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

PURPOSE: 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. MATERIALS AND METHODS: 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. RESULTS: 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). CONCLUSION: 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.

Quantitative diffusion tensor tractography of the motor and sensory tract in children with cerebral palsy.

AIM: the aim of this study was to compare the findings of quantitative diffusion tensor tractography of the motor and sensory tracts in children with cerebral palsy (CP) and typically developed comparison individuals, and also to evaluate the correlation with gross motor function. METHOD: thirty-four children with CP (mean age 2y 2.mo, SD 2y 0mo; 19 with spastic diplegia, eight with hemiplegia, six with spastic quadriplegia, and one with spastic triplegia) and 21 healthy comparison children (mean 2y 1.68mo, SD 2y 8.64mo) were evaluated. The distribution of Gross Motor Function Classification System (GMFCS) levels in the CP group was as follows: level I, 7; level II, 14; level III, 5; level IV, 3; and level V, 5. The following three diffusion tensor imaging (DTI) parameters including tractography were evaluated for each tract (corticospinal tract [CST] and posterior thalamic radiation [PTR]): number of fibres, tract-based fractional anisotropy, and region of interest (ROI)-based fractional anisotropy. We compared each value between the two groups, and correlated each value with the GMFCS level. RESULTS: the number of fibres and ROI-based fractional anisotropy values of both tracts were significantly lower in children with CP than in the comparison group (p<0.05-0.001). Additionally, there was significant negative correlation between GMFCS level and motor-sensory parameters (p<0.001-0.05). INTERPRETATION: DTI parameters of the CST and PTR in children with CP were significantly lower than in comparison children. In addition, these parameters were significantly correlated with GMFCS level.

Symmetrical central tegmental tract (CTT) hyperintense lesions on magnetic resonance imaging in children.

The central tegmental tract (CTT) is mainly the extrapyramidal tract connecting between the red nucleus and the inferior olivary nucleus. There are only a few case reports describing CTT abnormalities on magnetic resonance imaging (MRI) in children. Our purpose was to evaluate the frequency of CTT lesions and their characteristics on MRI, and to correlate the MR imaging findings with clinical features. We reviewed retrospectively the MR images of 392 children (215 boys and 177 girls) ranging in age from 1 to 6 years. To evaluate symmetrical CTT hyperintense lesions, we defined a CTT lesion as an area of bilateral symmetrical hyperintensity in the tegmentum pontis on both T2-weighted images and diffusion-weighted images in more than two slices. We measured the ADC (apparent diffusion coefficient) values of symmetrical CTT hyperintensity, and compared them with those of children without CTT abnormality. CTT lesions were detected in 20 (5.1%) of the 392 children. The mean ADC value for these 20 children was significantly lower than that of the normal CTT (p<0.001). On MR imaging, other than CTT lesions, associated parenchymal lesion included: none (n=6); other abnormalities, including periventricular leukomalacia (n=3); thin corpus callosum (n=3); ventricular dilatation (n=2); encephalopathy (n=2). Clinically, cerebral palsy was the most frequent clinical diagnosis (n=6), accounting for 30%, which was significantly more frequent than the prevalence of cerebral palsy among children without CTT lesions (13%) (n<0.05). CTT lesions were detected in 5.1% of all the children examined. Cerebral palsy was the most frequent clinical diagnosis.