Regression of dilated perivascular spaces of the brain.

Purpose: Perivascular, or Virchow-Robin, spaces of the brain represent interstitial fluid-filled spaces continuous with subpial spaces, and not invagination of cerebrospinal fluid-filled subarachnoid spaces. Regression of a dilated, or even giant, perivascular space occurs rarely. The purpose of this paper is to describe magnetic resonance imaging evidence of complete regression of dilated perivascular spaces (dPVSs).