fig 1.

Case 1.

A and B, Axial T2-weighted MR images at 2 months show the supratentorial white matter is markedly edematous and hyperintense, the U fibers are diffusely involved, the basal ganglia are spared, and the ventricular size is normal. Periencephalic CSF collections are still consistent with immaturity of CSF absorption at this age.

C and D, Axial T2-weighted MR images at 10 months show the supratentorial white matter is still abnormally hyperintense, but edema has resolved and a certain degree of white matter loss is becoming apparent, especially around the trigones of the lateral ventricles and in the parietal lobes. The basal ganglia are normal. An arachnoid cyst (asterisk) has developed adjacent to the right frontal lobe.

E and F, Axial T2-weighted MR images at 24 months show the white matter loss is now particularly severe in the paratrigonal areas, where the cortex nearly abuts on the ventricular surface, and in the parietal lobes; however, there is bulk loss throughout the whole supratentorial white matter. There is also delayed myelination, as shown by absent hypointensity in the anterior limbs of both internal capsules. The right frontal arachnoid cyst (asterisk) is essentially unchanged in size.