Keywords:
Liver, Oncology, MR physics, MR, Contrast agent-intravenous, Physics, Imaging sequences, Neoplasia
Authors:
M. Ippoliti, C. Kolbitsch, T. Schaeffter, A. Baur, M. R. Makowski; Berlin/DE
DOI:
10.26044/ecr2019/C-2048
Methods and materials
This preliminary study included 10 patients administered with Gadolinium-based contrast agents.
Data acquisition was carried out continuously for 5 min during contrast injection using 3D T1-weighted fat-suppressed Golden Radial Phase Encoding (GRPE) sampling scheme (Figure 1).
For each patient,
GRPE data were retrospectively split into different respiratory motion states and 3D non-rigid respiratory motion fields were obtained from the DCE data itself using a spline-based registration with normalized mutual information metric [3].
The motion information was utilized in the image reconstruction to yield 48 dynamic motion corrected volumes (Figure 2).
Improvement on image quality was assessed by measuring and comparing CNR values over a set of 19 hepatic lesions in motion corrected and non-corrected latest phase images (~228 s after contrast injection).
Statistical significance for the difference in average CNR values was ensured through paired sample t-test.
Finally,
quantitative contrast uptake information was obtained from the dynamic data using the Extended Toft’s model [4,5].