Figure 1.
Dynamic contrast-enhanced MR images of the AAA vessel wall.
(A, B and C) T1weighted images from a dynamic serie at the level of the maximal diameter acquired respectively before contrast injection, 3 and 6.5 minutes after contrast injection. Vessel wall enhancement already occurs in (B) but is clearly visible in (C) (indicated by arrow heads). (D) Contrast-enhanced T1weighted anatomical image at the same level as in (A,B and C) with drawn inner (red circle) and outer (green circle) vessel wall ROI.
Table 1.
Pharmacokinetic models and parameters.
Figure 2.
General arterial input function derived from 8 individual contrast concentration-time courses acquired from high temporal resolution scans.
Figure 3.
Fitting curves of contrast concentration-time courses.
Example of the AAA vessel wall contrast concentration-time course (squares) from one representative patient with fit curves for the three pharmacokinetic models. The fit curves were similar for the Tofts and Extended Tofts model. Please note the absence of a first pass peak and contrast reflux in the contrast concentration-time courses.
Table 2.
Relative fit errors and Ktrans fit uncertainties for the three pharmacokinetic models.
Figure 4.
Scan-rescan reproducibility of Ktrans.
(A) T1weighted anatomical image showing AAA with maximal diameter of 5.0 cm. (B and C) DCE-MRI images with overlay of parametric Ktrans maps from the same patient obtained from scans performed one week apart. The Patlak model was used. The left lateral AAA vessel wall exhibits higher Ktrans on both examinations. Ktrans maps are color-coded from 0 to 0.12 min−1.
Table 3.
Scan-rescan reproducibility of Ktrans for the three pharmacokinetic models.
Figure 5.
Correlation between Ktrans and AAA maximal diameter.
There was a statistically significant positive correlation between Ktrans and maximal diameter based on the Patlak model (A) using voxel-wise fitting (Spearman ρ = 0.38). The correlations between Ktrans and maximal diameter based on the Tofts (B) and Extended Tofts (C) models using voxel-wise fitting were weak and not significant (ρ = 0.18 and ρ = 0.22, respectively).