Leukodystrophies = DYSmyelinating diseases: Dysfunctional myelin formation or turnover. These are WM diseases as opposed to mitochrondrial dzs (Leigh Syndrome, MELAS) which are GM diseases.
- Metachromatic: Most common; frontal predominant. T2 bright deep WM changes that spares the venules = "Tigroid pattern." Spares subcortical U-fibers.
- X-Linked Adrenoleukodystrophy: Parietooccipital involvement of confluent T2 bright signal that spans the CC splenium. Can enhance and restrict.
- Canavan Dz: Confluent deep WM dz involving the subcortical U-fibers. Uniquely has high NAA.
- Krabbe: Small head. Changes to deep WM tracts, BG, posterior limb, thalamus. CT dense BG, with FLAIR bright areas above.