The CABI Cancer Imaging Group has developed a new technique named  convectionMRI, which allows the velocity of fluid flowing through tumours, outside blood vessels, to be mapped. This technique has allowed us to gain fundamental insights into the tumour fluid mechanics and the distribution of interstitial fluid pressure (IFP), which we aim to use to predict the delivery of therapeutic molecules. Figures 1 to 3 show examples of the type of images that we have acquired using the technique, which we have combined with measurements of vascular perfusion using arterial spin labeling (ASL).
Streamline diagrams showing the path of fluid through three example tumours

Figure 1: Streamline diagrams showing the path of fluid through three example tumours, acquired using convectionMRI. The colour scale corresponds to the velocity of the fluid.

Maps of tumour vascular perfusion, convection and Gd-DTPA uptake.

Figure 2: (a) Maps of tumour vascular perfusion in a cross-section through a subcutaneous tumour xeongraft model (SW1222 (left) and LS174T (right)), measured using arterial spin labelling (ASL). Streamlines from convectionMRI analysis are overlaid, showing interstitial convection emanating from regions with high blood flow. (b) MRI signal enhancement in a tumour xenograft following slow infusion of a contrast agent. The agent accumulates in a region marked with an arrow, between the two lobes of the tumour, which, according to the map in (c), has low vascular perfusion. (d) Streamline maps from convectionMRI reveal convection patterns through the tumour interstitium, in opposite directions through each tumour lobe, that converge on the region marked with the arrow. This example demonstrates the potential that convectionMRI and ASL have, when combined, for the prediction of drug delivery to tumours.

Figure 3: Animation showing the path of fluid through the tumour interstitium (grey lines), overlaid on a vascular cast.

Associated publications:

Walker-Samuel S, Ramasawmy R, Wells J, Siow B, Johnson SP, Pedley RB, Lythgoe MF, Investigating tumour interstitial convection currents using extra-vascular convection (EVAC) MRI, Proceedings of the British Chapter of the International society for Magneitc resonance in Medicine, 2011 (Manchester). [PDF]

Page last modified on 18 jan 12 17:35