Unilateral subcortical extensive dilated perivascular spaces associated with superior sagittal sinus perivenous dilated spaces.

We present the MRI of a 70-year-old patient showing unilateral subcortical extensive dilated perivascular spaces with surrounding fluid-attenuated inversion recovery hyperintensities associated with the presence of small cysts and tubular hypointensities in and near the superior sagittal sinus co-locating with draining cortical veins on gadolinium-enhanced T1-weighted imaging representing probably (dilated) spaces between pial sheath and cortical vein walls. These (peri)venous superior sagittal sinus cysts seem to represent either hydrops cause (by blocking interstitial fluid flow in perivenous subpial space, via meningeal lymphatics) or consequence (where cysts might have been formed due to subpial fluid flow obstruction by unknown cause).