On the Use of DSC-MRI for Measuring Vascular Permeability

Area of Science:

• Radiology
• Medical Imaging
• Neuro-oncology

Background:

• Contrast agent extravasation complicates Dynamic Susceptibility Contrast-enhanced Magnetic Resonance Imaging (DSC-MR imaging) in brain tumors.
• Leakage parameters (K2, K(a)) from correction methods offer insights into vessel permeability, but their biophysical interpretation and relation to K(trans) are unclear.

Purpose of the Study:

• To investigate the simultaneous assessment of vascular density and permeability in glioma patients.
• To explore the biophysical interpretation of K2 and K(a) and their relationship with K(trans) using multi-echo DSC-MR imaging.

Main Methods:

• Acquired multiecho DSC-MR imaging data in glioma patients.
• Simultaneously computed and compared single- and dual-echo derived measures of K2, K(a), and K(trans) voxelwise.
• Investigated T1/T2* leakage effects and echo time dependency.

Main Results:

• K2 and K(a) showed nonsignificant correlations with K(trans) but a significant inverse relationship with each other.
• K2 and K(a) estimates differed significantly between T1 and T2* effect voxels, unlike K(trans).
• Significant differences in extracellular-extravascular volume fraction (v(e)) were observed, with K2 and K(a) showing quadratic relationships with v(e).

Conclusions:

• Multi-echo DSC-MR imaging allows simultaneous K(trans) estimation of brain tumor vascular permeability.
• Caution is advised when assuming a similar relationship for K2 and K(a) parameters due to their distinct behavior and dependencies.