Patients typically present as newborns or young infants with failure to thrive, increased intracranial pressure and vomiting.
On imaging patients show increased T2 signal of the subcortical white matter, due to delayed myelination, resulting in blurring of the grey-white matter interface. Older patients will develop cerebral and cerebellar atrophy, with white matter loss and ex vacuo dilatation of the ventricular system. Patients (11/67) may also develop multifocal small T2 hyperintense white matter lesions
MRS may be normal, however some patients may have resonance peaks at 3.67 and 3.74 ppm. This peak can be differentiated from myo-inositol as it will invert with echo times between 135-144 ms. A large peak at 3.6 ppm on a short echo MRS supports a diagnosis of galactosemia.
References
Nelson MD et al, Radiology, 1992 Jul;184(1):255-261
Barkovich, Pediatric Neuroimaging