title: Evaluation of human brain tumor heterogeneity using multiple T1-based MRI signal weighting approaches.
abstract: Vascular-space-occupancy (VASO) MRI without contrast injection was explored for imaging cerebral blood volume (CBV) and tissue heterogeneity in gliomas (n = 10). VASO contrast complemented contrast-enhanced T(1)-weighted (GAD-T(1)w), FLAIR and T(1)w magnetization-prepared-rapid-gradient-echo (MPRAGE) images. High-grade gliomas showed a VASO-outlined hyperintense zone corresponding to long-T(1) regions in MPRAGE and to nonenhancing regions in GAD-T(1)w images. FLAIR, MPRAGE, and VASO data were used to segment tumors into multiple zones of different T(1). After removal of known resection areas using pre- and postsurgical MRI, the volume of overlap between the hyperintense VASO-zone and the long-T(1) MPRAGE zone correlated with that of GAD-T(1)w enhancement (R(2) = 0.99) and tumor grade. Based on these correlations, this remaining long T(1) overlap area was tentatively assigned to necrosis. In one promising case the collective T(1)-weighted approach accurately identified a low-grade glioma despite the presence of contrast enhancement in GAD-T(1)w images consequential to chemoradiation-associated treatment effect. The results suggest that this collective T(1)-weighted approach may provide useful information for regional assessment of heterogeneous tumors and for guiding treatment-related decisions in patients with gliomas.
authors.affiliation: Russell H. Morgan Department of Radiology and Radiological Science, Neuroscience Section, Division of MR Research, Johns Hopkins University, 720 Rutland Avenue, Baltimore, MD 21205, USA.
authors.forename: Manus J
authors.initials: MJ
authors.lastname: Donahue
authors.forename: Jaishri O
authors.initials: JO
authors.lastname: Blakeley
authors.forename: Jinyuan
authors.initials: J
authors.lastname: Zhou
authors.forename: Martin G
authors.initials: MG
authors.lastname: Pomper
authors.forename: John
authors.initials: J
authors.lastname: Laterra
authors.forename: Peter C M
authors.initials: PC
authors.lastname: van Zijl
mesh_terms: D000465:Algorithms; D001932:Brain Neoplasms / Q000473:pathology*; D018450:Disease Progression; D005910:Glioma / Q000473:pathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D012044:Regression Analysis