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T 1 snapshot flash measurement of rat brain glioma: kinetics of the tumor‐enhancing contrast agent manganese (iii) tetraphenylporphine sulfonate

1992; Wiley; Volume: 27; Issue: 2 Linguagem: Inglês

10.1002/mrm.1910270202

1522-2594

Mathias Hoehn‐Berlage, David G. Norris, Kurt H. Bockhorst, Ralf‐Ingo Ernestus, O. Kloiber, Petra Bonnekoh, Dieter Leibfritz, Konstantin‐Alexander Hossmann,

Electron Spin Resonance Studies

Abstract The ultrafast inversion recovery snapshot FLASH technique was used to determine the kinetics of the contrast agent manganese (III) tetraphenylporphine sulfonate (MnTPPS) in experimental brain tumors in rats. In the first part of the investigation this technique was validated with the conventional inversion recovery spin‐echo method by comparing in vivo T 1 data of a normal rat brain. Agreement between T 1 values obtained from both techniques was complete, as tested for a large number of pixels in identical coronal slices. In the second part the fast IR snapshot FLASH method was applied to study the effect of the NMR contrast agent MnTPPS on the T 1 relaxation time of experimental gliomas in rat brains. T 1 of normal brain tissue (1024–1035 ms), tumor (1217 ms), and edema (1199 ms) was determined with the inversion recovery version of the snapshot FLASH imaging technique. After intraperitoneal injection of MnTPPS (0.25 mmol/kg body wt) T 1 decreased exponentially to 56% of control in tumor and to 62% in muscle. In normal and edematous brain tissue no significant changes in T 1 were observed up to 5 h after injection of the contrast agent. Once the T 1 contrast between tumor and peritumoral brain tissue had reached a saturation, the enhancement persisted for several hours to days. Therefore application of this contrast agent resulted in a sharp demarcation between glioma and peritumoral edema.