title: The precision of DCE-MRI using the tissue homogeneity model with continuous formulation of the perfusion parameters.
abstract: The present trend in dynamic contrast-enhanced MRI is to increase the number of estimated perfusion parameters using complex pharmacokinetic models. However, less attention is given to the precision analysis of the parameter estimates. In this paper, the distributed capillary adiabatic tissue homogeneity pharmacokinetic model is extended by the bolus arrival time formulated as a free continuous parameter. With the continuous formulation of all perfusion parameters, it is possible to use standard gradient-based optimization algorithms in the approximation of the tissue concentration time sequences. This new six-parameter model is investigated by comparing Monte-Carlo simulations with theoretically derived covariance matrices. The covariance-matrix approach is extended from the usual analysis of the primary perfusion parameters of the pharmacokinetic model to the analysis of the perfusion parameters derived from the primary ones. The results indicate that the precision of the estimated perfusion parameters can be described by the covariance matrix for signal-to-noise ratio higher than~20dB. The application of the new analysis model on a real DCE-MRI data set is also presented.
authors.affiliation: Dept. of Biomedical Engineering, Brno Univ. of Technology, Brno, Czech Republic; Inst. of Information Theory and Automation of the Academy of Sciences of the Czech Republic, Prague, Czech Republic. Electronic address: bartos@utia.cas.cz.
authors.forename: Michal
authors.initials: M
authors.lastname: Bartoš
authors.affiliation: Inst. of Scientific Instruments of the Academy of Sciences of the Czech Republic, Brno, Czech Republic.
authors.forename: Radovan
authors.initials: R
authors.lastname: Jiřík
authors.affiliation: Dept. of Biomedical Engineering, Brno Univ. of Technology, Brno, Czech Republic.
authors.forename: Jiří
authors.initials: J
authors.lastname: Kratochvíla
authors.affiliation: Masaryk Memorial Cancer Institute, Dept. of Radiology, Brno, Czech Republic.
authors.forename: Michal
authors.initials: M
authors.lastname: Standara
authors.affiliation: Inst. of Scientific Instruments of the Academy of Sciences of the Czech Republic, Brno, Czech Republic.
authors.forename: Zenon
authors.initials: Z
authors.lastname: Starčuk
authors.affiliation: Dept. of Biomedicine, Univ. of Bergen, Bergen, Norway; Dept. of Radiology, Haukeland University Hospital, Bergen, Norway.
authors.forename: Torfinn
authors.initials: T
authors.lastname: Taxt
mesh_terms: D000465:Algorithms; D001783:Blood Flow Velocity; D003198:Computer Simulation; D003287:Contrast Media / Q000493:pharmacokinetics*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008955:Models, Cardiovascular; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000503:physiopathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media
keywords: Bolus arrival time; Dynamic contrast-enhanced MRI (DCE-MRI); Parameter estimation; Perfusion