Aneurysm in the brain

Answer 1

Definition

An aneurysm is an abnormal widening or ballooning of a section of a blood vessel. When an aneurysm occurs in the brain, it is called a cerebral aneurysm.

Alternative Names

Aneurysm - cerebral; Cerebral aneurysm

Causes, incidence, and risk factors

Aneurysms in the brain occur when there is a weakened area in the wall of a blood vessel. An aneurysm may be present from birth (congenital) or it may develop later in life. (For example, after a blood vessel is injured.)

There are many different types of aneurysms. A berry aneurysm can vary in size from a few millimeters to over a centimeter. Giant berry aneurysms can reach well over 2 centimeters. These are more common in adults. Multiple berry aneurysms are inherited more often than other types of aneurysms.

Other types of cerebral aneurysm involve widening of an entire blood vessel, or they may appear as a "ballooning out" of part of a blood vessel. Such aneurysms can occur in any blood vessel that supplies the brain. Trauma and infection, which can injure the blood vessel wall, can cause such aneurysms.

About 5% of the population has some type of aneurysm in the brain. Risk factors include a family history of cerebral aneurysms, and certain medical problems such as polycystic kidney diseaseand coarctation of the aorta.

Symptoms

Aneurysms usually cause no symptoms unless they rupture and cause bleeding into the brain. Often, an aneurysm is found when a CT scan or MRI is performed for another reason. Symptoms occur if the aneurysm pushes on nearby structures in the brain.

Symptoms depend on what structure the aneurysm pushes on, but may include:

• Double vision
• Loss of vision
• Headaches
• Eye pain
• Neck pain

A sudden, severe headache (often described as "the worst headache of your life") is one symptom that an aneurysm has ruptured. Other symptoms of an aneurysm rupture may include:

• Confusion, lethargy, sleepiness, or stupor
• Eyelid drooping
• Headaches with nausea or vomiting
• Muscle weaknessor difficulty moving any part of the body
• Numbness or decreased sensationin any part of the body
• Seizures
• Slow, sluggish, lethargic movement
• Speech impairment
• Stiff neck (occasionally)
• Sudden onset of irritability, impulsivity, or poor temper control
• Vision changes (double vision, loss of vision)

NOTE: A ruptured aneurysm is a medical emergency. Seek immediate medical help.

Signs and tests

An eye exam may show increased pressure within the brain (raised intracranial pressure), including swelling of the optic nerve or bleeding into the retina of the eye.

The following tests may be used to diagnose cerebral aneurysm and determine the cause of bleeding within the brain:

• CT scan of the head
• CSF exam(spinal tap)
• MRI of the head(CT scans may be better at showing bleeding in the brain)
• Cerebral angiography or spiral CT scan angiography of the head to reveal the location and size of the aneurysm
• Electroencephalogram (EEG) if seizures occur

Treatment

Symptoms often do not appear until bleeding (a rupture) occurs. A ruptured cerebral aneurysm is an emergency condition. The goal of treatment is to control symptoms and prevent further bleeding. Lowering blood pressure can reduce the risk.

Neurosurgery is the main treatment for cerebral aneurysm. The base of the aneurysm is closed off with clamps, sutures, or other materials that prevent blood flow through the aneurysm.

In many cases, an alternative to surgery can be done by placing special coils or stents into the aneurysm through the arteries, which causes a clot to form and prevents further bleeding. This approach is considered less invasive than brain surgery, and in the appropriate circumstances, it is regarded as the best form of treatment.

If surgery cannot be done because of the patient's overall condition or the aneurym's location or size, medical treatment is similar to treatment for subarachnoid hemorrhage. Treatment may involve:

• Complete bedrest and activity restrictions
• Drugs to prevent seizures
• Medicines to control headaches and blood pressure

Once the aneurysm is repaired, prevention of stroke due to blood vessel spasm may be necessary. This may include intravenous fluids, certain medications, and actually letting one's blood pressure run high.

Expectations (prognosis)

The outcome varies. Patients who are in deep comas after an aneurysm rupture generally do not do as well as those with less severe symptoms.

Ruptured cerebral aneurysms are often deadly. About 25% of people die within 1 day, and another 25% die within about 3 months. Of those who survive, more than half will have some sort of permanent disability.

Complications

• Increased fluid pressure inside the skull
• Loss of movement in one or more parts of the body
• Other neurological problems (such as vision changes, difficulty speaking, or cognitive decline)
• Permanent loss of sensation of any part of the face or body
• Seizures, epilepsy
• Stroke
• Subarachnoid hemorrhage

Calling your health care provider

Go to the emergency room or call the local emergency number (such as 911) if sudden or severe headache occurs, particularly if you also have nausea, vomiting, seizures, or any other neurological symptoms. Also call if you have a headache that is unusual for you, especially if it is severe or "the worst headache ever."

Prevention

There is no known way to prevent the formation of a cerebral aneurysm. If discovered in time, unruptured aneurysms can be treated before causing problems.

The decision to repair an unruptured cerebral aneurysm is based on the size and location of the aneurysm, and the patient's age and general health. It must be carefully considered given the risks both in operating and in watchful waiting.

Answer 2

Definition

An aneurysm is a weak area in the wall of a blood vesel that causes the blood vessel to bulge or balloon out. When an aneurysm occurs in a blood vessel of the brain, it is called a cerebral aneurysm.

Alternative Names

Aneurysm - cerebral; Cerebral aneurysm

Causes, incidence, and risk factors

Aneurysms in the brain occur when there is a weakened area in the wall of a blood vessel. An aneurysm may be present from birth (congenital) or it may develop later in life, such as after a blood vessel is injured.

There are many different types of aneurysms. A berry aneurysm can vary in size from a few millimeters to over a centimeter. Giant berry aneurysms can reach well over 2 centimeters. These are more common in adults. Multiple berry aneurysms are inherited more often than other types of aneurysms.

Other types of cerebral aneurysm involve widening of an entire blood vessel, or they may appear as a "ballooning out" of part of a blood vessel. Such aneurysms can occur in any blood vessel that supplies the brain. Atherosclerosis, trauma, and infection, which can injure the blood vessel wall, can cause cerebral aneurysms.

About 5% of the population has some type of aneurysm in the brain, but only a small number of these aneurysms cause symptoms or rupture. Risk factors include a family history of cerebral aneurysms, and certain medical problems such as polycystic kidney disease, coarctation of the aorta, and high blood pressure.

Symptoms

A person may have an aneurysm without having any symptoms. This kind of aneurysm may be found when an MRI or CT scan of the brain is done for another reason.

A cerebral aneurysm may begin to "leak" a small amount of blood. This may cause a severe headache that a patient may describe as "the worst headache of my life." Another phrase used to describe this is a sentinel headache. This means the headache could be a warning sign of a rupture days or weeks after the headache first happens.

Symptoms may also occur if the aneurysm pushes on nearby structures in the brain or breaks open (ruptures) and causes bleeding into the brain.

Symptoms depend on the location of the aneurysm, whether it breaks open, and what part of the brain it is pushing on, but may include:

• Double vision
• Loss of vision
• Headaches
• Eye pain
• Neck pain
• Stiff neck

A sudden, severe headache is one symptom of an aneurysm that has ruptured. Other symptoms of an aneurysm rupture may include:

• Confusion, lethargy, sleepiness, or stupor
• Eyelid drooping
• Headaches with nausea or vomiting
• Muscle weaknessor difficulty moving any part of the body
• Numbness or decreased sensationin any part of the body
• Seizures
• Speech impairment
• Stiff neck (occasionally)
• Vision changes (double vision, loss of vision)

NOTE: A ruptured aneurysm is a medical emergency. Seek immediate medical help.

Signs and tests

An eye exam may show evidence of increased pressure in the brain (raised intracranial pressure), including swelling of the optic nerve or bleeding into the retina of the eye. A brain and nervous system (neurological) exam may show abnormal eye movement, speech, strength, or sensation.

The following tests may be used to diagnose cerebral aneurysm and determine the cause of bleeding in the brain:

• Cerebral angiography or spiral CT scan angiography of the head to reveal the location and size of the aneurysm
• Cerebrospinal fluid exam (spinal tap)
• CT scan of the head
• Electroencephalogram(EEG)
• MRI of the head

Treatment

Two common methods are used to repair an aneurysm:

• Clipping is the most common way to repair an aneurysm. this is done during open brain surgery. See also: Brain surgery (craniotomy)
• Endovascular repair, most often using a "coil" or coiling, is a less invasive way to treat some aneurysms.

If an aneurysm in the brain ruptures, it is an emergency that needs medical treatment and often requires surgery. Endovascular repair is more often used when this happens.

Even if there are no symptoms, your doctor may order treatment to prevent a future, possibly fatal rupture.

Not all aneurysms need to be treated right away. Those that are very small (less than 3 mm) are less likely to break open.

Your doctor will help you decide whether it is safer to have surgery to block off the aneurysm before it can break open (rupture).

Someone may be too ill to have surgery, or it may be too dangerous to treat the aneurysm because of its location.

Treatment may involve:

• Complete bedrest and activity restrictions
• Drugs to prevent seizures
• Medicines to control headaches and blood pressure

Once the aneurysm is repaired, prevention of stroke from blood vessel spasm may be necessary. This may include intravenous fluids, certain medications, and letting the blood pressure get high.

Expectations (prognosis)

The outcome varies. Patients who are in deep comas after an aneurysm rupture generally do not do as well as those with less severe symptoms.

Ruptured cerebral aneurysms are often deadly. About 25% of people die within 1 day, and another 25% die within about 3 months. Of those who survive, about 25% will have some sort of permanent disability.

Complications

• Increased pressure inside the skull
• Loss of movement in one or more parts of the body
• Loss of sensation of any part of the face or body
• Seizures
• Stroke
• Subarachnoid hemorrhage

Calling your health care provider

Go to the emergency room or call the local emergency number (such as 911) if you have a sudden or severe headache, especially if you also have nausea, vomiting, seizures, or any other neurological symptoms.

Also call if you have a headache that is unusual for you, especially if it is severe or your worst headache ever.

Prevention

There is no known way to prevent the formation of a berry aneurysm. Treating high blood pressure may reduce the chance that an existing aneurysm will rupture. Controlling risk factors for atherosclerosis may reduce the likelihood of some types of aneurysms.

If unruptured aneurysms are discovered in time, they can be treated before causing problems.

The decision to repair an unruptured cerebral aneurysm is based on the size and location of the aneurysm, and the patient's age and general health. The risks involved in both operating and watchful waiting must be carefully considered.

References

Bederson JB, Connolly ES Jr, Batjer HH, Dacey RG, Dion JE, Diringer MN, Duldner JE Jr, Harbaugh RE, Patel AB, Rosenwasser RH: American Heart Association Guidelines for the management of aneurysmal subarachnoid hemorrhage: a statement for healthcare professionals from a special writing group of the Stroke Council, American Heart Association. Stroke. 2009;40:994-1025.

Meyers PM, Schumacher HC, Higashida RT, Barnwell SL, Creager MA, Gupta R, McDougall CG, Pandey DK, Sacks D, Wechsler JR: American Heart Association. Indications for the performance of intracranial endovascular neurointerventional procedures: a scientific statement from the American Heart Associatino Council on Cardiovascular Radiology and Intervention. Stroke Council, council on Cardiovascular Surgery and Anesthesia, Interdisciplinary Council on Peripheral Vascular Disease, and Interdisciplinary Council on Quality of Care and Outcomes Research. Circulation.2009;119:2235-2249.

Patterson JT, Hanbali F, Franklin RL, Nauta HJW. Neurosurgery. In: Townsend CM, Beauchamp RD, Evers BM, Mattox KL, eds. Sabiston Textbook of Surgery. 18th ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 72.

Reviewed By

Review Date: 09/28/2010

Daniel B. Hoch, PhD, MD, Assistant Professor of Neurology, Harvard Medical School, Department of Neurology, Massachusetts General Hospital; and David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.