Gliomatosis cerebri is a rare form of primary tumour of the CNS infiltrating in a diffuse manner extensive portions of the brain by astrocytic and less rarely oligodendroglial elements in varying stages of differentiation while causing minimal destruction of the preexisting cytoarchitecture. The clinical signs are non-specific and usually comprise deterioration of cognitive functions, impaired behaviour, headache, epileptic seizures and hemiparesis. MR examination of the brain usually detects poorly defined fusing lesions mostly of the white matter, at least in two, more frequently in several lobes. On T2-weighted MR images these areas are hypersignal ones and in sequences T1 they are isointense or hypointense. Establishment of the diagnosis is in view of the rather uncharacteristic clinical picture based on a combination of the MR finding on the brain and histological examination of bioptic specimens. The authors demonstrate a patient with rapidly progressive dementia and left-sided hemi- paresis to the fatal end. Only autopsy revealed the diagnosis of gliomatosis cerebri.

        Key words: gliomatosis cerebri, dementia