Brain scan could test children for autism

The technique, which assesses structural changes in the brain, has already been tested on adults and shown to have an accuracy of 90 per cent.

In as little as two years it could start to revolutionise the way psychiatrists diagnose the developmental disorder, which affects more than 500,000 people in the UK.

Not only is the method far quicker than conventional ways of identifying autism, but up to 20 times more cost effective.

At present, the disorder is chiefly diagnosed by observing behavioural traits using a battery of tests which are evaluated by clinicians, and cost as much as 2,000. The brain scans take a matter of minutes and cost between 100 and 200.

Although it is likely to be used as an extra diagnostic tool at first, in time the technique could replace observational assessments completely.

Autism spectrum disorder (ASD) is the name given to a range of conditions caused by abnormalities in brain development.

Sufferers are affected in different ways but share an inability to communicate, form social relationships, and empathise. They may demonstrate repetitive use of words or movements.

Children as young as six months can exhibit signs of autism, and the disorder is also known to run in families.

The new technique developed by scientists at the Institute of Psychiatry, King's College London, involves taking pictures of the brain with a magnetic resonance imaging (MRI) scanner. These are reconstructed into 3D images and analysed by a computer programmed to spot hallmarks of autism in the structure of different brain areas.

The results of testing the technique on 40 adults were published in the Journal of Neuroscience.