[Development of the brainstem and cerebellum in autistic children].

Studies of magnetic resonance images have revealed morphological disorders of the brainstem and cerebellum in autistic children and adults. When we studied development of the brainstem and cerebellum in autistic patients, these structures were significantly smaller in autistic patients than in controls. Although the brainstem and cerebellum significantly increased in size with age in both groups, the development of the pons, cerebellar vermis I-V and cerebellar vermis VI-VII was significantly more rapid in autistic patients than in controls. However, the development of the other brain structures in the posterior fossa did not differ between autistic patients and controls. The regression intercepts of the brainstem and cerebellum as well as those of their components were significantly smaller in autistic patients than in controls. These results suggested that significant anatomical changes took place in the posterior fossa brain structures in the prenatal period in autistic children, but were not progressive.