Mid-brain pathology of Wilson's disease: MRI analysis of three cases.

MRI scans were obtained from three patients with Wilson's disease, all of whom showed rigidity and dysarthria; two also showed tremor and dystonia. Two had been treated with D-penicillamine for seven and 14 years, respectively and their neurological abnormalities had improved, but the third patient had not been treated. T2-weighted MRI of the mid-brain in all three revealed the characteristic "face of the giant panda" sign, consisting of high signal intensity in the tegmentum except for red nucleus, preservation of signal intensity of the lateral portion of the pars reticulata of the substantia nigra and hypo-intensity of the superior colliculus. The clinical significance of these MRI abnormalities is discussed.