Diffusion-Weighted MR Imaging in Neonatal Nonketotic Hyperglycinemia

Patient 1, a 15-day-old neonate who presented with encephalopathy.

Axial fast spin-echo T2-weighted images (140/3800/2[TE/TR/NEX]) of the midbrain (A) and pons (B) show hyperintense lesions in the dorsal midbrain and pons (arrows). Axial diffusion-weighted MR images (100/10000/1000 [TE/TR/b factor]) of the midbrain (C) and pons (D) taken at the same levels show hyperintense lesions of restricted diffusion. The lesions are more conspicuous than on T2-weighted images, and additional lesions of restricted diffusion are seen in the bilateral cerebral peduncles (C, arrowheads). Susceptibility artifact is noted in the right frontal region from an ECG lead. Apparent diffusion coefficient maps show corresponding reduced apparent diffusion coefficient in the midbrain (E) and pons (F). Axial diffusion-weighted MR image (G) and apparent diffusion coefficient map (H) show restricted diffusion in the posterior limbs of the internal capsules (arrows). Susceptibility artifact is noted in the right frontal region from an ECG lead. Region of interest measurements of the posterior limbs of the right and left internal capsule show reduction of apparent diffusion coefficients to 0.87 μm²/msec and 0.97 μm²/msec, respectively. No signal intensity abnormality is seen in the corresponding fast spin-echo T2-weighted image (I).