Bidirectional Contrast agent leakage correction of dynamic susceptibility contrast (DSC)‐MRI improves cerebral blood volume estimation and survival prediction in recurrent glioblastoma treated with bevacizumab

Abstract

Purpose To evaluate a leakage correction algorithm for T1 and T2* artifacts arising from contrast agent extravasation in dynamic susceptibility contrast magnetic resonance imaging (DSC‐MRI) that accounts for bidirectional contrast agent flux and compare relative cerebral blood volume (CBV) estimates and overall survival (OS) stratification from this model to those made with the unidirectional and uncorrected models in patients with recurrent glioblastoma (GBM). Materials and Methods We determined median rCBV within contrast‐enhancing tumor before and after bevacizumab treatment in patients (75 scans on 1.5T, 19 scans on 3.0T) with recurrent GBM without leakage correction and with application of the unidirectional and bidirectional leakage correction algorithms to determine whether rCBV stratifies OS. Results Decreased post‐bevacizumab rCBV from baseline using the bidirectional leakage correction algorithm significantly correlated with longer OS (Cox, P = 0.01), whereas rCBV change using the unidirectional model (P = 0.43) or the uncorrected rCBV values (P = 0.28) did not. Estimates of rCBV computed with the two leakage correction algorithms differed on average by 14.9%. Conclusion Accounting for T1 and T2* leakage contamination in DSC‐MRI using a two‐compartment, bidirectional rather than unidirectional exchange model might improve post‐bevacizumab survival stratification in patients with recurrent GBM. J. Magn. Reson. Imaging 2016;44:1229–1237.

Perfusion and diffusion MRI signatures in histologic and genetic subtypes of WHO grade II–III diffuse gliomas

“…A total of 12-25 slices were collected with matrix size ranging from 80 × 96 to 128 × 128. Relative cerebral blood volume (rCBV) was calculated using a recently introduced leakage correction algorithm using in-house custom MATLAB code that corrects for bidirectional contrast agent exchange [28,29] and normalizing to contra-lateral normal-appearing white matter (NAWM) tissue.…”

Effects of MRI Protocol Parameters, Preload Injection Dose, Fractionation Strategies, and Leakage Correction Algorithms on the Fidelity of Dynamic-Susceptibility Contrast MRI Estimates of Relative Cerebral Blood Volume in Gliomas

“…Simulated DSC-MR imaging signal curves for brain tumors were generated via the following: 1) selection of pulse sequence parameters; 2) construction of the DSC-MR imaging relaxivity-time-series without leakage for "ground truth rCBV"; 3) construction of the leakage-affected intravascular and EES contrast agent concentration-time-series based on tumor characteristics; and 4) estimation of CBV by using no leakage correction, unidirectional leakage correction (Unidir) as described by Boxerman et al, 10 or bidirectional leakage correction (Bidir) accounting for bidirectional contrast agent flux between the vasculature and EES. 11,13…”

“…4 To address these problems, strategies have been proposed for reducing the influence of contrast agent leakage, many focusing on T1weighted artifact reduction, including use of low flip angles, 5 dual-echo acquisitions, [6][7][8] preload administration, 9 and/or postprocessing leakage-correction algorithms. [10][11][12][13] Previous studies have used a combination of these strategies to reduce extravasation-induced error of CBV estimates; however, these approaches have primarily been evaluated empirically. The goal of this study was to systematically evaluate, with simulation, the effects of various leakage-correction strategies on the fidelity of CBV estimation using simulated DSC-MR imaging data derived from the convolution theory 14 and recent developments by Quarles et al 15 We hypothesized that this approach could provide insight into the interaction of pulse sequence parameters, preload dosing, and leakage-correction algorithms that are not readily determined experimentally.…”

Reliable estimation of microvascular flow patterns in patients with disrupted blood–brain barrier using dynamic susceptibility contrast MRI

“…We also note that the presented algorithm is not an attempt to provide a method specialized for CBV estimates, but rather to allow estimation of microvascular hemodynamic parameters in the potential presence of CA leakage, including CBV. For recent literature specifically targeted toward CBV, see Leu et al and Boxerman et al…”

“…We also note that the presented algorithm is not an attempt to provide a method specialized for CBV estimates, but rather to allow estimation of microvascular hemodynamic parameters in the potential presence of CA leakage, including CBV. For recent literature specifically targeted toward CBV, see Leu et al and Boxerman et al [25][26][27] The possible time delay between the site of measurement of the AIF, and the site of measurement of the tissue concentration curve is taken into account by allowing a shift of the AIF by an arbitrary delay d, as C a ðtÞ ! C a ðt2dÞ.…”