Uncertainty estimation in dynamic contrast-enhanced MRI

Anders Garpebring1, Patrik Brynolfsson, Jun Yu

  • 1Division of Radiation Physics, Department of Radiation Sciences, Umeå University, Umeå, Sweden. anders.garpebring@radfys.umu.se

Insights

This study introduces a new method for calculating uncertainty maps for pharmacokinetic parameters derived from dynamic contrast-enhanced MRI (DCE-MRI). The method accurately estimates uncertainties from common data errors, improving the reliability of DCE-MRI analysis in tumors.

Area of Science:

  • Medical Imaging
  • Biophysics
  • Radiology

Background:

  • Dynamic contrast-enhanced MRI (DCE-MRI) is used to estimate pharmacokinetic (PK) parameters reflecting physiological properties, particularly in tumors.
  • Errors in DCE-MRI data propagate non-trivially to PK parameters, complicating interpretation.
  • Quantifying these uncertainties is crucial for accurate clinical assessment.

Purpose of the Study:

  • To develop and evaluate a method for calculating uncertainty maps of PK parameters derived from DCE-MRI.
  • To assess the impact of various error sources on PK parameter uncertainty.
  • To validate the proposed method using simulations and in vivo data.

Main Methods:

  • A multivariate linear error propagation method was developed to calculate PK parameter uncertainty maps.
  • The modified Kety model was used to investigate PK parameter uncertainties.
  • Monte Carlo simulations and in vivo brain tumor data were employed for evaluation.

Main Results:

  • The proposed method accurately estimated PK parameter uncertainties arising from noise in dynamic data.
  • Uncertainties due to up to 15% signal/T1 map noise and arterial input function amplitude errors were well-estimated.
  • The method showed less accuracy for errors in bolus arrival time, with significant disagreements for K(trans), ve, and vp.

Conclusions:

  • The developed method offers an efficient way to calculate uncertainty maps for PK parameters in DCE-MRI.
  • The method is applicable to various sources of uncertainty, enhancing the robustness of DCE-MRI analysis.
  • Accurate uncertainty quantification is vital for reliable interpretation of DCE-MRI derived parameters in clinical settings.