MRI Study of Cerebral Blood Flow in Development Disorders in Children

The purpose of this study is reproduce the individual detection results by PET with Arterial Spin Labeling (ASL) MRI, to establish a biomarker useful in autism diagnosis.

Anatomical and functional abnormalities have been identified in the superior temporal sulcus (STS) in autism by brain imaging modalities, including positron emission tomography (PET), functional MRI and diffusion MRI. These results suggest that brain imaging abnormalities within the STS could be the first step in the cascade of neuronal abnormalities found in autism.

STS is known as a key area for social cognition and is involved in various stages of social interaction, from visual and auditory perception (perception of eyes, facial and body movements, and perception of human voice) to the more complex process of social cognition (theory of mind, understanding emotions and mentalizing) The anatomical and functional abnormalities within the STS described in autism could account for the social difficulties experienced by persons with autism, both clinically observed and objectified by studies on visual social perception.

The individual detection results found in PET, that is to say a reduction of rCBF in the superior temporal sulcus (STS), could be reproduced with ASL and used to predict the diagnosis of autism in children with the same level of sensitivity and specificity as with PET. The individual detection of decreased rCBF in the STS could be a useful biomarker in autism using MRI, a method more accessible and much less invasive than PET. A MRI biomarker in autism could allow individual analysis, as well as contribute to early diagnosis and objective evaluation of the efficacy of new therapeutic strategies.

The rCBF data measured by MRI-ASL will also be correlated with both clinical (Autism Diagnostic Interview - ADI-R) and behavioral data of the social perception measured by the eye-tracking method. In addition, we will study the impact of these temporal anomalies on brain connectivity MRI method of diffusion tensor. We will also describe the abnormalities present in the very early development of autism.

Eligibility Criteria:
Inclusion Criteria:

Patient diagnosed autist or suspected autist : males and females with the diagnosis of autism based on the following criteria:

* 5 years ≤ age \< 18 years,
* demand for MRI in the etiologic assessment (suspected autism) or MRI control in the treatment (diagnosed with autism)
* obtaining written consent from parents or legal guardians of patients.

Patients diagnosed with mental retardation or suspected with mental retardation : males and females with the diagnosis of mental retardation using the following criteria:

* 5 years ≤ age \< 18 years,
* demand for MRI in the etiologic assessment (suspected mental retardation) or MRI control in the treatment (diagnosed with mental retardation)
* obtaining written consent from parents or legal guardians of patients.

Healthy control subjects: males and females:

* 5 years ≤ age \< 18 years
* no known neurological or psychiatric disorder obtaining written consent with parents or legal guardians of volunteers.

Very young patients suspected of autism: male and female with suspected autism

1. 18 months ≤ age \<5 years
2. demand of MRI in the etiologic assessment
3. obtaining written consent from parents or legal guardians.

Very young patients suspected of mental retardation : male and female with suspected mental retardation

1. 18 months ≤ age \<5 years
2. demand of MRI in the etiologic assessment
3. obtaining written consent from parents or legal guardians.

All subjects must be registered with the social security.

Exclusion Criteria:

For all subjects:

* Indication against performing MRI (pacemaker, an implanted metal foreign body, claustrophobia),
* Inability of healthy volunteers to remain still during the MRI examination.

Healthy control subjects: males and females:

* aged between 5 years and 18 years
* no known neurological or psychiatric disorder
* obtaining written consent with parents or legal guardians of volunteers.

All subjects must be registered with the social security.

Exclusion Criteria:

For all subjects:

* Indication against performing MRI (pacemaker, an implanted metal foreign body, claustrophobia),
* Inability of healthy volunteers to remain still during the MRI examination.