Fig. 1

Brain MRI. a-c: SLC35A2-CDG patient at 22 months. d-f: Normal age and sex matched patient for comparison. a, d T1-weighted axial images, b, e TurboFLAIR axial images, c, f T2-weighted coronal images. Images a and b demonstrate mild widening of the cerebral sulci that is most notable in the frontal and temporal lobes. Shortening of the head in the anterior-posterior dimension (brachycephaly) was noted, which may be incidental as there are no other findings to suggest craniosynostosis. Image c also demonstrates cerebral volume loss. Delayed myelination is also best seen on c, exhibiting the lack of T2 hypointensity diffusely in the cerebral white matter (compared to f) expected for age. The delayed myelination is also evident on the TurboFLAIR image b as the lack of characteristic hypointensity in the posterior limbs of the internal capsules (long arrows) and in the deep white matter of the frontal lobes (short arrows)