April 13 (HealthDay News) -- A specialized ultrasound scan is helping more children with sickle cell disease avoid strokes, but that good news is tempered by the limited access most children with the disease have to labs offering this screening, a new report notes.

People with sickle cell disease, an incurable disorder of the red blood cells, run an increased risk of stroke. About 10 percent of children with the disease have a stroke before turning 21.

Since 1998, six times as many children with sickle cell disease now receive transcranial Doppler ultrasound (TCD) screening -- a test which a study at the time found could identify those at high risk of a stroke. When identified, these children would then get blood transfusions, which cut their stroke odds by more than 90 percent. As a result, the annual stroke rate of children with the disease has been cut by more than half in the past decade.

However, the researchers, who followed 157 sickle cell patients in northern California, found that the farther away a child lived from a lab offering TCD screening, the less likely he or she was to have had one done.

The American Academy of Neurology, which published the latest study in its April 14 issue of Neurology, recommends TCD screening for these children starting at age 2.

"Stroke in children with sickle cell disease should be a largely preventable disease, however, not all children at risk are getting screened," Dr. Heather J. Fullerton, with the University of California, San Francisco, said in a news release issued by the academy. "Limited access to labs that perform TCD screening, even among kids with comprehensive health insurance, appears to be a barrier to helping these kids reduce their high risk of stroke. Increased availability of these screening labs may help prevent stroke in these high-risk children."

SOURCE: American Academy of Neurology, news release, April 13, 2009