[Thalamic spectroscopy using magnetic resonance in autism].

OBJECTIVE

To evaluate the cerebral metabolic changes in paediatric patients using proton magnetic resonance spectroscopy.

PATIENTS AND METHODS

We studied 31 patients diagnosed as having autism (autistic group) using cerebral magnetic resonance and hydrogen spectroscopy, together with 15 patients without autism (control group). The groups were sub divided according to age: 0-3 years, 4-7 years and 8-13 years. The morphology of the brain was studied using magnetic resonance and hydrogen spectroscopy of the thalamus. In each case we evaluated the presence of morphological changes in the brain and the concentrations of the cerebral metabolites N acetyl aspartate(NAA), choline (Cho) and creatinine (Cr) by measuring the coefficients NAA/Cr, NAA/Cho and Cho/Cr coefficients, and also any anomalous concentrations of other metabolites.

RESULTS

No morphological changes were seen in the brains studied. There was no significant increase in minor metabolites in any of the groups studied. Significant differences in the NAA/Cho and NAA/Cr coefficients between the control and autistic groups were only seen in the oldest subgroup (8-13 years), but in the other groups the differences were not significant. The results in the sub group of older autistic children are similar to those of the younger subgroups in both autistic and control groups.

CONCLUSION

The spectroscopic findings showed similar recordings in the control group and in the autistic group up to the age of 7 years with reduced thalamic NAA in autistic patients older than this. This suggests interruption and regression in the process of neuronal maturity, in which the thalamus also plays a part.