MR Vascular Fingerprinting with Hybrid Gradient–Spin Echo Dynamic Susceptibility Contrast MRI for Characterization of Microvasculature in Gliomas

SIMPLE SUMMARY: Primary brain tumors, most commonly gliomas, are devastating diseases which in adults are generally fatal. Vascularization is an important aspect of the biological behavior of gliomas, and determining it is valuable for the optimal timing of treatment. Magnetic resonance imaging (MRI) is an excellent non-invasive diagnostic technique for tissue characterization. In this study, we propose an advanced MRI technique, MR vascular fingerprinting based on the dynamic passage of a contrast agent, to gather quantitative information on the major vascular biomarkers of gliomas within an acceptable scan time. This technique was evaluated in six patients with gliomas, obtaining the vascular parameters that deliver information on the vascularity of the tumor. The vessel parameters quantified using the proposed technique were also compared to those quantified using a conventional vessel size imaging technique. This study will significantly contribute to further advances in functional imaging for gliomas. ABSTRACT: Characterization of tumor microvasculature is important in tumor assessment and studying treatment response. This is possible by acquiring vascular biomarkers with magnetic resonance imaging (MRI) based on dynamic susceptibility contrast (DSC). We propose magnetic resonance vascular fingerprinting (MRVF) for hybrid echo planar imaging (HEPI) acquired during the first passage of the contrast agent (CA). The proposed approach was evaluated in patients with gliomas, and we simultaneously estimated vessel radius and relative cerebral blood volume. These parameters were also compared to the respective values estimated using the previously introduced vessel size imaging (VSI) technique. The results of both methods were found to be consistent. MRVF was also found to be robust to noise in the estimation of the parameters. DSC-HEPI-based MRVF provides characterization of microvasculature in gliomas with a short acquisition time and can be further improved in several ways to increase our understanding of tumor physiology.