Glioblastoma multiforme: MR imaging at 1.5 and 9.4 T after injection of polylysine-DTPA-Gd in rats

AJNR Am J Neuroradiol. 1990 Mar-Apr;11(2):313-8.

Abstract

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.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Brain Neoplasms / diagnosis*
  • Contrast Media
  • Gadolinium
  • Gadolinium DTPA
  • Glioblastoma / diagnosis*
  • Magnetic Resonance Imaging / methods*
  • Male
  • Organometallic Compounds*
  • Pentetic Acid*
  • Polylysine*
  • Rats
  • Rats, Inbred WF

Substances

  • Contrast Media
  • Organometallic Compounds
  • Polylysine
  • Pentetic Acid
  • Gadolinium
  • Gadolinium DTPA