Globoid Cell Leukodystrophy: Distinguishing Early-Onset from Late-Onset Disease Using a Brain MR Imaging Scoring Method

Patient 1: early-onset GLD.

A–D, Axial T2-weighted images (4000/100/2 [TR/TE/excitations]) at 4 months of age show increased signal intensity in the dentate nuclei (curved arrows in A, target lesions), in cerebellar white matter (arrowheads in A), the brain stem pyramidal tract (arrows in B), the pyramidal tract within the posterior limb of the internal capsule (arrows in C), and the pyramidal tract in the corona radiata (arrows in D), resulting in a GLD MR severity score of 5.

E–H, Axial T2-weighted images (3000/80/1) at 10 months of age show stable dentate nuclear involvement (curved arrows in E), progressive cerebellar white matter (arrowheads in E), and progressive pyramidal tract involvement (arrows in F, G, and H). The development of moderate global atrophy, as evidenced by a widened third ventricle width (8 mm), widened frontal horn ratio (41%), and widened subarachnoid spaces, results in an MR severity score of 7.

Patient 5: early-onset GLD.

A and B, Axial T2-weighted images (3000/80/1) show subtle increased signal intensity within the cerebellar white matter (straight arrows in A), dentate nuclei (curved arrows in A), and posterior limbs of the internal capsule (arrows in B). There is relatively normal signal intensity within the basal ganglia and thalami. These are the characteristic MR findings in early-onset GLD. Because of the coexistent involvement of the corona radiata pyramidal tract, the MR severity score was 4.

C, Axial noncontrast CT scan at 7 months of age (2 weeks after MR imaging in B) shows abnormal increased density within the basal ganglia and thalamic nuclei (arrowheads).

Patient 17: late-onset GLD.

A, Axial fluid-attenuated inversion recovery MR image (6500/105, 180/1) shows symmetric increased signal intensity within the pyramidal tract (arrows) and parietooccipital white matter (arrowheads).

B, Axial T2-weighted MR image (3400/90/1) shows increased signal intensity in the posterior body of the corpus callosum (curved arrows) as well as the pyramidal tract (straight arrows).

Patient 6: early-onset GLD.

A–C, Axial T2-weighted images (2800/80/1) at 7 months of age show increased signal intensity in the pyramidal tract (arrows in A–C). Pyramidal tract involvement in children with white matter that has not yet myelinated can be identified by higher than normal high signal intensity of immature white matter on T2-weighted images.