Abstract
Background Perivascular spaces (synonym: Virchow-Robin spaces) were first described over 150
years ago. They are defined as the fluid-filled spaces surrounding the small penetrating
cerebral vessels. They gained growing scientific interest especially with the postulation
of the so-called glymphatic system and their possible role in neurodegenerative and
neuroinflammatory diseases.
Methods PubMed was used for a systematic search with a focus on literature regarding MRI
imaging and evaluation methods of perivascular spaces. Studies on human in-vivo imaging
were included with a focus on studies involving healthy populations. No time frame
was set. The nomenclature in the literature is very heterogeneous with terms like
“large”, “dilated”, “enlarged” perivascular spaces whereas borders and definitions
often remain unclear. This work generally talks about perivascular spaces.
Results This review article discusses the morphologic MRI characteristics in different sequences.
With the continual improvement of image quality, more and tinier structures can be
depicted in detail. Visual analysis and semi or fully automated segmentation methods
are briefly discussed.
Conclusion If they are looked for, perivascular spaces are apparent in basically every cranial
MRI examination. Their physiologic or pathologic value is still under debate.
Key Points
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Perivascular spaces can be seen in basically every cranial MRI examination.
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Primarily T2-weighend sequences are used for visual analysis. Additional sequences
are helpful for distinction from their differential diagnoses.
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There are promising approaches for the semi or fully automated segmentation of perivascular
spaces with the possibility to collect more quantitative parameters.
Citation Format
Key words
perivascular spaces - glymphatic system - MR imaging