Aneurysmal subarachnoid hemorrhage (SAH) syndrome accounts for 6 to 8 percent of all strokes, affecting approximately 28,000 individuals each year in the United States. The most common cause of spontaneous SAH is a ruptured intracranial saccular aneurysm (...Fig 22:10 ). In addition, SAH may be due to many other causes that are outlined in Table_s_2_2.-3 and 22-4. .
The clinical presentation of SAH is usually an abrupt onset of a severe headache, photophobia, nausea, vomiting, meningismus, and, often, unconsciousness and other neurological deficits (see T.a.bie 2.2.-2.). In some instances, a premonitory headache, representing a sentinel bleed, may occur days to weeks before the presenting hemorrhage. Misdiagnosis of SAH occurs in up to 25 percent of cases. y A ruptured aneurysm should be suspected in patients complaining of "sudden onset of the worst headache of my life," later onset of migraine headache with no family history of migraine, a change in the headache pattern in a known migraineur, severe localized and persistent headache, and severe "vascular" headaches that are refractory to conventional therapy.
Neurological signs are detailedin X§bJ.e 22-2 . Meningismus with nuchal rigidity and Kernig's sign is present in two thirds of patients. A dilated ophthalmologic examination may show papilledema or hemorrhages (see T.§bIe 2.2.-2 ). Ptosis or diplopia due to oculomotor nerve palsy can be seen with internal carotid-posterior communicating artery aneurysms, distal basilar aneurysm, or uncal herniation. Other neurological findings depend on the location of the aneurysm.
Clinical deterioration after SAH may be due to multiple causes, including seizures, electrolyte disturbances such as hyponatremia, cerebral vasospasm, rebleeding, hydrocephalus, and development of medical complications such as pneumonia, hypotension, electrolyte abnormalities, and cardiac arrhythmias. Diagnosis and treatment of these disorders are detailed in Part 3.
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Are Headaches Taking Your Life Hostage and Preventing You From Living to Your Fullest Potential? Are you tired of being given the run around by doctors who tell you that your headaches or migraines are psychological or that they have no cause that can be treated? Are you sick of calling in sick because you woke up with a headache so bad that you can barely think or see straight?