Dynamic, contrast-enhanced perfusion MRI in mouse gliomas: correlation with histopathology.
The aim of this study was to develop an MRI protocol to evaluate the growth and vascularity of implanted GL261 mouse gliomas on a 7T microimaging system. Both conventional T(1)- and T(2)-weighted imaging and dynamic, contrast-enhanced T(2)*-weighted imaging were performed on 34 mice at different stages of tumor development. MRI measurements of relative cerebral blood volume (rCBV) were compared to histological assessments of microvascular density (MVD). Enhancement on postcontrast T(1)-weighted images was compared to histological assessments of Evan's blue extravasation. Conventional T(2)-weighted and postcontrast T(1)-weighted images demonstrated tumor growth characteristics consistent with previous descriptions of GL261 glioma. Furthermore, measurements of rCBV from MRI data were in good agreement with histological measurements of MVD from the same tumors. Postcontrast enhancement on T(1)-weighted images was observed at all stages of GL261 glioma progression, even before evidence of angiogenesis, indicating that the mechanism of conventional contrast enhancement in MRI does not require neovascularization. These results provide quantitative support for MRI approaches currently used to assess human brain tumors, and form the basis for future studies of angiogenesis in genetically engineered mouse brain tumor models.
Cha
Soonmee
S
Department of Radiology, New York University School of Medicine, New York, New York, USA.
Johnson
Glyn
G
Wadghiri
Youssef Zaim
YZ
Jin
Olivier
O
Babb
Jim
J
Zagzag
David
D
Turnbull
Daniel H
DH
D000818:Animals; D001810:Blood Volume; D001921:Brain / Q000098:blood supply*; D001932:Brain Neoplasms / Q000098:blood supply* / Q000473:pathology / Q000503:physiopathology; D018450:Disease Progression; D005910:Glioma / Q000098:blood supply* / Q000473:pathology / Q000503:physiopathology; D007089:Image Enhancement; D018810:Magnetic Resonance Angiography / Q000379:methods*; D051379:Mice; D008810:Mice, Inbred C57BL; D023421:Models, Animal; D009389:Neovascularization, Pathologic