title: Measurement of choroid plexus perfusion using dynamic susceptibility MR imaging: capillary permeability and age-related changes.
abstract: BACKGROUND
  The cerebrospinal fluid (CSF) plays a major role in the physiology of the central nervous system. The continuous turnover of CSF is mainly attributed to the highly vascularized choroid plexus (CP) located in the cerebral ventricles which represent a complex interface between blood and CSF. We propose a method for evaluating CP functionality in vivo using perfusion MR imaging and establish the age-related changes of associated parameters.
  
  
  METHODS
  Fifteen patients with small intracranial tumors were retrospectively studied. MR Imaging was performed on a 3T MR Scanner. Gradient-echo echo planar images were acquired after bolus injection of gadolinium-based contrast agent (CA). The software developed used the combined T1- and T2-effects. The decomposition of the relaxivity signals enables the calculation of the CP capillary permeability (K2). The relative cerebral blood volume (rCBV), mean transit time (MTT), and signal slope decrease (SSD) were also calculated.
  
  
  RESULTS
  The mean permeability K2 of the extracted CP was 0.033+/-0.18 s(-1). K2 and SSD significantly decreased with subject's age whereas MTT significantly increased with subject's age. No significant correlation was found for age-related changes in rCBV and rCBF.
  
  
  CONCLUSIONS
  The decrease in CP permeability is in line with the age-related changes in CSF secretion observed in animals. The MTT increase indicates significant structural changes corroborated by microscopy studies in animals or humans. Overall, DSC MR-perfusion enables an in vivo evaluation of the hemodynamic state of CP. Clinical applications such as neurodegenerative diseases could be considered thanks to specific functional studies of CP.
authors.affiliation: Image Processing Department, University Hospital, CHU Nord Place Victor Pauchet, 80054, Amiens, France, bouzerar.roger@chu-amiens.fr.
authors.forename: Roger
authors.initials: R
authors.lastname: Bouzerar
authors.forename: Bader
authors.initials: B
authors.lastname: Chaarani
authors.forename: Catherine
authors.initials: C
authors.lastname: Gondry-Jouet
authors.forename: Jadwiga
authors.initials: J
authors.lastname: Zmudka
authors.forename: Olivier
authors.initials: O
authors.lastname: Balédent
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D001783:Blood Flow Velocity / Q000502:physiology*; D002199:Capillary Permeability / Q000502:physiology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D002831:Choroid Plexus / Q000502:physiology*; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult