Fast magnetic resonance fingerprinting for dynamic contrast-enhanced studies in mice

Abstract

Purpose: The goal of this study was to develop a fast MR fingerprinting (MRF) method for simultaneous T₁ and T₂ mapping in DCE-MRI studies in mice.

Methods: The MRF sequences based on balanced SSFP and fast imaging with steady-state precession were implemented and evaluated on a 7T preclinical scanner. The readout used a zeroth-moment-compensated variable-density spiral trajectory that fully sampled the entire k-space and the inner 10 × 10 k-space with 48 and 4 interleaves, respectively. In vitro and in vivo studies of mouse brain were performed to evaluate the accuracy of MRF measurements with both fully sampled and undersampled data. The application of MRF to dynamic T₁ and T₂ mapping in DCE-MRI studies were demonstrated in a mouse model of heterotopic glioblastoma using gadolinium-based and dysprosium-based contrast agents.

Results: The T₁ and T₂ measurements in phantom showed strong agreement between the MRF and the conventional methods. The MRF with spiral encoding allowed up to 8-fold undersampling without loss of measurement accuracy. This enabled simultaneous T₁ and T₂ mapping with 2-minute temporal resolution in DCE-MRI studies.

Conclusion: Magnetic resonance fingerprinting provides the opportunity for dynamic quantification of contrast agent distribution in preclinical tumor models on high-field MRI scanners.

Keywords: MR fingerprinting; dynamic contrast-enhanced MRI; dysprosium; gadolinium; mouse.