Direct Estimation of Pharmacokinetic Parameters from DCE-MRI using Deep CNN with Forward Physical Model Loss

TL;DR

This paper introduces a deep learning method that directly estimates pharmacokinetic parameters from undersampled DCE-MRI data by integrating a physical model into the loss function, improving accuracy and speed over traditional methods.

Contribution

A novel deep learning framework that incorporates a forward physical model into the loss function for direct PK parameter estimation from undersampled DCE-MRI data.

Findings

Accurate PK parameter reconstruction demonstrated on clinical brain DCE datasets.

Significantly faster inference compared to iterative reconstruction methods.

Improved fidelity of pharmacokinetic parameter estimation.

Abstract

Dynamic contrast-enhanced (DCE) MRI is an evolving imaging technique that provides a quantitative measure of pharmacokinetic (PK) parameters in body tissues, in which series of T1-weighted images are collected following the administration of a paramagnetic contrast agent. Unfortunately, in many applications, conventional clinical DCE-MRI suffers from low spatiotemporal resolution and insufficient volume coverage. In this paper, we propose a novel deep learning based approach to directly estimate the PK parameters from undersampled DCE-MRI data. Specifically, we design a custom loss function where we incorporate a forward physical model that relates the PK parameters to corrupted image-time series obtained due to subsampling in k-space. This allows the network to directly exploit the knowledge of true contrast agent kinetics in the training phase, and hence provide more accurate restoration of PK parameters. Experiments on clinical brain DCE datasets demonstrate the efficacy of our approach in terms of fidelity of PK parameter reconstruction and significantly faster parameter inference compared to a model-based iterative reconstruction method.