Changes in Cerebral Gray and White Matter in Patients with Pantothenate Kinase-Associated Neurodegeneration: A Long-Term Magnetic Resonance Imaging Follow-Up Study

OBJECTIVE: To determine the volume changes in gray and white matter during a long-term follow-up in patients suffering from pantothenate kinase-associated neurodegeneration (PKAN). METHODS: Magnetic resonance imaging was repeated in 13 patients and 14 age-matched controls after a mean interval of more than 7 years. T1-weighted sequences were evaluated by fully automated atlas-based volumetry, compared between groups and correlated with disease progression. RESULTS: The patients did not show generalized cerebral atrophy but did show a significantly faster volume reduction in the globus pallidus during follow-up (between -0.96% and -1.02% per year, p < 0.05 adjusted for false discovery rate) than controls, which was significantly related to the progression in their dystonia scores (p = 0.032). CONCLUSION: The volume loss in the globus pallidus over time—together with the accumulation of iron known as the “tiger’s eye”—supports the pathophysiologic concept of this nucleus as a center of inhibition and its severe malfunction in PKAN.