Lumbar puncture (LP) and spontaneous low CSF pressure headache, as elaborated in Chap. 2, is characterized by a steady occipitonuchal and frontal pain coming on within a few minutes after arising from a recumbent position (orthostatic headache) and is relieved within a minute or two by lying down. Its cause is a persistent leakage of CSF into the lumbar tissues through the needle track, or a tear of the meninges that may be spontaneous or induced by spinal trauma. The CSF pressure is low (often zero in the lateral decubitus position), and installation of an epidural “blood patch” relieves the headache. Usually this type of headache is increased by compression of the jugular veins but is unaffected by digital obliteration of the carotid artery. It is likely that, in the upright position, a low intraspinal and negative intracranial pressure permits caudal displacement of the brain, with traction on dural attachments and dural sinuses. Pannullo and colleagues, with MRI, have demonstrated this downward displacement of the cranial contents. “Spontaneous” low-pressure headache may follow a cough, sneeze, strain, or athletic injury, sometimes as a result of rupture of the arachnoid sleeve along a nerve root (see “Spontaneous Intracranial Hypotension” in Chap. 29). Less frequently, LP is complicated by severe stiffness of the neck and pain over the back of the neck and occiput (see “Lumbar Puncture Headache” in Chap. 2); a second spinal tap in some instances discloses slight pleocytosis but no decrease in glucose—a sterile meningitis. This benign reaction must be distinguished from the rare occurrence of meningitis caused by introduction of bacteria through a rent in the meninges that has allowed both escape of spinal fluid and ingress of bacteria.
Headaches that are aggravated by lying down or lying on one side occur with acute and chronic subdural hematoma and with some brain masses, particularly those in the posterior fossa. The headache of subdural hematoma, when it occurs, is dull and unilateral, perceived over most of the affected side of the head. The global and nuchal headaches of idiopathic intracranial hypertension (pseudotumor cerebri) are also generally worse in the supine position (Chap. 29). In all these states of raised intracranial pressure, headaches are typically worse in the early morning hours after a long period of recumbency. Further on, we discuss the relative infrequency of headache as a result of brain tumor.
Exertional headaches, for example those that are associated with sexual activity or weight lifting, are usually benign but they are sometimes related to pheochromocytoma, arteriovenous malformation, or other intracranial lesions, in addition to the aforementioned subarachnoid hemorrhage from ruptured aneurysm and arterial dissection. The same usually benign nature applies to headaches induced by stooping and at worst, are accounted for by sinus infection but there are exceptions and subdural hematoma is a known cause (see further on).