title: Comparison of MR signal intensities of cerebral perivascular (Virchow-Robin) and subarachnoid spaces.
abstract: OBJECTIVE
  The purpose of this work was to compare quantitatively the T2-weighted MR signal intensity values of the perivascular (Virchow-Robin) spaces and the cerebrospinal fluid (CSF).
  
  
  METHODS
  Coronal 3D T2-weighted turbo spin echo MR images of the brain were evaluated in 44 subjects without any significant cerebral pathology. MR signal intensity values of the perivascular spaces around the anterior commissure and the CSF in the ventricles and the subarachnoid space were measured.
  
  
  RESULTS
  A statistically significant difference between the mean MR signal intensity values of the perivascular spaces and the CSF both in the ventricles and in the subarachnoid space was found. The intensity values in the ventricles and in the subarachnoid space were not statistically significantly different.
  
  
  CONCLUSIONS
  The perivascular spaces have a different MR signal intensity than the CSF-containing structures within and around the brain. This finding is in keeping with the statement that the perivascular spaces represent entrapments of interstitial fluid and are not the invagination of CSF-filled subarachnoid sheaths.
authors.affiliation: Department of Radiology, SSK Ankara Hospital, 06600 Ankara, Turkey.
authors.forename: M Halil
authors.initials: MH
authors.lastname: Oztürk
authors.forename: Ustün
authors.initials: U
authors.lastname: Aydingöz
mesh_terms: D002540:Cerebral Cortex / Q000098:blood supply*; D002552:Cerebral Ventricles / Q000033:anatomy & histology*; D002555:Cerebrospinal Fluid / Q000000981:diagnostic imaging*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D011859:Radiography; D012016:Reference Values; D013346:Subarachnoid Space / Q000473:pathology*