title: Subcompartmentalization of extracellular extravascular space (EES) into permeability and leaky space with local arterial input function (AIF) results in improved discrimination between high- and low-grade glioma using dynamic contrast-enhanced (DCE) MRI.
abstract: OBJECTIVE
  To modify the generalized tracer kinetic model (GTKM) by introducing an additional tissue uptake leakage compartment in extracellular extravascular space (LTKM). In addition, an implicit determination of voxel-wise local arterial input function (AIF) Cp (t) was performed to see whether these changes help in better discrimination between low- and high-grade glioma using dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI).
  
  
  METHODS
  The modified model (LTKM) was explored and fitted to the concentration-time curve C(t) of each voxel, in which the local AIF Cp (t) could be estimated by a time invariant convolution approximation based on a separately measured global AIF Ca (t). A comparative study of tracer kinetic analysis was performed on 184 glioma patients using DCE-MRI data on 1.5T and 3T MRI systems.
  
  
  RESULTS
  The LTKM analysis provided more accurate pharmacokinetic parameters as evidenced by their relative constancy with respect to the length of concentration-time curve used. In addition, LTKM with local AIF resulted in improved discrimination between low-grade and high-grade gliomas.
  
  
  CONCLUSIONS
  LTKM with local AIF provides more accurate estimation of physiological parameters and improves discrimination between low-grade and high-grade gliomas as compared with GTKM.
authors: Department of Mathematics & Statistics, Indian Institute of Technology Kanpur, India.
authors: Prativa
authors: P
authors: Sahoo
authors: Ram K S
authors: RK
authors: Rathore
authors: Rishi
authors: R
authors: Awasthi
authors: Bhaswati
authors: B
authors: Roy
authors: Sanjay
authors: S
authors: Verma
authors: Divya
authors: D
authors: Rathore
authors: Sanjay
authors: S
authors: Behari
authors: Mazhar
authors: M
authors: Husain
authors: Nuzhat
authors: N
authors: Husain
authors: Chandra M
authors: CM
authors: Pandey
authors: Sudipta
authors: S
authors: Mohakud
authors: Rakesh K
authors: RK
authors: Gupta
mesh_terms: D000328:Adult; D001932:Brain Neoplasms / Q000150:complications / Q000378:metabolism* / Q000473:pathology*; D002536:Cerebral Arteries / Q000378:metabolism / Q000473:pathology; D003198:Computer Simulation; D003287:Contrast Media; D005110:Extracellular Space / Q000378:metabolism; D005260:Female; D019786:Gadolinium DTPA / Q000493:pharmacokinetics*; D005910:Glioma / Q000150:complications / Q000378:metabolism* / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D015233:Models, Statistical; D060787:Neoplasm Grading; D010539:Permeability; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA
keywords: DCE-MRI; general tracer kinetic model; glioma; leaky tracer kinetic model; local AIF