One of the challenges of autism is diagnosing children early so that children can receive appropriate interventions as soon as possible. New research that makes use of MRI scans of infants has found a link between excess brain fluid and autism, providing a possible way for autism to be diagnosed at ages as young as six months.

Researchers examined infants (some whose siblings had autism as a way to increase the likelihood of finding children who would later be diagnosed) for excess brain fluid using MRI scans. The infants were trained to sleep while wearing giant earphones that would block out the MRI’s noise and then they were underwent an MRI. The initial scan of the 55 children took place at either six or nine months of age. The two subsequent scans took place at six month intervals.

After the scans were completed, the images were sent to a pediatric radiologist who created a system of quantifying the amount of cerebrospinal fluid present. They found that the children who were later diagnosed with autism had around 20% more fluid in the brain than those who were not. Of the 42 children who completed the study, 21 were later diagnosed with autism. Additionally, the children with autism had more brain fluid than children diagnosed with other disorders, which suggests that this issue is specific to autism. The amount of brain fluid and severity of symptoms showed a positive correlation.

This research may offer an explanation for why children with autism often have abnormally large heads or enlarged brains.

Although radiologists typically consider excess brain fluid to be benign, the possibility exists that it is part of the cause of autism. Cerebrospinal fluid is like the brain’s sewage system, flushing out waste products into the body’s circulation.

This research could lead to early detection of autism, which is important because earlier detection means earlier interventions. Lead investigator David Amaral, professor of neurobiology at the University of California Davis MIND Institute commented, “This could be very helpful to families to make the decision about whether they want to invest the time and financial resources to get their child into intensive behavioral therapy.”

This study is published in the journal The Brain.

To learn more about iLs and autism, visit our autism page.

Previous news in autism: