Reversibility of brain lesions in a case of Neuro-Behçet's disease studied by MR diffusion.

Behçet's disease is a multisystem disorder first described in 1937 as a triad of oral and genital ulcerations and uveitis. The etiology is unknown. Involvement of the central nervous system (CNS) occurs in 10-25% of patients. Neuro-Behçet's disease (NBD) can be classified as: (1) parenchymal, with a predilection for brainstem, basal ganglia and thalami involvement, subcortical white matter damage, spinal cord lesions, and meningoencephalitic presentations; (2) vascular, which usually affects major intracranial vessels with frequent involvement of the venous sinuses, cerebral veins and rarely intracranial arteries. Even if not constantly demonstrated in the CNS a vasculitic process involving small blood vessels, including venules, is regarded as an important pathological feature. We describe the case of a patient with NBD studied with conventional and diffusion weighted MR imaging.