Athetotic and spastic cerebral palsy: anatomic characterization based on diffusion-tensor imaging

To evaluate the anatomy of deep gray and white matter structures in children with athetotic cerebral palsy (CP) and those with spastic CP by using diffusion-tensor (DT) imaging and to investigate whether these types of CP have unique anatomic correlates that can support their diagnosis and prognosis.

This study was approved by the institutional review board of each participating institution, and written informed consent was obtained from the parents of each patient. DT imaging was used to retrospectively evaluate 19 children with clinically diagnosed athetotic CP (mean age, 3.4 years ± 3.3 [standard deviation]), 26 children with spastic CP (mean age, 3.3 years ± 3.2), and 31 healthy control subjects (mean age, 3.2 years ± 3.0). Fractional anisotropy (FA) and mean diffusivity (MD) were measured with a region of interest (ROI) method. The ROIs were drawn on bilateral deep gray and white matter structures, including projection fibers, association fibers, and commissural fibers. Statistical analysis was performed by using the Kruskal-Wallis test with Bonferroni correction. P < .05 indicated a significant difference.

FA values in the athetotic CP group were significantly lower than those in the control and spastic CP groups for multiple structures, including deep gray and white matter (P < .05 and P = .0001, respectively); these differences were also associated with increasing MD (P < .05 and P < .001, respectively). On the other hand, in the spastic CP group, the significantly decreased FA values, compared with those of the normal group, were limited to several white matter structures (P < .05 and P = .0001).

In children with athetotic CP, the extent of change on DT images due to early brain damage tends to be more diffuse, including multiple brain structures, compared with the changes in children with spastic CP.