SIGNIFICANCE OF LEUKOARAIOSIS - CURRENT STATUS AND DIFFERENTIAL-DIAGNOSIS

Bilateral symmetric changes in the cerebral hemispheric white matter a re found with increasing frequency using CT and MRI techniques. These unspecific canges of the white matter signal are often called leukoara iosis. They differ from the normal white matter signal. These changes are found with increasing frequency in persons older than 60 years and also patients with dementia and cerebrovascular diseases. The pathoge nesis, clinical significance and morphological substrate are unclear. The aim of this review is to summarise the actual knowledge about the etiology and clinical signs and symptoms found in patients with leukoa raiosis. This term should not be used when white matter changes are fo und in patients younger than 35 years, with an unilateral onset,asymme tric distribution,and extensive changes all over the infra-and suprate ntorial white matter area. Neuroradiological and clinical criteria are given to differentiate between leukoaraiosis and diseases of the whit e matter, especially enlarged Virchow-Robin spaces, lacunar infarction , subcortical arteriosclerotic angiopathy (Binswanger's disease), leuk oencephalopathy of different origin,and demyelinating diseases.