Steady-State Quantification of &[Delta]R2 (SSTAR2) with Combidex for Measuring Cerebral Blood Volume
Kelly D, McCreary C, Tyson R, Kirk D, Foniok T, Dunn J
University of Calgary, University of Calgary
Angiogenesis research requires non-invasive methods for studying the growth and regression of vessels. This study quantifies the relaxation rate R2 before and after infusion of the super-paramagnetic susceptibility agent, Combidex and relates the changes to serum Combidex to quantify CBV. We use T2 imaging with short echo times to ensure selective sensitivity to the microvasculature. Practical issues are studied such as the effect of changing echo time and the differences observed when analyzing the data with single or multi-exponential models. The greatest precision was obtained with a single-exponential model, 3ms interecho spacing and 128 echoes. CBV was measured at 2.1%v/v.