Subarachnoid Hemorrhage

A 69-year-old man with an acute severe headache and nausea was brought to the emergency department. The patient was neurologically intact; an intracerebral hemorrhage was suspected. A An emergent CT scan (A), showed high-density material in the suprasellar cistern (ssc), prepontine cistern ppc), and sylvian fissures (sf). This material, which appears white on the scan, represents blood in the subarachnoid space. Enlargement of the right temporal horn (rth) indicates early hydrocephalus. An image (B) 5-mm cephalad to image A showed blood in the anterior interhemispheric fissure (aif), interpeduncular cistern (ipc), and perimesencephalic cistern pmc). An image (C) 2.3-cm cephalad of image B demonstrated enlarged, hydrocephalic ventricles (hv) and an intraventricular clot (ivc). Hemorrhage also was noted in the sylvian fissure, the pineal region (pr), the anterior interhemispheric fissure, and in a persistent cavum septum pellucidum (csp). Dr Joel Schwartz of Irvington, NY, writes that symptoms and signs of subarachnoid hemorrhage include headache, vomiting, dizziness, obtundation, syncope, seizures, cranial nerve deficits, nuchal rigidity, and low back pain. The condition usually is diagnosed by CT; small or subacute hemorrhages that are not visible on a CT scan may be diagnosed by bloody or xanthochromic cerebrospinal fluid on lumbar puncture. Trauma is the most common cause of subarachnoid hemorrhage, which is typically self-limited and resolves spontaneously. Related injuries determine treatment and prognosis. Ruptured congenital, mycotic, or arteriosclerotic aneurysms cause about 80% of nontraumatic subarachnoid hemorrhages. Other causes include arteriovenous malformations, hemorrhagic diathesis, vasculitis and, uncommonly, neoplasia. Certain diseases predispose patients to cerebral aneurysms; these conditions include polycystic kidney disease, fibromuscular dysplasia, arteriovenous malformations, connective tissue disorders, family history of intracranial aneurysm, coarctation of the aorta, and Rendu-Osler-Weber syndrome. As many as 90% of cerebral aneurysms emanate from vessels of the circle of Willis. The most common location (30%) is the anterior communicating artery, 25% are related to the posterior communicating artery, and 20% arise from the middle cerebral artery. Between 20% and 30% of patients have multiple aneurysms. Cerebral angiography is usually required to determine the source of the hemorrhage. In this patient, the angiograph revealed an anterior communicating artery aneurysm. One third of patients with ruptured aneurysms have a symptomatic warning, or sentinel, hemorrhage before a major event. However, the patient may not seek medical evaluation. About half of patients with nontraumatic subarachnoid hemorrhage die within the first few months; 50% of those who survive have major disability. Complications include rebleeding, electrolyte imbalance, hydrocephalus, and arterial vasospasm. There are various treatment approaches, including:

• Surgical clipping or endovascular closure of an aneurysm.
• Embolization, radiation, or surgery for arteriovenous malformations or tumors.
• Correction of a bleeding diathesis.
• Interventions directed at resolution of the hydrocephalus or vasospasm, if present.

This patient underwent surgical clipping of the ruptured aneurysm; he is currently recuperating.