MR Imaging and proton MR spectroscopy of the brain in Behcet's disease

Cerebral MR imaging (MR) and proton-MR spectroscopy (H-MRS) data are lacking in neurologically asymptomatic patients with Behcet's disease (BD). Aim of the following work was to assess MR and H-MRS characteristics of brain involvement over time in patients with BD without clinical neurological involvement. Forty cerebral MR and 12 H-MRS examinations obtained over a one to nine year follow-up in 17 patients with (group A n=9) or without (group B n=8) neurological involvement were retrospectively reviewed. Four group-B patients had a normal first MR examination whereas all group-A and four group-B patients showed single (n=3) or multiple (n=10) subcortical white matter foci of signal change. Large midbrain, basal ganglia or subcortical white matter lesions were depicted in six group-A patients. Comparison between initial and last MR examinations revealed 28 new small-to-medium size lesions. Over the course of the study, lesion enhancement was seen in five patients all belonging to group A. NAA/Cr and Cho/Cr ratios of supraventricular white matter did not show significant differences between patients and healthy controls or between group-A and group-B patients. Clinically silent cerebral involvement in the form of small-to-medium size subcortical lesions may be present at MR examination in BD patients. Large brainstem and basal ganglia lesions associated with overt neurological symptoms are characteristic of the disease. H-MRS of cerebral normal-appearing white matter does not show any significant metabolic change in BD.