The Consistence of Dynamic Contrast‐Enhanced MRI and Filter‐Exchange Imaging in Measuring Water Exchange Across the Blood–Brain Barrier in High‐Grade Glioma

Background Water exchange across blood–brain barrier (BBB) (WEX BBB ) is an emerging biomarker of BBB dysfunction with potential applications in many brain diseases. Several MRI methods have been proposed to measure WEX BBB , but evidence remains scarce whether different methods can produce comparable WEX BBB . Purpose To explore whether dynamic contrast‐enhanced (DCE)‐MRI and vascular water exchange imaging (VEXI) could produce comparable WEX BBB in high‐grade glioma (HGG) patients. Study Type Prospective cross‐sectional. Subjects 13 HGG patients (58.4 ± 9.4 years, 9 females, 4 WHO III and 9 WHO IV). Field Strength/Sequence A 3 T, spoiled gradient‐recalled‐echo DCE‐MRI and VEXI containing two pulsed‐gradient spin‐echo blocks separated by a mixing block. Assessments The enhanced tumor and contralateral normal‐appearing white matter (cNAWM) volume‐of‐interests (VOIs) were drew by two neuroradiologists. And whole‐brain NAWM and normal‐appearing gray matter (NAGM) without tumor‐affected regions were segmented by automated segmentation algorithm in FSL. Statistical Tests Student's t ‐test was used to evaluate parameters difference between cNAWM and tumor, NAGM and NAWM, respectively. The correlation between vascular water efflux rate constant ( k bo ) from DCE‐MRI and apparent exchange rate across BBB (AXR BBB ) from VEXI was evaluated by Pearson correlation. P < 0.05 was considered statistically significant. Results Compared with cNAWM, both k bo and AXR BBB were significantly reduced in tumor ( k bo = 3.50 ± 1.18 sec −1 vs. 1.03 ± 0.75 sec −1 ; AXR BBB = 3.54 ± 1.11 sec −1 vs. 1.94 ± 1.04 sec −1 ). Both k bo and AXR BBB showed significantly higher values in NAWM than NAGM ( k bo = 3.50 ± 0.59 sec −1 vs. 2.10 ± 0.56 sec −1 ; AXR BBB = 3.35 ± 0.77 sec −1 vs. 2.07 ± 0.52 sec −1 ). The VOI‐averaged k bo and AXR BBB were also linearly correlated in tumor, NAWM, and NAGM ( r = 0.59). Data Conclusion DCE‐MRI and VEXI showed comparable and correlated WEX BBB in HGG patients, suggesting that the consistence and reliability of these two MRI methods in measuring WEX BBB . Evidence Level 2. Technical Efficacy Stage 1.