Seven-Tesla Magnetic Resonance Imaging in Wilson Disease Using Quantitative Susceptibility Mapping for Measurement of Copper Accumulation

OBJECTIVES: In Wilson disease (WD), the copper content of cerebral tissue is increased, particularly in the basal ganglia. This study investigated whether a change in magnetic susceptibility can be detected using quantitative susceptibility mapping of the brain in patients with WD compared with healthy controls. MATERIALS AND METHODS: Eleven patients with WD (6 with the neurological form, 5 with the hepatic form) and 10 age-matched healthy controls who gave informed consent were examined at 7 T in a whole-body scanner (MAGNETOM; Siemens Medical Solutions, Erlangen, Germany) using a 24-channel phased array coil (Nova Medical). For imaging, a 3-dimensional spoiled gradient multiecho sequence (repetition time, 40 milliseconds; echo time, 9.76/19.19/28.62 milliseconds; bandwidth, 150 hertz per pixel; voxel size, 0.6 × 0.6 × 0.8 mm) was used. The susceptibility of selected regions (substantia nigra, red nucleus, pallidum, putamen, caudate nucleus) was analyzed in susceptibility maps. RESULTS: The patients with WD showed significantly increased susceptibility (P value, 0.001-0.05) in all analyzed regions compared with healthy controls. This was evident not only in patients with a neurological syndrome but also, with lower values, in patients with isolated hepatic manifestations. The distribution patterns of copper accumulation were different between the patients with neurological and non-neurological manifestations of the disease. CONCLUSIONS: In neurologically symptomatic and asymptomatic patients with WD, we found increased magnetic susceptibility in the brain tissue using quantitative susceptibility mapping.