What Is It?

Most of the time, strokes damage brain tissue in the outer part of the brain, called the cortex, or sometimes the lobes or hemispheres of the brain. However, some strokes injure deeper structures underneath the cortex. A stroke in this area of the brain is called a lacunar stroke.

A lacunar stroke occurs when one of the arteries that provide blood to the brain's deep structures is blocked. These arteries are small, and are uniquely vulnerable. Unlike most arteries, which gradually taper to a smaller size, the arteries of a lacunar stroke branch directly off of a large, high-pressure, heavily muscled main artery. High blood pressure (hypertension) can lead to lacunar strokes because it causes a pounding pulse. High blood pressure can directly damage these arteries. It also can dislodge small clumps or clots that can block blood flow. A clot typically forms inside one of these small arteries after the artery has become damaged by atherosclerosis, a condition in which fatty deposits (plaques) build up along the walls of blood vessels.

Unlike strokes that damage the cortex, lacunar strokes are only rarely caused by a blood clot that forms elsewhere in the body, such as the neck or heart, and travels through the bloodstream to the brain. A clot traveling through the bloodstream is called an embolus. It is difficult for an embolus to make its way into the small arteries that can cause a lacunar stroke.

Many of the deep brain organs that can be injured by a lacunar stroke help to relay communication between the brainstem and the brain cortex, or help to coordinate complicated body movements. In a lacunar stroke, brain cells in a relatively small area (3 millimeters to 2 centimeters) are damaged or killed by lack of oxygen. These small areas of brain destruction are called lacunes. Lacunar strokes involve only small areas of the brain, but they cause significant disability.

Lacunar strokes account for about 20% of all strokes in the United States.

Symptoms

The symptoms of lacunar stroke vary depending on the part of the brain that is deprived of its blood supply. Different areas of the brain are responsible for different functions, such as sensation, movement, sight, speech, balance and coordination.

Symptoms can include:

• Weakness or paralysis of the face, arm, leg, foot or toes

• Sudden numbness

• Difficulty walking

• Difficulty speaking

• Clumsiness of a hand or arm

• Weakness or paralysis of eye muscles

• Other neurological symptoms

In a person with prolonged, untreated high blood pressure, many areas of brain destruction can form, causing additional symptoms, including emotional behavior and dementia.

The sudden appearance of one or more of these symptoms is a warning sign that a stroke may be in progress. Sometimes, the small clots that can cause a lacunar stroke interfere with blood flow only for a few minutes. If the clot dissolves before damage is done, then symptoms can begin to improve within minutes and may go away completely. When symptoms go away without treatment and full recovery occurs within 24 hours, the event is called a transient ischemic attack (TIA). Never decide to wait to determine if you are having stroke symptoms. Get to an emergency room as quickly as possible to get treatment.

Diagnosis

Your doctor will ask about your medical history (high blood pressure, heart disease, smoking, high cholesterol and diabetes). He or she will check your vital signs (temperature, pulse, respirations and blood pressure) and might order an electrocardiogram (EKG).

Lacunar strokes usually are identified by a computed tomography (CT) scan or magnetic resonance imaging (MRI) scan of your brain. An MRI technique known as diffusion weighted imaging is particularly sensitive for identifying very new lacunar strokes.

Expected Duration

If your symptoms continue without improvement during the time you are traveling to an emergency center, it is best to assume that your event is a full-blown stroke, not a TIA. If lacunar strokes are treated early, full recovery is possible. If medicines restore circulation to the brain quickly, symptoms of a lacunar stroke may go away within hours. If blood supply is interrupted for a longer time, brain injury may be more severe, and symptoms may last for many weeks or months, requiring physical rehabilitation. There may be permanent disability.

Prevention

You can help to prevent lacunar stroke by preventing or controlling the risk factors for stroke high blood pressure, smoking, heart disease and diabetes. If you have high blood pressure or heart disease, follow your doctor's recommendations for modifying your diet and taking your medication. Exercise regularly, eat plenty of fruits and vegetables, and avoid foods filled with saturated fats and cholesterol. If you smoke, quit. If you have diabetes, monitor your blood sugar level frequently, follow your diet, and take your insulin or oral diabetes medication as your doctor has prescribed.

If you have had a lacunar stroke, your doctor may recommend a daily aspirin or other blood-thinning medication, such as ticlopidine (Ticlid) or clopidogrel (Plavix). These medicines may reduce your risk, but their benefit has been more obvious for stroke types other than lacunar strokes. If you have never had a stroke of any kind, you might lower your risk for a first stroke if you take a daily aspirin. There is strong evidence that stroke risk is reduced for women over the age of 45 who take aspirin once every other day. This benefit has not been proven for men.

Treatment

If doctors are able to provide treatment within three hours after symptoms start, they probably will use with a clot-dissolving medication. Although the blood-thinning medication heparin often is used to treat strokes that affect large arteries, it does not appear to help people with lacunar strokes recover.

A person who has had a lacunar stroke usually is hospitalized so that he or she can be observed in case symptoms worsen. A person with a severe stroke may need help with self-care or feeding. In the hospital, an occupational therapist and a physical therapist can help the person to work around a new disability and to regain strength after brain injury. Commonly, hospitalization is followed by a period of residence at a rehabilitation center, where additional intensive therapy may be given. The goal of rehabilitation is to maximize recovery. To prevent future strokes, it is very important for you to control high blood pressure. It helps to take a daily aspirin or other blood-thinning medication (ticlopidine or clopidogrel).

When To Call A Professional

Call for emergency treatment immediately whenever the symptoms of lacunar stroke occur, even if these symptoms last only a few minutes. For best results, stroke treatment must occur within three hours of the start of symptoms.

Prognosis

People often begin to recover within hours or days of a lacunar stroke. Lacunar strokes have a better rate of recovery than other strokes that involve larger blood vessels. More than 90% of people with a lacunar stroke will recover substantially within the first three months following the stroke.

Additional Info

National Institute of Neurological Disorders and Stroke

P.O. Box 5801

Bethesda, MD 20824

Phone: (301) 496-5751

Toll-Free: (800) 352-9424

TTY: (301) 468-5981

http://www.ninds.nih.gov/

National Stroke Association

9707 E. Easter Lane

Englewood, CO 80112

Phone: (303) 649-9299

Toll-Free: 800-787-6537

Fax: (303) 649-1328

http://www.stroke.org/