How do we diagnose a stroke?
Carotid Ultrasound is a simple test that can be used to assess the blood flow to the brain through the arteries in the neck called the carotid arteries. Sometimes these arteries become narrowed or occluded resulting in symptoms of a stroke.
Computed Tomography (CT)
CT or CT Angiography (CTA) scans are usually the first test to look for a stroke. CT is most useful to look for a hemorrhagic stroke as blood is typically well seen on a CT scan. Excluding a bleeding vessel means that any blocked vessel can be safely treated with medications to restore normal blood flow. A CTA uses contrast to very accurately show the blood vessels in the head and neck. This is the most accurate test to look for an occluded blood vessel.
Magnetic Resonance Imaging (MRI)
MRI or MR Angiography (MRA) is another important tool for diagnosing strokes. Just after a stroke occurs the CT scan of the brain is usually normal. An MRI however can easily show the early stroke which can help doctors know when to treat with medications that may restore normal blood flow. MRA is also a good test to look at the blood vessels in the head and neck.
Cerebral angiography is the best test to look for a common source of brain bleeding (aneurysm) and is used both in the process of treating an aneurysm or treating a focal blood clot in the brain. Angiography is usually performed by a specially trained neuroradiologist.