 mg, ibuprofen 200 to 600 mg, or the fixed combination of acetylsalicylic acid 250 mg, acetaminophen 250 mg, and caffeine 40 mg. For nausea, an antiemetic drug should be given as well, for example, metoclopramide 20 mg by mouth or, if necessary, as a suppository. Moderate to severe attacks are often treated with triptans (usually by mouth); many patients prefer triptans because they are more effective than the analgesics and relieve pain faster. They are also more effective than ergotamines, which should no longer be given because of their side effects.
The available triptan preparations differ in the strength and latency of pain relief and in their side effects. If necessary, a triptan can be given by injection (sumatriptan) or as a nasal spray (sumatriptan, zolmitriptan). The oral triptans that relieve pain fastest are rizatriptan and eletriptan.
If the attacks occur more than three times per month and/or severely hamper the patient’s everyday activities because of their duration (>72 hours) or severity, attack prophylaxis should be given. Once begun, this must usually be maintained continuously for months (rarely, years) afterward. First-line drugs for attack prophylaxis are the β-blockers propranolol and metoprolol, the anticonvulsants topiramate and valproate, and the calcium antagonist flunarizine. Second-line drugs include antidepressants (amitriptyline, venlafaxine), gabapentin, naproxen, acetylsalicylic acid, and magnesium. These recommendations also apply to the various types of complicated migraine described later.
Migraine with Aura
More than one-third of all persons with migraine suffer from other neurologic manifestations before the headache itself begins, for example, visual or sensory disturbances, difficulty speaking, paralysis, vertigo (see section ▶ 12.6.2, ▶ Vestibular Migraine), or abdominal symptoms. This condition is called migraine with aura or, in the traditional nomenclature, complicated migraine.
Migraine auras develop over 5 to 20 minutes and end within 60 minutes at most. They can be very dramatic, sometimes overshadowing the headache to such an extent that the patient’s illness is not immediately recognizable as migraine. In pathophysiologic terms, auras have been correlated with the phenomenon of spreading depression (of Leão), a wave of cortical neuronal discharge followed by neuronal silence that begins in the visual cortex and sweeps outward. Regional cerebral blood flow decreases during an aura and increases afterward.
Sometimes, an aura can be the only symptom of a migraine attack. This is called a typical aura without headache (or, traditionally, “migraine sans migraine”).
We will now individually describe the major clinical types of migraine with aura.
Migraine with ophthalmic aura This is characterized by visual symptoms that precede the headache. About one-third of persons with migraine have ophthalmic auras. The typical kind is a scintillating scotoma, that is, a flashing figure bordered by a bright, zigzag line (“fortification figure”—think of a crenellated medieval fortress), which is seen in both eyes. It arises in the center of one visual hemifield and then travels outward for 5 to 15 minutes until it falls out of view in the periphery, leaving behind a transient impairment of vision in the hemifield ( ▶ Fig. 14.3). The scintillating scotoma is followed by an attack of hemicranial headache, usually on the opposite side. Occasionally, no headache follows (migraine sans migraine); patients with this type of migraine may have a permanent visual field defect. There are also rare cases in which the visual disturbance affects one eye only (retinal migraine).
Fig. 14.3 Scintillating scotoma during an attack of ophthalmic migraine: typical fortification figures.
Ophthalmoplegic migraine This is defined as a migraine-like headache accompanied by ipsilateral weakness of the extraocular muscles, usually due to oculomotor nerve palsy. The existence of this type of membrane is questionable. Other causes of ophthalmoplegia must be ruled out.
An aura consisting of a hemisensory deficit or aphasia, previously called migraine accompagnée, now appears in the IHS classification under the heading typical aura with migraine headache. This variant of migraine usually begins in childhood or adolescence. In an attack, paresthesia arises in a small area, most often on an arm or the face, spreads within a few minutes to cover a larger area (e.g., from the thumb to the entire arm to the face), and then slowly subsides. Aphasia may follow or may be the sole manifestation of the aura. The typical hemicranial headache usually comes after the neurologic disturbance, on the same or the opposite side, enabling the diagnosis of migraine to be made. Headache may also be absent, in what is called aura without headache (traditionally, migraine accompagnée sans migraine); this type of migraine is especially common in children and is the initial manifestation of migraine in nearly half of all cases.
An EEG recorded after an aura shows a focal abnormality that may take a few days to resolve. Attacks may also be accompanied by cerebrospinal fluid (CSF) pleocytosis. CSF pleocytosis or auras without headache call for careful diagnostic evaluation to rule out other potential causes of the problem, for example, transient ischemia.
Familial hemiplegic migraine (FHM) This is characterized by recurrent migraine attacks accompanied by a transient hemiparesis, hemiplegia, or hemisensory deficit that resolves within 1 hour. Most patients have, or had, a first- or second-degree relative with the same disorder. There are multiple genetic subtypes. FHM1 is due to a mutation in the CACNA1A gene on chromosome 19, while FHM2 is due to a mutation in the ATP1A2 gene on chromosome 1.
Basilar migraine In this type of migraine, the symptoms reflect a pathophysiologic process located in both cerebral hemispheres as well as the brainstem. The name of the disorder reflects an earlier belief that the underlying abnormality was limited to the distribution of the basilar artery, which may not be true. The symptoms of the aura include varying combinations of dysarthria, dizziness, tinnitus, hearing loss, double vision, and ataxia, and, typically, simultaneous bilateral paresthesia and visual impairment in both hemifields of both eyes. Consciousness is variably impaired, to an extent ranging from somnolence to coma. The patient may be confused during the attack and amnestic for it afterward. The headache is generally occipital. Basilar migraine mainly affects girls and young women.
Special types of migraine with aura These include abdominal migraine, which is not uncommon, mainly in children, and cyclic vomiting syndrome; both of these disorders are often a precursor of migraine (i.e., headache develops later). Adults with migraine may have accompanying psychiatric manifestations such as mood swings (anxiety, depression), cognitive disturbances, confusion, agitation, or even “migraine psychosis” (dysphrenic migraine). Recurrent attacks of dizziness, termed vestibular migraine (see section ▶ 12.6.2, ▶ Vestibular Migraine), have also been described; other syndromes in this class include benign paroxysmal vertigo of childhood and episodic ataxia (cerebellar migraine).
Treatment of migraine with aura Migraine with aura is treated in the same way as simple migraine (see earlier).
Cluster Headache and Other Trigeminal Autonomic Cephalalgias
The category called “trigeminal autonomic cephalalgias” in the new IHS classification comprises pain syndromes that mainly affect the face and have accompanying autonomic manifestations, for example, conjunctival injection, facial erythema, lacrimation, and altered nasal secretion ( ▶ Table 14.4). All of them are of a more or less paroxysmal nature, with short-lasting individual attacks of pain. They are as follows:
Site of pain
Duration of attacks
Frequency of attacks
Phenomena during an attack
Periorbital, frontal, temporal, maxillary
Horner syndrome, conjunctival injection, tearing, runny or stuffed nose, periorbital edema
Always on the same side
Conjunctival injection, tearing, runny or stuffed nose, eyelid edema, sweating, Horner syndrome
Responds to indomethacin
At least 15 min
>15 nights per month
Headaches awaken patient from sleep, onset after age 50, considered a rare type of primary headache
5 s to 5 min
≥100 per day
Conjunctival injection, tearing
Must be distinguished from cluster headache and trigeminal neuralgia
Distribution of one branch of the trigeminal nerve (usually maxillary)
A few to 100 per day
Painful contraction of the affected side of the face
Usually idiopathic in older patients, often symptomatic in younger ones
Abbreviation: SUNCT, short-lasting unilateral neuralgiform headache with conjunctival injection and tearing.
Epidemiology Cluster headache (older, alternative name: “Bing–Horton neuralgia”) is about 1/10 as common as migraine. Unlike migraine, it is much more common in men, particularly smokers. It often begins in middle age or old age.
Pathogenesis and etiology Cluster headache attacks tend to occur in a circadian rhythm. The disorder is attributed to a functional disturbance of the diencephalon, as PET studies have shown increased activity in the hypothalamus during the attacks. Individual attacks can be induced by alcohol, histamine, or nitroglycerin. Aside from primary cluster headache, there are also symptomatic forms, caused, for example, by mass lesions.
Clinical features These are highly typical and are illustrated in ▶ Fig. 14.4.
Fig. 14.4 Cluster headache attack. (These images are provided courtesy of Mumenthaler M, Daetwyler Ch, Kopfschmerz Interaktiv, Instructional Media Department [AUM-IAWF] of the University of Bern Faculty of Medicine, 2001.)