Fig. 5

Brain and spinal cord T2-weighted MRI representative of AARS2-related leukodystrophy. a MRI in (AARS2 patient) P1 at age 28. The sagittal T1-weighted image shows serious cerebellar atrophy and 2 strips of abnormal signal in the splenium (arrows in image 1). The axial T2-weighted images show inhomogeneous areas of abnormal signal in the periventricular white matter. The areas on the left and right are connected signal abnormalities in the corpus callosum (arrows in images 2–4). b MRI in (AARS2 patient) P2 at age 14 (images 1 and 2), age 21 (images 3 and 4), and age 23 (images 5–8). At age 14, a lesion is seen in the splenium of the corpus callosum (arrow in image 1) and in the right frontal periventricular white matter. The diffusion-weighted images suggest the presence of multiple small areas of restricted diffusion in the abnormal white matter (arrows in image 3), confirmed by low signal of the corresponding areas on the apparent diffusion coefficient map (arrows in image 4). The most recent MRI shows multiple segments of abnormal signal in the corpus callosum (image 5 and arrows in image 6). More extensive signal abnormalities are seen in the periventricular white matter, especially on the right (images 6 and 7). Signal abnormalities extend downward through the posterior limb of the internal capsule and the pyramidal tracts in the brainstem on the right (arrows in images 7 and 8). c MRI in (AARS2 patient) P3 at age 35. The midsagittal image shows that the anterior part of the corpus callosum is abnormal, whereas only a strip of signal abnormality is seen in the splenium (arrows in image 1). Images 2 and 3 illustrate that the frontal and parietal white matter is abnormal, whereas the central white matter in between is normal. The tract involvement is evident (arrows in images 2 and 4). The axial fluid-attenuated inversion recovery image shows that the affected white matter is rarefied (arrow in image 5). The axial T2-weighted images illustrate the involvement of the anterior limb of the internal capsule (image 6) and the frontopontine tracts going down into the brainstem (arrows in images 7 and 8). Reprinted with permission [10]