Preparation of artificial vascularised tissue and the indirect determination of its void volume using μCT

The non-invasive determination of the vasculature volume would be very useful in many fields of medicine such as oncology and implantation. The purpose of this research was, therefore, to develop a methodology to investigate vascularisation in phantoms using microcomputed tomography (μCT) without having to visualise the single vessels. Epoxy resin and cotton candy were used to form the phantoms with microchannels. The size of the channels was measured via microscopy and the proportion of the void volume (PVV) was calculated. The phantoms were placed in contrast agent solutions of different concentrations and scanned in μCT. The mean CT numbers of the phantoms were calculated with the Amira software and displayed as a function of the determined PVV and the contrast agent concentration (CAC). The fabricated microchannels had the size of biological capillaries (diameter: 5 µm to 15 µm) and the phantoms showed a microchannel density of 5 to15 microchannels per mm². With an increasing CAC, the CT numbers increased significantly. Additionally, the phantoms with a higher PVV also had a higher CT number. The CT numbers and the PVV correlated moderately together, but significantly. The slope of the regression line increased with an increasing CAC.