MRI as potential diagnostic tool for autism

[Guest guest]

No major structural differences between the brains of people with autism and

those without it have been identified, with the exception of brain volume and

head circumference in children. So the bulk of neurological research on the

disorder focuses on how various regions of the brain communicate with one

another.

Now, in a study published in October in the journal Cerebral Cortex, researchers

at the University of Utah say they are one step closer to using magnetic

resonance imaging (MRI) to diagnose autism.

" This work adds an important piece of information to the autism puzzle, " says

principal investigator Janet Lainhart, an associate professor of psychiatry and

pediatrics. " It adds evidence of functional impairment in brain connectivity in

autism and brings us a step closer to a better understanding of this disorder.

When you understand it at a biological level, you can envision how the disorder

develops, what are the factors that cause it, and how can we change it. "

The researchers monitored 53 males with high-functioning autism and 39 typically

developing males from late childhood through early adulthood. MRIs of these

patients show lower-level communication between regions associated with

functions such as facial recognition and motor skills than the levels found in

MRIs of people without the disorder.

In the article abstract, the researchers note: " Interhemispheric connectivity

differences were better explained by diagnosis of autism than by potentially

confounding neuropsychological metrics of language, IQ, or handedness. "

While connectivity abnormalities have already been identified in patients with

autism in previous studies, this is the first of its kind to characterize

abnormalities in the entire brain rather than in specific pathways. Imaging of

the entire brain has the potential to help experts identify specific types of

the disorder.

" This is a complex disorder that doesn't just fall into one category, " Lainhart

says. " We hope the information can lead us to characterizing different types of

autism that may have different symptoms or prognoses that will allow us to

identify the best treatment for each affected individual. "

Because the study was limited to high-functioning males, the findings may not

translate to females, younger children, or " lower functioning " individuals with

autism, the researchers write. One skeptic, Bono of the autism advocacy

group " Safe Minds, " tells Business Week that using MRI as a primary screening

tool is unrealistic and therefore not terribly beneficial:

October 18, 2010 12:39 PM PDT

MRI as potential diagnostic tool for autism

Knowing that diagnosing autism is about looking for certain behaviors, only

children already identified as having issues that might be a function of autism

would be screened. So if there's no targeted treatment to follow up on the

results of this kind of scan, then it's just another expensive test for parents

who are already barraged with so many tests at diagnosis. And in that case, I

see this as just a waste of money.

So there's a bit of a Catch-22: the scans must be put to the test to develop

targeted treatments, but until there are targeted treatments, using the scans

widely is impractical and expensive.

Needless to say, this study is likely not the last to come from Lainhart's

autism imaging research group--which includes experts from the University of

Utah, Brigham Young University, the University of Wisconsin, and Harvard

University.