Navigation Links
MRI Images May Pinpoint Time of Stroke
Date:11/2/2010

By Maureen Salamon
HealthDay Reporter

TUESDAY, Nov. 2 (HealthDay News) -- MRI images can serve as a "surrogate clock" to pinpoint stroke onset in patients whose symptoms began during sleep, increasing the number of patients eligible for highly effective clot-busting therapy, according to a new study.

Researchers found that MRI data could accurately determine if patients had experienced stroke symptoms within a three-hour period or less, which would allow the use of a clot-busting drug that works best if administered within that window of time. Tissue plasminogen activator, known as tPA, can dramatically reverse stroke symptoms in those whose strokes are caused by blood clots and blockages, which account for an estimated 85 percent of all strokes.

Strokes strike about 795,000 Americans each year, killing 137,000, according to the U.S. Centers for Disease Control and Prevention. The condition is a leading cause of serious, long-term disability in the United States.

"A tool that can estimate the age of stroke would be of great value in cases of unknown stroke onset time," said lead researcher Dr. Catherine Oppenheim, professor of radiology at Universite Paris Descartes in France. "This concerns as many as a quarter of all stroke patients who cannot be given tPA because they wake up with stroke symptoms or are unable to say when their stroke began."

Under current guidelines, patients who awaken with symptoms are arbitrarily excluded from tPA therapy, Oppenheim said, because the onset is considered to be the last time the patient was symptom-free, which might have been the night before.

The clot-busting drug is recommended for use only within 4.5 hours of stroke onset because it carries a risk of brain hemorrhage, a potentially fatal prospect, with the risk increasing as more time passes.

The study, reported online Nov. 2 and in the December issue of the journal Radiology, reinforces results from similar research, Oppenheim said. Her team reviewed MRI images from 130 patients treated for clot-caused strokes at Sainte-Anne Hospital in Paris between May 2006 and October 2008.

Of those patients, whose average age was 64.7 years, 63 underwent MRI within three hours of stroke onset and 67 were imaged between three and 12 hours afterwards. With the MRI data, radiologists could predict with more than 90 percent accuracy which patients had experienced stroke symptoms for longer than three hours.

However, the study did not compare patients with unknown stroke onset who received tPA to those who did not, Oppenheim said.

"Providing stroke neurologists with a reliable marker of stroke age will help to ensure that patients . . . are managed as urgently as those with known stroke onset time," she said. "These results will be useful for centers that offer 24-hour access to acute stroke patients. The main limitation is the limited access to MRI in emergency rooms worldwide."

Oppenheim said the next step would be clinical trials to validate whether MRIs serve as a "surrogate clock" for stroke onset.

Several doctors specializing in stroke care were encouraged by Oppenheim's study, though they cautioned further research would be necessary to determine if the results could be replicated.

"It's potentially helpful, and I don't know that it would take years to prove that," said Dr. Larry B. Goldstein, director of the Duke University Stroke Center in Durham, N.C.

Goldstein noted that about 40 percent of stroke patients who arrive at his facility within two hours of symptom onset receive tPA. If they don't, "the major reason . . . is that they get there too late," he said.

Dr. Wally Ghurabi, emergency department director at Santa Monica-UCLA Medical Center, said a group of ongoing studies there include a similar focus on MRIs and stroke.

"Really pinpointing the time of onset is so crucial for us. This will definitely give us that edge," Ghurabi said. "I've seen it with my own eyes -- a 60-year-old male or female patient comes into the ER and they're not able to move on one side or speak. A couple of hours later [after therapy], they can walk and talk. What more could we as doctors want?"

Dr. David F. Kallmes, an interventional neuro-radiologist at the Mayo Clinic in Rochester, Minn., was also optimistic about Oppenheim's results.

The MRI is "trying to act as a surrogate clock," said Kallmes, who edited Oppenheim's journal article. "Like any imaging technique, it has a certain accuracy but it won't be perfect. It's certainly an innovative approach for patients with stroke-like symptoms."

In October 2008, the American Heart Association, the American Stroke Association and the European Stroke Association revised their guidelines to recommend that tPA be used up to 4.5 hours after the onset of an ischemic (clot-caused) stroke, but the U.S. Food and Drug Administration has not yet revised its approved treatment window of 3 hours.

A study in The Lancet Neurology also found that a slight increase in deaths and bleeding in an extended treatment group over a three-month follow-up period underlined the notion that treatment within 3 hours -- although not required -- is still optimal.

More information

Review the warning signs of stroke at the American Stroke Association.

SOURCES: Catherine Oppenheim, M.D., Ph.D., professor of radiology at Universite Paris Descartes, France; Larry B. Goldstein, M.D., director, Duke University Stroke Center, Durham, N.C.; Wally Ghurabi, D.O., emergency department director, Santa Monica-UCLA Medical Center, Santa Monica, Calif.; David F. Kallmes, M.D., professor of radiology, Mayo Clinic, Rochester, Minn.; December 2010, Radiology


'/>"/>
Copyright©2010 ScoutNews,LLC.
All rights reserved  

Related medicine news :

1. Movies Loaded With Images of Junk Food
2. CT and MRI Images Now Seen in a 3D Virtual Reality World
3. Heart Aflutter? Remarkable New Images Show What it Looks Like in 4-D
4. Compton's by Britannica Revised for 2010; Hundreds of Articles Rewritten, Hundreds of New Photos, Images
5. Reflex Stock Limited Announces Two New Ways to Buy Stock Images and Stock Photos
6. Citizen Stock Launches Industry's First Rights Managed Database of Images Shot Exclusively Against White
7. NYUs Movshon receives Champalimaud Vision Award for work on how brain reconstructs images
8. Brainstem, spinal cord images hidden in Michelangelos Sistine Chapel fresco
9. Images shed new light on inflammation
10. Scientists Pinpoint Area of Brain That Fears Losing Money
11. Pinpointing immune system disturbances in celiac disease
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
MRI Images May Pinpoint Time of Stroke
(Date:2/17/2017)... ... February 17, 2017 , ... For the first time, International ... the exhibit floor for the 2017 HIMSS Conference & Exhibition at ... 2017, more than 40,000 healthcare industry professionals are expected at the conference, where ...
(Date:2/17/2017)... ... 17, 2017 , ... Qualis Health, one of the nation's ... Annual DecisionHealth Platinum Awards in recognition of its innovative healthcare management programs that ... multiple award categories, highlighting four of the organization’s current programs:, ...
(Date:2/17/2017)... Miami, F.L. (PRWEB) , ... February 17, 2017 ... ... geared to clinical operations executives and focusing on all facets of clinical trial ... portfolio management , patient engagement, and more. In addition, attendees stopping by ...
(Date:2/17/2017)... CO (PRWEB) , ... February 17, 2017 , ... Top ... annual International Healing NET Foundation Summit from February 21 - 23 in Beaver Creek, ... Foundation (HNF). This marks the Summit’s second year in Beaver Creek, hosting over 60 ...
(Date:2/16/2017)... ... 2017 , ... For some cancer survivors, the memories and ... researchers at The Marcus Institute of Integrative Health at Thomas Jefferson University ... symptoms of traumatic stress in cancer patients and published their results ...
Breaking Medicine News(10 mins):
(Date:2/17/2017)... 2017 Theravance Biopharma, Inc. (NASDAQ: ... today announced the presentation of positive clinical data ... pan-Janus kinase (JAK) inhibitor designed to be intestinally ... the European Crohn,s and Colitis Organization (ECCO). In ... from its completed Phase 1 study of single-ascending ...
(Date:2/17/2017)... 2017 Research and Markets has announced the addition ... to their offering. ... provides separate comprehensive analytics for the US, Canada , ... Asia-Pacific , Latin America , and Rest of ... 2022. Also, a six-year historic analysis is provided for these markets. Market ...
(Date:2/17/2017)... , Feb. 17, 2017   FormFast , ... announced a new partnership with Engage , one ... United States . FormFast will serve as the ... Engage,s implementations with MEDITECH .  ... essential functionality to complement and enhance the electronic health ...
Breaking Medicine Technology: