title: Sampling requirements in DCE-MRI based analysis of high grade gliomas: simulations and clinical results.
abstract: OBJECTIVE
  To investigate the effect of variations in temporal resolution and total measurement times on the estimations of kinetic parameters derived from dynamic contrast-enhanced (DCE) MRI in patients with high-grade gliomas (HGGs).
  
  
  METHODS
  DCE-MRI with high temporal resolution (dynamic sampling time (T(s)) = 2.1 s and 3.4 s) and total sampling time (T(acq)) of 5.2 min was acquired in 101 examinations from 15 patients. Using the modified Tofts model K(trans), k(ep) v(e) and v(p) were estimated. The effects of increasing T(s) and reducing T(acq) on the estimated kinetic parameters were estimated through down-sampling and data truncation, and the results were compared with numerical simulations.
  
  
  RESULTS
  There was an overall dependence of all four kinetic parameters on T(s) and T(acq). Increasing T(s) resulted in under-estimation of K(trans) and over-estimation of V(p), whereas k(ep) and V(e) varied in a less predictable manner. Reducing T(acq) resulted in over-estimation of K(trans) and k(ep) and under-estimation of v(p) and v(e). Increasing T(s) and reducing T(acq) resulted in increased relative error for all four parameters.
  
  
  CONCLUSIONS
  Estimated K(trans), K(ep), and V(e) in HGGs were within 15% of the high sampling rate reference values for T(s) <20 s. Increasing T(s) and reducing T(acq) leads to reduced precision of the estimated values.
authors.affiliation: University of Oslo, Faculty of Medicine, Oslo, Norway. christopherlarsson88@gmail.com
authors.forename: Christopher
authors.initials: C
authors.lastname: Larsson
authors.forename: Magne
authors.initials: M
authors.lastname: Kleppestø
authors.forename: Inge
authors.initials: I
authors.lastname: Rasmussen
authors.forename: Raimo
authors.initials: R
authors.lastname: Salo
authors.forename: Jonas
authors.initials: J
authors.lastname: Vardal
authors.forename: Petter
authors.initials: P
authors.lastname: Brandal
authors.forename: Atle
authors.initials: A
authors.lastname: Bjørnerud
mesh_terms: D000328:Adult; D000368:Aged; D016477:Artifacts; D001812:Blood-Brain Barrier / Q000502:physiology; D001921:Brain / Q000098:blood supply / Q000473:pathology / Q000503:physiopathology; D001932:Brain Neoplasms / Q000098:blood supply* / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D002199:Capillary Permeability / Q000502:physiology; D003198:Computer Simulation; D003287:Contrast Media / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D005260:Female; D005500:Follow-Up Studies; D005583:Fourier Analysis; D005910:Glioma / Q000098:blood supply* / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007700:Kinetics; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009716:Numerical Analysis, Computer-Assisted; D009942:Organometallic Compounds / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C090600:gadobutrol