Determination of adequate measurement times for super-resolution characterization of tumor vascularization

Abstract

Current advances in super-resolution imaging of microvessels are promising for the diagnosis and therapy monitoring of cancer. However, to implement super-resolution imaging of microvessels in clinical practice, the trade-off between the concentration of microbubbles (MB) appropriate to detect and track single MB, and reasonable short measurement times has to be resolved. Here, we investigate the MB concentration best suitable for, at once, a reliable detection of the MB and short measurement times. We further estimate the measurement times necessary to adequately reconstruct the microvessel trees in tumor models. For this, we chart the tracks of the moving MB within the tumors and evaluate the information increment as a function of acquired frames. We show that for the practical concentration of 2×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">8</sup> MB/ml allowing super-resolution, 45 s to 170 s are necessary for a 90% mapping of the microvessels. For the estimation of an equivalent to the clinically relevant parameter relative blood volume (rBV) even 30 s are sufficient.