Utility of simultaneously acquired gradient‐echo and spin‐echo cerebral blood volume and morphology maps in brain tumor patients

Abstract

An interleaved gradient-echo (GE) / spin-echo (SE) EPI sequence was used to acquire images during the first pass of a susceptibility contrast agent, in patients with brain tumors. Maps of 1) GE (total) rCBV (relative cerebral blood volume), 2) SE (microvascular) rCBV, both corrected for T 1 leakage effects, and 3) (R 2 */R 2), a potential marker of averaged vessel diameter, were determined. Both GE rCBV and R 2 */R 2 correlated strongly with tumor grade (P 0.01, P 0.01, n 15), while SE rCBV did not (P 0.24, n 15). When the GE rCBV data were not corrected for leakage effects, the correlation with tumor grade was no longer significant (P 0.09, n 15). These findings suggest that MRI measurements of total blood volume fraction (corrected for agent extravasation) and R 2 */R 2 , as opposed to maps of microvascular volume, may prove to be the most appropriate markers for the evaluation of tumor angiogenesis (the induction of new blood vessels) and an-tiangiogenic therapies.

Whole-brain mapping of venous vessel size in humans using the hypercapnia-induced BOLD effect

“…Thus, VSI is a strong indicator for angiomas and gliomas and permits evaluation of morphological changes in tumor vasculature in response to therapy (Quarles and Schmainda, 2007). VSI correlates strongly with tumor grade (Donahue et al, 2000) and can also be applied to characterize stroke (Bosomtwi et al, 2008). VSI was validated with stereologic measurements on histology data (Troprès et al, 2004) and micro-CT angiography (Ungersma et al, 2008).…”

Dynamic contrast-enhanced susceptibility-weighted perfusion MRI (DSC-MRI) in a glioma model of the rat brain using a conventional receive-only surface coil with a inner diameter of 47mm at a clinical 1.5T scanner

“…Routine contrast-enhanced, dynamic susceptibilityweighted MR imaging has already proven to be of clinical value, in order to distinguish between different tumor types of the human brain (Boxerman et al, 2006;Donahue et al, 2000;Hartmann et al, 2003;Law et al, 2006;Provenzale et al, 2002). The purpose of this study was to develop a setup for advanced tumor mapping using DSC-MRI, at a clinical MRI scanner with standard surface coils in a rat model.…”

Vessel size imaging using low intravascular contrast agent concentrations

“…Regional tumor heterogeneity and the invasiveness of the biopsy limit however this approach for routine examinations. Recently, magnetic resonance methods based on susceptibility contrast were shown to have potential for mapping blood volume and microvascular morphologic parameters such as vessel size [1][2][3][4][5]. Their main interest lies in the fact that information on the microvasculature can be obtained non-invasively over the whole tumor.…”