brain aneurysm


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aneurysm

 [an´u-rizm]
a sac formed by the localized dilatation of the wall of an artery, a vein, or the heart.
 Classification of aneurysms. All three tunica layers are involved in true aneurysms (fusiform and saccular). In false aneurysms, blood escapes between tunica layers and they separate. If the separation continues, a clot may form, resulting in a dissecting aneurysm. From Copstead and Banasik, 2000.
adj., adj aneurys´mal. The chief signs of an arterial aneurysm are the formation of a pulsating tumor, and often a bruit (aneurysmal bruit) heard over the swelling. Sometimes there are symptoms from pressure on contiguous parts.

The most common site for an arterial aneurysm is the abdominal aorta. A true aneurysm results from formation of a sac by the arterial wall with at least one unbroken layer. It is most often associated with atherosclerosis. A false aneurysm usually is caused by trauma. In this case, the wall of the blood vessel is ruptured and blood escapes into surrounding tissues and forms a clot. Because of pressure within the clot arising from the heart's contractions, the clot often pulsates against the examiner's hand as does a true aneurysm.

Although atherosclerosis is responsible for most arterial aneurysms, any injury to the middle or muscular layer of the arterial wall (tunica media) can predispose the vessel to stretching of the inner and outer layers of the artery and the formation of a sac. Other diseases that can lead to an aneurysm include syphilis, cystic medionecrosis, certain nonspecific inflammations, and congenital defects in the artery.

It is possible for a person to be unaware of a small aneurysm for years. About 80 per cent of all abdominal aneurysms are palpable and may be noticed on a routine physical examination. One should be particularly alert to the possibility of an aneurysm in persons with a history of cardiovascular disease, hypertension, or peripheral vascular disease.

Aneurysms tend to increase in size, presenting a problem of increasing pressure against adjacent tissues and organs and a danger of rupture. When an aneurysm ruptures, a critical situation ensues. The patient with a ruptured aortic aneurysm exhibits severe pain and blood loss, leading to shock. A ruptured cerebral aneurysm produces neurologic symptoms and can resemble the clinical picture of stroke syndrome.

Treatment of aneurysm depends on the vessel involved, size of the aneurysm, and general health status of the patient.
arteriosclerotic aneurysm an aneurysm arising in a large artery, most commonly the abdominal aorta, as a result of weakening of the wall in severe atherosclerosis; called also atherosclerotic aneurysm.
arteriovenous aneurysm an abnormal communication between an artery and a vein in which the blood flows directly into a neighboring vein or is carried into the vein by a connecting sac.
atherosclerotic aneurysm arteriosclerotic aneurysm.
bacterial aneurysm an infected aneurysm caused by bacteria.
berry aneurysm (brain aneurysm) a small saccular aneurysm of a cerebral artery, usually at the junction of vessels in the circle of Willis; such aneurysms frequently rupture, causing subarachnoid hemorrhage. Called also cerebral aneurysm.
cardiac aneurysm thinning and dilatation of a portion of the wall of the left ventricle, usually a consequence of myocardial infarction.
cerebral aneurysm berry aneurysm.
cirsoid aneurysm dilatation and tortuous lengthening of part of an artery; called also racemose aneurysm.
compound aneurysm one in which some of the layers of the wall of the vessel are ruptured and some merely dilated; called also mixed aneurysm.
dissecting aneurysm one resulting from hemorrhage that causes lengthwise splitting of the arterial wall, producing a tear in the inner wall (intima) and establishing communication with the lumen of the vessel. It usually affects the thoracic aorta (see aortic dissection) but can also occur in other large arteries. See illustration.
false aneurysm
one in which the entire wall is injured and the blood is contained by the surrounding tissues, with eventual formation of a sac communicating with the artery (or heart). See illustration.
fusiform aneurysm a spindle-shaped aneurysm; see illustration.
infected aneurysm one produced by growth of microorganisms (bacteria or fungi) in the vessel wall, or infection arising within a preexisting arteriosclerotic aneurysm.
mixed aneurysm compound aneurysm.
mycotic aneurysm an infected aneurysm caused by fungi.
racemose aneurysm cirsoid aneurysm.
saccular aneurysm (sacculated aneurysm) a saclike aneurysm; see illustration.
spurious aneurysm
false aneurysm (def. 1).
varicose aneurysm one formed by rupture of an aneurysm into a vein.

cerebral aneurysm

A dilated and weak segment of a cerebral artery, often located in the circle of Willis at the base of the brain, which is susceptible to rupture; cerebral aneurysms may be birth defects or follow poorly controlled hypertension.

Clinical findings
“Thunderclap headache” often associated with nausea, vomiting and reduced consciousness.

brain aneurysm

Cerebral aneurysm Neurology A dilated and weak segment of a cerebral artery, often located in the circle of Willis at the base of the brain, which is susceptible to rupture; BAs may be caused by birth defects or follow poorly controlled HTN Clinical “Thunderclap headache” often associated with N&V, ↓ consciousness

Patient discussion about brain aneurysm

Q. Could I be going through a Brain aneurysm? i woke up in the night with a bad headache in the back of my head and above my eye. never had a headache like that. but all day today have not had the headache. could this be an aneurysm?

A. I had an brain anyuism in 2001. I had a head ache right above my left eye for 10 days. It got worse as the days went by. I went in to the emergency room and they gave me a spinal tap and it ruptured.Thank God that it cloted (that dos'nt happen). But it did and they did emergency surgury. I am alive and back to normal today. My parents both died of brain anyuisms. That is how huretaty starts.

Q. Can I have a MRI of the knee if I have hemostatic clips in the brain?(also called aneurysm clips)?

A. How about a CAT scan of the knee?, I wonder if it would be an appropriate diagnostic tool, I suspect problems with a lateral meniscus.

More discussions about brain aneurysm
References in periodicals archive ?
Despite suffering a brain aneurysm in April, she returned to work after being dearly missed by children and colleagues.
According to a report published May 22,2014 in the journal Stroke, they found that over a lifetime, approximately one-third of all brain aneurysms eventually ruptured, including about 25 percent of smaller aneurysms.
She had a brain aneurysm and I almost pulled out of the Olympics.
The Basic Instinct star suffered a health scare in 2001 when she was hospitalised for a brain aneurysm - bleeding in the brain that can cause strokes - after suffering severe headaches.
Following his admission Dr Al Samaheeji a scan for his brain was administered that reveal him internal hemorrhage and was diagnosed as suffering healed brain aneurysm.
Women are more likely to develop a brain aneurysm after 40 and the bulge is most likely to rupture between the ages of 50 and 59.
The 41-year-old mum-oftwo said undergoing emergency surgery for a potentially fatal brain aneurysm four years ago was enough to put her off facing any kind of procedure just to maintain her looks.
If you have a bicuspid aortic valve (BAV), meaning the valve did not fully develop into having three leaflets, recent research indicates that you may have a higher risk for a brain aneurysm. A study in the May 4 issue of the journal Neurology found a significantly higher risk of a brain aneurysm among people with a two-leaflet aortic valve, instead of the more common three-leaflet valve.
A WIRRAL councillor found dead at her home suffered a ruptured brain aneurysm.
KARACHI, November 12, 2009 (Balochistan Times): Neurosurgeon at Jinnah Post Graduate Medical Centre here on Thursday successfully performed the first non - invasive surgery to correct Brain Aneurysm at any of the public sector facilities of the country.
WHEN Georgie Hugill collapsed with a ruptured brain aneurysm she was given just a 1% chance of survival.
"From Darkness to Light: My Journey Back from a Brain Filled with Blood" is the story of Lynn Christopher Roby and her recovery from a severe brain aneurysm that nearly took her life.