Quantitative Analysis of Dynamic CEST Images to Evaluate Pseudoresponse of Bevacizumab Treatment

Motivation: Bevacizumab is widely used for treating high-grade gliomas, yet conventional MRI sequences often show limitations in effectively monitoring the therapeutic response. Goal(s): The study aims to apply structural and advanced MRI techniques (APTw, CEST@2ppm, T1 and T2 mapping) to assess changes in tumor and surrounding edema, focusing on distinguishing true treatment effects from pseudoresponse. Approach: We developed a robust quantitative approach for analyzing follow-up scans of patients. Response maps and statistical comparisons were performed to evaluate therapeutic effects. Results: APTw and CEST@2ppm are more accurate in monitoring tumor, outperforming T1 and T2 maps in identifying pseudoresponse, and thus improving diagnostic accuracy. Impact: This study provides a practical approach for robust and accurate evaluation of Bevacizumab treatment, demonstrating the superiority of CEST imaging in identifying pseudoresponse. It shows potential to complement existing clinical protocols, enabling more precise diagnoses for glioma patients.