MRI of the index patient at the age of 54 years.

<p>A. Sagital T1 weighted MRI of the brain showing atrophy of the cerebellar midline, particularly the vermis superior. B&C. Axial T2 weighted MRI showing linear T2 hypointensities in the pons. C. Axial T2 weighted MRI showing prolongation of T2 signal in the dentate nuclei. D. Sagital T2 weighted MRI showing atrophy of the cord, straight dorsal spine and loss of the dorsal kyphosis.