Noninvasive assessment of the functional neovasculature in 9L-glioma growing in rat brain by dynamic 1H magnetic resonance imaging of gadolinium uptake.
Pathophysiologic parameters of the functional neovasculature and the blood-brain barrier of 9L-glioma in rat brain were measured noninvasively by dynamic 1H magnetic resonance imaging studies of gadolinium (Gd)-DTPA uptake. Changes of apparent [Gd-DTPA] uptake in time (CT[t]) were analyzed in a slice through the center of 10 9L-gliomas using fast T1 measurements. The distribution of the contrast agent was spatially correlated with the distribution of perfused microvessels as determined by immunohistochemical analysis. This method permits a distinction between perfused and nonperfused microvessels with a disrupted blood-brain barrier. In transverse slices of the whole tumor, a spatial correlation was observed between CT maps and the two-dimensional distribution of perfused microvessels. In the next step, Gd-DTPA uptake rates were spatially related to the perfused microvessel density (Np) or vascular surface area (Sp). In tumor voxels with perfused microvessels, a linear correlation was found between Gd-DTPA uptake rate constants (k values) and Np or Sp. No correlation was observed between k values and the total microvessel density. These are the first data that show a relation between Gd-DTPA uptake rates and parameters of the functional neovasculature in 9L-glioma growing in rat brain. Now that Gd-DTPA uptake studies can be related to parameters of the functional neovasculature, they may be used more efficiently as a prognostic tool before or during therapy.
van der Sanden
B P
BP
Department of Radiology, University Hospital Nijmegen, The Netherlands.
Rozijn
T H
TH
Rijken
P F
PF
Peters
H P
HP
Heerschap
A
A
van der Kogel
A J
AJ
Bovée
W M
WM
D000818:Animals; D001932:Brain Neoplasms / Q000098:blood supply* / Q000378:metabolism; D003287:Contrast Media / Q000493:pharmacokinetics; D019786:Gadolinium DTPA / Q000493:pharmacokinetics; D005910:Glioma / Q000098:blood supply* / Q000378:metabolism; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D009389:Neovascularization, Pathologic / Q000175:diagnosis*; D011522:Protons; D051381:Rats; D011916:Rats, Inbred F344
D003287:Contrast Media; D011522:Protons; D019786:Gadolinium DTPA