0
We're unable to sign you in at this time. Please try again in a few minutes.
Retry
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
Retry
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......
JAMA Patient Page |

Stroke Imaging FREE

Ryszard M. Pluta, MD, PhD, Writer; Cassio Lynm, MA, Illustrator; Robert M. Golub, MD, Editor
JAMA. 2011;306(11):1277. doi:10.1001/jama.306.11.1277.
Text Size: A A A
Published online

A stroke is a sudden event that leads to change or loss of brain function. When a stroke is caused by decreased blood flow to the brain, it is an ischemic stroke. When the cause is bleeding into the brain, it is a hemorrhagic stroke. When the bleeding is on the surface of the brain, it is a subarachnoid hemorrhage. The September 21, 2011, issue of JAMA includes an article on depression and stroke.

TESTS TO DIAGNOSE STROKE

It is important to diagnose the specific type of stroke because each may require a different treatment. There are several tests that can be used to diagnose the type of stroke:

  • A computed tomography (CT) scan uses x-rays to produce a 2-dimensional or 3-dimensional picture of the brain. A noncontrast CT scan (without intravenous injection of fluid) is very fast (less than 1 minute) and can accurately detect blood, so it is used to look for hemorrhagic stroke or subarachnoid hemorrhage. A computed tomography angiography (CTA) scan uses intravenous contrast fluid to visualize the arteries in the brain; it can help diagnose ischemic stroke by determining its cause (such as a clot in an artery) and can provide guidance for thrombolytic treatment (dissolving a clot).

  • Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) use the response of water molecules to powerful magnets to produce a detailed picture of the brain and its arteries. Although equally good as CT at finding blood, MRI is more accurate in the diagnosis of acute ischemic stroke and its cause. MRI and MRA can assess brain damage and its reversibility as well as the risk of complications from the stroke. MRI can also provide guidance for thrombolytic treatment but is not suitable for persons with cardiac pacemakers or certain other metal or electronic devices implanted in their bodies.

  • Ultrasonography uses high-frequency sound waves above the hearing threshold. Carotid ultrasound examines the arteries in the neck that provide blood to the brain. It can show blood clots, atherosclerotic plaques (blockages), and other problems that can cause ischemic stroke. Transcranial Doppler measures the direction and speed of blood flow in arteries in the brain. It can be used to find the position of an embolus (a clot in the artery) or the narrowing of an artery. Both carotid ultrasound and transcranial Doppler are used to confirm the findings of CTA and MRA and measure the effects of thrombolytic treatment.

  • Digital cerebral angiography is the most accurate test for problems with brain arteries, such as aneurysms or clots, but it requires surgical insertion of a catheter (tube) into an artery in the leg. It plays a limited role in acute stroke because it is riskier, takes a longer time, and requires more equipment and professional staff than the other imaging tests. However, digital cerebral angiography allows for a direct intravascular (from inside the artery) removal of an embolus, widening the artery with a balloon, putting in a stent (tube to keep the artery open), or injecting thrombolytic drugs to dissolve a clot. Thus, some stroke centers are using digital cerebral angiography for carefully selected patients.

FOR MORE INFORMATION

INFORM YOURSELF

To find this and previous JAMA Patient Pages, go to the Patient Page link on JAMA 's Web site at www.jama.com. Many are available in English and Spanish.

Sources: National Institute of Neurological Disorders and Stroke at the National Institutes of Health, National Library of Medicine

The JAMA Patient Page is a public service of JAMA. The information and recommendations appearing on this page are appropriate in most instances, but they are not a substitute for medical diagnosis. For specific information concerning your personal medical condition, JAMA suggests that you consult your physician. This page may be photocopied noncommercially by physicians and other health care professionals to share with patients. To purchase bulk reprints, call 312/464-0776.

Topic: DIAGNOSTIC PROCEDURES

Tables

References

Letters

CME
Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.

Multimedia

Spanish Patient Pages
Supplemental Content

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Articles Related By Topic
Related Collections
PubMed Articles
JAMAevidence.com

Users' Guides to the Medical Literature
Stroke

Users' Guides to the Medical Literature
Mild Stroke