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More about Transient Ischemic Attack:
Definition Causes and symptoms Diagnosis Treatment Prognosis Prevention Resources |
The goal of diagnosis is to identify the precise cause of the TIA and to recommend treatment. Initial information that an individual can supply includes a medical history, what drugs are currently being taken and why, and a full description of the symptoms. Blood tests are ordered to screen blood counts—that is, the numbers of specific blood cell types—and to measure sugar and lipid (fats, including cholesterol) levels. Based on this information and a physical examination that includes blood pressure, pulse, and respiration measurements, one or more of the following imaging tests are ordered.
A computed tomography scan (CT scan) or a magnetic resonance imaging (MRI) scan is usually the first imaging test. CT or MRI can rule out other problems, such as a tumor or subdural hematoma, which can mimic the symptoms of a TIA. A CT scan can also uncover aneurysms and arteriovenous malformation, both of which are blood vessel abnormalities that can cause bleeding in the brain.
Another imaging test that is very useful is carotid ultrasonography, a noninvasive procedure that allows examination of the interior of the carotid artery. This examination can detect carotid stenosis, a condition in which the artery is abnormally narrow because of atherosclerosis. Ultrasonography is very reliable in identifying stenosis, but it does not give enough information to accurately assess the degree of stenosis. Because the treatment used depends on the degree of stenosis, treatment decisions cannot be based on ultrasonography. Another type of ultrasonography, called transcranial doppler ultrasonography, is used to detect stenosis of the blood vessels within the brain and in the vertebrobasilar arteries.
If stenosis is identified, a further test called cerebral arteriography may be done. This test is not done if the individual is in poor health, because it may be too risky. Arteriography involves injecting a special dye into the blood vessels which makes them visible on x rays. This procedure is also used to find suspected problems with blood vessels in the brain. Because it is an invasive procedure, complications may arise. Typically, these complications are minor and temporary. In a very small percentage of people with cardiovascular disease, the procedure may cause serious complications, such as stroke.
Although TIAs affect the brain, the ultimate cause of the problem may be found in the heart. Heart disease or damage to the heart's blood vessels is assessed by echocardiography. Echocardiography is a type of ultra-sonography and is a noninvasive procedure.
— Julia Barrett
