Headache Location
Is the headache bilateral or unilateral? Unilateral head pain that alternates sides suggests migraine. Cluster headache is almost always unilateral, with the pain centered around the eye, temple, or head.
The headache of migraine can occur any-where in the head and face, with the most common site being the temple. The headache usually involves either the right or left side of the head, but it may be strictly unilateral or bilateral. The headache of tooth, sinus, or eye disease usually is frontal; but the pain may be referred to the back of the head and neck. Headaches associated with pituitary adenomas and parasellar tumors are often bitemporal.
Localized pain may occur in organic disease. The trigeminal nerve is the major source of innervation to the pain-producing structures in the supratentorial space. Infratentorial pain-producing structures receive innervation from the upper cervical, glossopharyngeal, and vagus nerves.
For these reasons, supratentorial lesions often cause frontal headaches, and those situated infratentorially often produce pain in the occipital region, although overlap in the distribution of neurons projecting to the trigeminocervical complex leads to referral outside this strict pattern. When headache is strictly limited to the periorbital region, ocular pathology should be excluded. Trigeminal neuralgia may cause pain in any area of the face that is innervated by the trigeminal nerve.
The headaches of posterior fossa tumors, early in the development of the tumor and before the beginning of general brain displacement, are usually occipital. Headaches from supratentorial tumors, before serious brain displacement occurs, are usually frontal or vertex. If the tumor involves the dura or bone, the headache may be localized to the site of the lesion. Early in the course of the tumor or before general displacement of the brain has occurred, the headache commonly is on the side of the tumor.
Subdural hematoma may produce a headache of considerable intensity, usually localized over or near the site of the lesion, most commonly over the frontoparietal areas. The headache may be chronic, daily but intermittent, and characteristically continuous from the date of injury.
Although tension-type headache may be most intense in the neck, shoulders, and occiput, it can involve the frontal region. These headaches may be unilateral or bilateral.
Disease involving the dome of the diaphragm or the phrenic nerve causes pain high in the shoulder and neck. Myocardial ischemia can cause pain in the lower jaw and cervical occipital junction.
If headache is always on the same side, should one suspect an aneurysm? What does it mean to have a persistent focal headache? Should the patient be studied? Are angiograms indicated?
Focal headaches imply focal disease. The clinician should be alert for local infection, such as sinusitis or inflammation (cranial arteritis), or diseases of the facial organs, including the eyes and nose. He or she should also be concerned about endocrine and metabolic diseases, especially diabetes. However, if the headache is typically migrainous or suggests cluster headache, then it should be accepted as such. Aneurysms are, by and large, nonpainful entities. Angiomas do not often produce pain. Angiomas may rupture, bleed, clot, calcify, provoke seizures, and eventually inhibit learning; but they do not usually hurt.
Many patients with migraine always have their headache on the same side, and there is no requirement that the headache must shift from side to side. This first maxim, then, has produced many unnecessary studies and evoked much needless worry among clinicians. If focal disease is not present, the clinician should accept the persistent repetition of unilateral throbbing head pain as compatible with headache of several types, including migraine and cluster headaches.
Editors: Silberstein, Stephen D.; Lipton, Richard B.; Dalessio, Donald J.