β Scribed by Y.R. Kim; M.D. Savellano; D.H. Savellano; R. Weissleder; A. Bogdanov Jr.
No coin nor oath required. For personal study only.
It is important to evaluate the tumor interstitial volume fraction that is accessible for drug accumulation during the distribution phase in order to determine the potential efficacy of cancer chemotherapy. In this study, we performed simulations of magnetic resonance imaging (MRI) signal intensity using a twoβcompartment tissue model for quantitative analyses of absolute interstitial volume measurements while we experimentally characterized a mouse tumor model with a dual MR contrastβagent method. Previously, consecutive intravenous injections of a strictly intravascular T~1~ contrast agent followed by an extravasating agent were used as a strategy for the quantification of both relative blood volume (Rel_BV) and relative interstitial volume (Rel_ITST) (Weissleder et al. Eur J Cancer 1998;34:1448β1454; Bogdanov et al. Neoplasia 1991;1:438β435). In the current study, we demonstrate that this approach can be further improved, and that it enables one to accurately evaluate both relative and absolute interstitial volumes. The animal data indicated that a significant difference exists between the absolute interstitial volume fractions of subcutaneously implanted MDA PCa 2b tumor and skeletal muscle tissue (27.5 Β± 9.1% and 15.9 Β± 0.7%, respectively (P < 0.05)), while only a minor difference was found for the absolute blood volumes (Abs_BV) (Kim et al. Magn Reson Med 2002;47:1110β1120) of these tissues. Magn Reson Med 52:485β494, 2004. Β© 2004 WileyβLiss, Inc.
π SIMILAR VOLUMES
The goal of this study was to determine the degree to which vascular water exchange and blood flowing into an imaging slice affect the accuracy of blood volume measurements of brain and tumor tissue when using intravascular T(1) contrast agents. The study was performed using 2D and 3D gradient-echo