MRI Automated T1 Signal Intensity Detection of Diffuse Brain Manganese Accumulation in Cirrhosis.

ABSTRACT

BACKGROUND AND PURPOSE: Cirrhosis is associated with diffuse brain manganese deposition, which results in increased signal intensity (SI) in the brain on T1-weighted images, most often visualized in the globus pallidus. The purpose of this study was to determine if automated image intensity measurements can detect SI differences in the basal ganglia and other regions reported to have manganese deposition in patients with cirrhosis compared with controls. METHODS: T1 FSPGR images were acquired on 28 patients with cirrhosis and 28 age-sex-matched controls. FreeSurfer T1 SI values were obtained for the globus pallidus, putamen, cerebral white matter, cerebral cortex, and brainstem. SI ratios were computed for globus pallidus normalized to white matter and brainstem. SI values and SI ratios were compared between groups using t-tests. RESULTS: Among people with cirrhosis, T1 SI was significantly increased in the globus pallidus, putamen, cerebral white matter, cerebral cortex, and brainstem (P< .001), and the globus pallidus to brainstem ratio was significantly increased (P< .001). No significant difference was seen for globus pallidus to cerebral white matter T1 SI ratio (P = .38). CONCLUSIONS: Automatic assessment of T1 SI allows for rapid, objective identification of widespread T1 shortening associated with manganese deposition in cirrhosis, consistent with the global deposition of neurotoxic manganese seen in pathology studies. This automated T1 assessment may have broader utility for other conditions beyond cirrhosis impacting T1 SI.