Lancet Study Reports Some Right Sided Strokes may go Undiagnosed

July 30th 2005

Lancet Study Reports Right Sided strokes may go undiagnosed

Know the warning signs of a Stroke

It may be harder to detect a stroke in the right side of the brain than the left because speech is not affected. German researchers, in the July 30^th Lancet, report that patients may not be admitted to the hospital promptly because of the difficulty detecting the symptoms. Prompt treatment improves the survival rate during the acute phase of a stroke. This means people that need thrombolytic or other therapies won't get it quickly.

Both left and right strokes will affect day-to-day living. A right sided stroke will affect perception skills and spatial skills. The person suffering the stroke may have problems making sense of what they see, hear and touch. They may also have trouble judging depth, size and distance.

Dr. Christian Foerch and his colleagues at the Johann Wolfgang Goethe University in Frankfurt Germany evaluated data for over 20,000 stoke victims between 1997 and 2002. Most of the recorded cases were left hemispheric events (11,300 left and 8,700 right). Dr. Foerch’s does not believe left sided strokes are more common, so why the discrepancy?

According to the research "The probable explanation for our findings is that symptoms... are more noticeable if language or dominant hand function is affected, both of which are located in the left hemisphere in most individuals," said the researchers.

Cerebrovascular events (strokes) may go unnoticed even by friends and relatives because the accompanying characteristic neurological deficits are less noticeable. It is hoped the study will make emergency personnel more aware of right sided stroke symptoms. About 750, 000 people have a stroke in the US each year and about 20% die making stroke the third leading cause of death. It is also a leading cause of disability.

"Our study suggests differences in medical attention and subsequent management between patients with right and left hemispheric stroke," the researchers wrote. "Difficulties in recognition of symptoms due to right hemispheric stroke pose specific challenges for the effort to further optimize stroke management, particularly in the critical early hours of stroke."

It is recommended that doctors rely on specialized stroke units staffed by physicians who are skilled at making a careful assessment. "A cursory history and examination and a negative CT scan in the emergency department do not suffice," Dr. Fink wrote in his editorial (reported by Med Page Today). "MRI, including diffusion-weighted imaging, is extremely valuable to assist diagnosis of cerebral ischemia, particularly when the clinical picture is uncertain. Up to half the patients with clinically 'transient' ischemic attack will have positive diffusion-weighted imaging. Foerch and colleagues' study is a challenge for us not to neglect those who might have presented with some neglect."