"Our results suggest that multidetector CT could become the first-line imaging tool for identifying the cause of acute ischemic stroke," said the study's lead author, Loic Boussel, M.D., Ph.D., professor of radiology at Louis Pradel Hospital in Bron, France.
An ischemic stroke occurs when blockage in an artery, often from a blood clot or a fatty deposit due to atherosclerosis, interrupts blood flow to an area of the brain. This type of stroke can originate in the heart, in the form of a blood clot that travels to the head, or from blood vessels in the neck (extracranial carotid arteries) and head (intracranial arteries). According to the American Stroke Association, ischemic stroke accounts for approximately 87 percent of stroke cases.
Early determination of the cause of ischemic stroke is essential for secondary stroke prevention. Anticoagulant therapy to thin the blood is the treatment of choice for most of the cardiac sources of stroke, while surgery is needed for strokes caused by severe narrowing of the extracranial carotid artery.
Physicians use a combined imaging protocol to determine the cause of an ischemic stroke. The protocol typically includes duplex ultrasonography, MR angiography or CT angiography of the neck and brain vessels, and transthoracic and transesophageal echocardiography.
"This approach is time-consuming and expensive, and could delay secondary stroke prevention strategies," Dr. Boussel said.
In the new study, Dr. Boussel and colleagues analyzed the potential of multidetector CT as a faster and more cost-effective way to detect the main causes of ischemic stroke. The researchers compared a single-session multidetector CT examination of the heart, neck and brain vessels with established imaging methods in 46 patients who had recently experienced an ischemic stroke.
Almost half of the stroke cases had cardiac sources, while 20 percent of cases were caused by major arterial atherosclerosis.
Multidetector CT detected cardiac sources of stroke in 18 of 25 cases, for a sensitivity of 72 percent. The technique's sensitivity increased to 100 percent for detection of major arterial atherosclerosis. Overall, multidetector CT facilitated stroke classification in 38 of the 46 patients, or 83 percent.
"CT allows a fast diagnosis and helps to identify the cause of the stroke during a single examination," Dr. Boussel said. "Moreover, because it is quick, the exam is well tolerated, which is critical in acute stroke patients who may be unstable and agitated."
The CT protocol has two main limitations, according to Dr. Boussel. It exposes the patient to a significant radiation dose and requires two intravenous contrast material injections to study the chest and neck areas. Dr. Boussel said that advances in CT equipment technology could help reduce the radiation dose and the total amount of iodinated contrast material required.
Larger studies are needed to validate the results and to analyze the technique's cost-effectiveness.
"Ischemic Stroke: Etiologic Work-up with Multidetector CT of Heart and Extra- and Intracranial Arteries." Collaborating with Dr. Boussel were Serkan Cakmak, M.D., Max Wintermark, M.D., Ph.D., Norbert Nighoghossian, M.D., Ph.D., Romaric Loffroy, M.D., Philippe Coulon, Ph.D., Laurent Derex, M.D., Ph.D., Tae Hee Cho, M.D., and Philippe C. Douek, M.D., Ph.D.
Radiology is edited by Herbert Y. Kressel, M.D., Harvard Medical School, Boston, Mass., and owned and published by the Radiological Society of North America, Inc. (http://radiology.rsna.org/)
RSNA is an association of more than 46,000 radiologists, radiation oncologists, medical physicists and related scientists committed to excellence in patient care through education and research. The Society is based in Oak Brook, Ill. (RSNA.org)
For patient-friendly information on CT, visit RadiologyInfo.org.
A first look at interstitial fluid flow in the brain
05.07.2018 | American Institute of Physics
A sentinel to watch over ocular pressure
04.07.2018 | Fraunhofer Institute for Microelectronic Circuits and Systems
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
18.07.2018 | Life Sciences
18.07.2018 | Life Sciences
18.07.2018 | Information Technology