Behçet's disease is a chronic relapsing disorder of unknown etiology characterized by oral aphthous ulcerations, uveitis, genital ulcerations and bone lesions. A variety of other signs including polyarthritis, vascular conditions (blood vessel occlusions and aneurysms), epididymitis, gastrointestinal, pulmonary and heart lesions may also occur. Central nervous system (CNS) involvement is reported in 10-49% of cases and it is the first symptom of the disease in 5% of subjects. The neuro-Behçet's syndrome may appear as a brainstem syndrome, meningoencephalitis and an organic confusional syndrome or dementia. Cranial hypertension, mostly related to cerebral venous thrombosis, is also present in neuro-Behçet's disease and its incidence is reported in up to 10% of Behçet's patients. MRI is reportedly the most sensitive neuroradiologic approach to detect the focal lesions related to neuro-Behçet's disease and several single cases or series of Behçet's patients with neurologic signs have been examined with MRI. We used MRI to investigate CNS involvement in Behçet's disease patients with and without previous neurologic signs. MRI was carried out on 17 patients with ocular Behçet's disease without neurologic symptoms to assess the possible subclinical involvement of the CNS. Cerebrospinal fluid spaces were enlarged in 8 patients and 5 patients exhibited cortical atrophy. PD and T2-weighted hypersignal foci were demonstrated in parietal, frontal, subcortical and periventricular white matter in 6 subjects. Neuroradiologic abnormalities were found only in the patients with complete disease and with the disease diagnosed more than 10 years earlier. Even though the pathogenesis of these neuroradiologic abnormalities and their correlation with Behçet's disease remain to be clarified, our study suggests the possibility of subclinical CNS involvement in these patients, which may affect the therapeutic approach and their prognosis.