High-intensity basal ganglia lesions on T1-weighted images in two toddlers with elevated blood manganese with portosystemic shunts.

We report two toddlers with portosystemic shunts who had symmetrical high-signal globus pallidus lesions on T1- but not T2-weighted MRI, and measurement of whole blood manganese at 2 years of age. These cases suggest that portosystemic shunts can cause elevation of blood manganese and result in manganese accumulation in the globus pallidus, causing high signal on T1-weighted images even in asymptomatic toddlers.