What is a subarachnoid hemorrhage?
Subarachnoid hemorrhage results when bleeding occurs between the brain and the meninges (the membranes that covers the brain) in the subarachnoid space. This type of hemorrhage is often due to an aneurysm or an arteriovenous malformation (AVM). An aneurysm is a weakened, ballooned area on an artery wall and has a risk for rupturing. Aneurysms may be congenital (present at birth), or may develop later in life due to such factors as hypertension or atherosclerosis. An
AVM is a congenital disorder that consists of a disorderly tangled web of arteries and veins. The cause of AVM is unknown.
In this type of brain hemorrhage, bleeding from a damaged blood vessel causes an accumulation of blood at the surface of the brain. Blood from a subarachnoid hemorrhage fills a portion of the space between the brain and the skull, and it mixes with the cerebrospinal fluid that cushions the brain and spinal cord. The large accumulation of blood acts like an enlarging mass that grows and presses on the brain, interfering with brain function. In addition, bleeding from a subarachnoid hemorrhage interrupts the vital blood supply to an area of the brain that normally is fed by the ruptured blood vessel. Most often, a subarachnoid hemorrhage happens because of a burst saccular aneurysm (a sac-like bulge in the wall of an artery), but it also can occur because of leakage from an AVM.
Subarachnoid hemorrhage is most often caused by abnormalities of the arteries at the base of the brain, called cerebral aneurysms. These are small areas of rounded or irregular swellings in the arteries. Where the swelling is most severe, the blood vessel wall become weak and prone to rupture. The cause of cerebral aneurysms is not known. They may develop from birth or in childhood and grow very slowly. Some people have not one, but several aneuryms. Subarachnoid hemorrhage can occur at any age, including teenagers and young adults. Subarachnoid hemorrhage is slightly more common in women than men.
More information on the stroke
What is a stroke? - Stroke (cerebrovascular accident) is a sudden loss of consciousness resulting when the rupture or occlusion of a blood vessel leads to oxygen lack in the brain.
What're the different types of strokes? - There are two main types of stroke. Ischemic stroke is the most common type of stroke. Hemorrhagic stroke is caused by bleeding.
What is ischemic stroke? - Ischemic stroke is the most common type. Ischemic stroke can further be divided into two main types: thrombotic and embolic.
What is a thrombotic stroke? - Thrombotic strokes are strokes caused by a thrombus (blood clot) that develops in the arteries supplying blood to the brain.
What is an embolic stroke? - Embolic strokes often result from heart disease or heart surgery and occur rapidly and without any warning signs.
What's transient ischemic attack (TIA) or mini stroke? - A transient ischemic attack (TIA) is often called a mini stroke. A transient ischemic attack (TIA) is a transient stroke that lasts only a few minutes.
What is hemorrhagic stroke? - In hemorrhagic stroke, bleeding in the brain itself or between the brain and the skull (subarachnoid hemorrhage) disrupts brain function.
What is an intracerebral hemorrhage? - Intracerebral hemorrhage is usually caused by hypertension (high blood pressure), and bleeding occurs suddenly and rapidly.
What is a subarachnoid hemorrhage? - Subarachnoid hemorrhage results when bleeding occurs between the brain and the meninges in the subarachnoid space.
What causes a stroke? - Stroke caused by damage to blood vessels in the brain. The ischemic stroke is usually caused by atherosclerosis (hardening) of blood vessels.
What are the symptoms of a stroke? - The symptoms of a stroke depend on what part of the brain and how much of the brain tissue is affected. Stroke symptoms usually come on suddenly.
What are the risk factors for a stroke? - Risk factors for a stroke include high blood pressure (hypertension), atherosclerosis, cigarette smoking, atrial fibrillation, diabetes.
How is a stroke diagnosed? - Stroke is diagnosed through several techniques: a short neurological examination, blood tests, CT scans or MRI scans, Doppler ultrasound, and arteriography.
What's the treatment for a stroke? - The aim of the therapy is to minimise the size of the stroke and therefore minimise subsequent disability by restoring blood flow to the area of the brain affected quickly.
What medications can be used for stroke treatment? - Intravenous thrombolytics. clot-busting, or thrombolytic drugs are now administered intravenously for ischemic (not hemorrhagic) stroke.
What can be done to prevent a stroke? - Prevention of stoke is an important public health concern. Medication or drug therapy is the most common method of stroke prevention.
What're the surgical treatments for stroke? - Surgical treatments for stroke include carotid endarterectomy, angioplasty, clipping. Clipping involves clamping off the aneurysm.
How to recover from a stroke? - Spontaneous recovery accounts for most improvements in the first month after a stroke. Successful recovery after a stroke depends on the extent of brain damage.
What is stroke rehabilitation? - Stroke rehabilitation is the process by which patients with disabling strokes undergo treatment to help them return to normal life.