MRI of the brain and liver using T2 relaxation time measurements and proton spectroscopy (1H-MRS) of the brain was performed in four siblings with Wilson's disease (one with clinical disease and three asymptomatic) as well as age- and sex-matched control subjects. The T2 values of the liver were correlated with liver biopsy results. 1H-MRS of the left and right globus pallidus was obtained. The patient with clinical disease was examined three times, and two of three asymptomatic siblings twice. MR images of the brain were abnormal in all four patients. High signal intensity areas in the posterior thalamus, general atrophy and pontine myelinolysis were present in the patient with clinical manifestations. The T2 measurements of these areas confirmed the results of image analysis. Apart from general brain atrophy, the changes in the patient with clinical disease were largely reversible. The T2 values were significantly different from those of the control subjects only in the globus pallidus. The NAA/Cho, NAA/Cr and Cho/Cr ratios from the 1H-MR spectra of globus pallidus showed no significant difference between patients and control subjects. The mean values of NAA/Cho and NAA/Cr were lower in patients with Wilson's disease than in the control subjects. One of the patients had hepatic steatosis, but the liver T2 values were no different to those of the control subjects. In conclusion, the MRI findings reflect the success of the specific therapy in patients. MRI thus seems to be useful in the follow-up of Wilson's disease.