Doctors diagnosed autism in children by using MRI to track brain circuit activity, according to research that suggests the method may help speed up detection and add to knowledge of the disorder’s biological base.
In a study of 60 children, half with mild autism and half with no autism, researchers identified the condition 94 percent of the time using magnetic resonance imaging, according to a study online this week in the journal Autism Research. The scans helped show how information moves and is processed in the brain.
About one in 110 children in the U.S. have an autism spectrum disorder, a developmental disability that can impair behavior, communication and social interaction, according to the U.S. Centers of Disease Control and Prevention. By using MRI, doctors were able to see thought activity by following the path of electrical impulses in the brain.
“We, for the first time, are able to begin to really see what is going on in the brain in children who have autism,” said Janet Lainhart, an associate professor at the University of Utah, in a Nov. 23 telephone interview. “That is usually the beginning of major advances in recognition, treatment and prevention. This type of research basically brings autism into modern medicine. Much more work needs to be done, but that’s exactly where it needs to go.”
Today’s findings build on earlier research of brain imaging to determine autism and may lead to a way to help doctors identify the disorder earlier, the researchers said. Current methods rely on interviews and observations.
The researchers from Harvard University, the University of Utah, Brigham Young University and the University of Wisconsin used a MRI test on 30 males ages 8 to 26 years old who had high functioning, or mild autism and also on 30 males who didn’t have autism.
The MRI looked at water diffusion along the axons -- the nerve fibers that transmit signals in the brain -- to see how information was being processed, said Nicholas Lange, the study’s lead author and an associate professor of psychiatry at Harvard University, in a Nov. 23 telephone interview. The researchers looked at areas of the brain responsible for language, social functioning and emotional behavior.
In those who had autism, the signals moved in many directions rather than in a single path, Lange said. That pattern meant it took longer for someone with autism to process certain information, he said.
The researchers said they replicated their results in a second, smaller set of patients.
“These results are not ready for clinical use,” Lange said. “They are the best thus far in terms of finding an important biological basis for the disorder but we don’t want to raise anyone’s false hope at the moment that they can walk into a clinic and ask that this test be done.”
James Mulick, a professor in the Department of Pediatrics and Psychology at Nationwide Children’s Hospital in Columbus, Ohio, who has studied autism for 35 years, said today’s findings add to research using brain imaging to diagnose the disorder. Mulick wasn’t an author on the paper.
“Here they’ve nailed down, in a population some might have difficulty classifying autism without these measures, significant structural differences in the brain,” he said in a Nov. 26 telephone interview. “In order to meet the behavior criteria for autism, you have to behave differently and the brain reflects the behavior.”
Using the scan to identify who has autism may also allow researchers to go back and study patients to help find possible genes that may have increased their vulnerability to the disorder, he said.
U.K. scientists showed in a study published in August in the Journal of Neuroscience that using MRI detected more than 90 percent of autistic patients who were previously diagnosed using intelligence tests, psychiatric interviews, physical examinations and blood tests.
Lange said his study focused on specific areas of the brain, while the U.K. study looked at the entire brain. The study published today analyzed brain tissue that transmits information while the previous report looked at tissue that helps patients perform functions, he said.
Marguerite Colston, vice president of constituent relations for the Bethesda, Maryland-based Autism Society, an advocacy group that raises awareness about the disorder, said the organization hopes studies like this will ultimately lead to earlier diagnosis of autism for all children. Currently, the average age of autism diagnosis in the U.S. is 4 years old. The group is striving to cut the age of diagnosis in half, she said.
Researchers plan to further study and develop the test. Additional studies are also needed to see if the test will work in those who are younger and in those whose autism symptoms are more severe, the researchers said.
“By refining this method in older individuals and really knowing what to look for, another important step will be developing it further so it can detect autism in children before critical symptoms are manifested,” Lainhart said.