Table - 1: Characteristics of Common Headache Syndromes

Symptom Migraine headache Tension headache Cluster headache Location Unilateral in 60 to 70 Bilateral Always unilateral, usually percent; bifrontal or begins around the eye or global in 30 percent temple Characteristics Gradual in onset, Pressure or tightness Pain begins quickly, crescendo pattern, which waxes and reaches a crescendo pulsating; moderate wanes within minutes; pain is or severe intensity; deep, continuous, aggravated by routine excruciating, and explosive physical activity in quality Associated Nausea, vomiting, None Ipsilateral lacrimation and photophobia, phono- redness of the eye; stuffy phobia; may have aura. nose; rhinorrhea; pallor sweating; Horner's syndrome focal neuro logic symptoms rare; sensitivity to alcohol


• Possible association with environmental factors

• Effects of menstrual cycle (women)

Characteristics of Headache with Serious Underlying Pathology

There are an important sequence of questions on the history and findings on the physical examination that help to distinguish potentially serious from benign headache. An algorithm to guide the evaluation of the patients with dull headache is shown in Figures 1 and 2.

History

The following features in the history serve as warning signs of possible serious underlying disease: Sudden onset _ Severe persistent headache which reaches maximal intensity within a few seconds or minutes after the onset of pain warrants aggressive investigation. Subarachnoid hemorrhage, often presents with the abrupt onset of excruciating pain. In contrast, migraine headaches generally begin with moderate pain and then gradually increase to a maximal level over one to two hours. No similar headaches in the past _ The absence of similar headaches in the past is another finding that suggests a possible serious disorder. The "first" or "worst" headache of my life is a description that sometimes accompanies an intracranial hemorrhage or central nervous system (CNS) infection. On the other hand, patients suffering from migraine usually have had similar types of headaches in the past. Concomitant infection _ Infection in a non-intracranial location (such as the lungs or paranasal or mastoid sinuses) may serve as a nidus for the development of meningitis or intracranial abscess. Fever is not a characteristic of migraine headache; it may, however, follow a subarachnoid hemorrhage by a few days.

Altered Mental Status: Any change in mental status, personality, or fluctuation in the level of consciousness suggests a potentially serious abnormality.

Headache with Vigorous Exercise: The rapid onset of headache with strenuous exercise, especially when minor trauma has occurred, raises the possibility of carotid artery dissection or intracranial hemorrhage.

Location of Pain: Head pain that spreads into the lower neck and between the shoulders may indicate meningeal irritation due to either infection or subarachnoid blood; it is not typical of a benign process.

Physical Exam

The following findings on physical examination may suggest a life-threatening CNS cause of the headache:

Nuchal Rigidity: Nuchal rigidity may indicate meningitis or subarachnoid hemorrhage.

Toxic Patient: A toxic appearing patient may be suffering from a systemic illness affecting the CNS. A low grade fever or persistent tachycardia may also indicate an underlying infection.

Neurologic Abnormalities: The patient with any new focal neurologic abnormality must be evaluated for serious illness. Neurologic abnormalities can also occur with migraine. However, they usually consist of symptoms (something reported by the patient but not observable) but not signs (an observable deficit). Furthermore, migraines have usually occurred in the past and symptoms persist for less than 60 minutes. A focal neurologic sign is not typical of migraine and should be investigated. Decreased level of consciousness _ Obtundation and confusion increase the likelihood of meningitis, encephalitis, subarachnoid hemorrhage, or other space occupying lesion. Papilledema _ Papilledema, detected by blurring of the optic disks, is indicative of increased intracranial pressure, possibly due to a tumor or other structural abnormality.