When dilated, Virchow-Robin spaces (VRS) are often seen as intra-parenchymal foci of CSF signal on MRI or CT. Such foci are found in patients with miscellaneous clinical presentations so a determination of their radiological significance and clinical associations is needed.

This paper reports 5 patients and reviews the literature on VRS. The mechanisms of dilatation of VRS are still not well understood. They are found in two chief locations: in the high convexity white matter of healthy elderly people, or surrounding the lenticulo-striate vessels as they enter the basal ganglia. On MR images they can be misdiagnosed as lacunar infarcts. Most patients are asymptomatic. The small dilatations in the high convexity actually represent a normal anatomic variant, also called « état criblé ». Sometimes, giant dilatations corresponding to Poirier’s type IIIb « expanding lacunae » (Poirier, J., Presse Médicale, 1983; 12: 768; Poirier J and Derouesné C, Clin Neuropathol, 1984; 3: 266) are found in the basal ganglia and midbrain resulting in hydrocephalus. No other features e.g., miscellaneous symptoms such as headache and epilepsy reliably correlate with enlarged VRS seen on MR images.

Only patients in whom symptoms can be confidently ascribed to dilated VRS need appropriate treatment. Most patients remain asymptomatic.

57 references.