Glioblastoma multiforme: MR imaging at 1.5 and 9.4 T after injection of polylysine-DTPA-Gd in rats.
Polylysine-DTPA-Gd, a new MR contrast agent, was injected into the aorta of rats 7 days after C6 glioblastoma was implanted in their brains; MR imaging was performed 3 days later. The imaging was done at two field strengths: (1) 1.5 T with a 3-mm slice thickness and in-plane resolutions of 600 microns and (2) 9.4 T with a 125- or 500-microns slice thickness and in-plane resolutions of 95 microns. In animals injected with polylysine-DTPA-Gd (1 microgram or more per rat), the T1-weighted images and mixed T1, T2 images of the C6 glioblastoma revealed a higher signal intensity at the marginal region between tumor and normal brain than that seen in surrounding normal brain. The central tumor region had a low signal intensity. The concentration of Gd in the C6 glioblastoma, after injection of 1 microgram polylysine-DTPA-Gd per rat, was calculated to be 0.14 mumol/l. The central tumor region also had a low signal intensity in animals that were not injected with the contrast agent, but the margin between tumor and normal brain was resolved poorly, if at all. The polylysine-DTPA-Gd revealed the microvasculature of the C6 glioblastoma in the 125-micron-thick slices obtained at 9.4 T. This is the first study to reveal the utility of the 9.4-T MR imager for examination of glioblastomas in situ and to demonstrate the utility of polylysine-DTPA-Gd as a contrast agent for the definition of the margin between glioblastoma and normal brain tissue.
Kornguth
S
S
Department of Neurology, University of Wisconsin, Madison 53706.
Anderson
M
M
Turski
P
P
Sorenson
J
J
Robins
H I
HI
Cohen
J
J
Rappe
A
A
Markley
J
J
D000818:Animals; D001932:Brain Neoplasms / Q000175:diagnosis*; D003287:Contrast Media; D005682:Gadolinium; D019786:Gadolinium DTPA; D005909:Glioblastoma / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009942:Organometallic Compounds; D004369:Pentetic Acid; D011107:Polylysine; D051381:Rats; D011920:Rats, Inbred WF
D003287:Contrast Media; D009942:Organometallic Compounds; D011107:Polylysine; D004369:Pentetic Acid; D005682:Gadolinium; D019786:Gadolinium DTPA