Advanced and Amplified BOLD Fluctuations in High-Grade Gliomas

Background: Glioma grade along with patient's age and general health are used for treatment planning and prognosis. PURPOSE: To characterize and quantify the spontaneous blood oxygen level-dependent (BOLD) fluctuations in gliomas using measures based on T-2*-weighted signal time-series and to distinguish between high- and low-grade gliomas. Study Type: Retrospective. Subjects: Twenty-one patients with high-grade and 13 patients with low-grade gliomas confirmed on histology were investigated. Field Strength/SequenceDynamic T2*-weighted (multislice single-shot echo-planar-imaging) magnetic resonance imaging (MRI) was performed on a 3T system with an 8-element receive-only head coil to measure the BOLD fluctuations. In addition, a dynamic T-1-weighted (3D fast field echo) dynamic contrast-enhanced (DCE) perfusion scan was performed. Assessment: Three BOLD measures were determined: the temporal shift (TS), amplitude of low frequency fluctuations (ALFF), and regional homogeneity (ReHo). DCE perfusion-based cerebral blood volume (CBV) and time-to-peak (TTP) maps were concurrently evaluated for comparison. Statistical Tests: An analysis-of-variance test was first used. When the test appeared significant, post-hoc analysis was performed using analysis-of-covariance with age as covariate. Logistic regression and receiver-operator characteristic curve analysis were also performed. Results: TS was significantly advanced in high-grade gliomas compared to the contralateral cortex (P=0.01) and low-grade gliomas (P=0.009). In high-grade gliomas, ALFF and CBV were significantly higher than the contralateral cortex (P=0.041 and P=0.008, respectively) and low-grade gliomas (P=0.036 and P=0.01, respectively). ReHo and TTP did not show significant differences between high- and low-grade gliomas (P=0.46 and P=0.42, respectively). The area-under-curve was above 0.7 only for the TS, ALFF, and CBV measures. Data Conclusion: Advanced and amplified hemodynamic fluctuations manifest in high-grade gliomas, but not in low-grade gliomas, and can be assessed using BOLD measures. Preliminary results showed that quantification of spontaneous fluctuations has potential for hemodynamic characterization of gliomas and distinguishing between high- and low-grade gliomas. Technical Efficacy: Stage 5