In-vivo quantitative analysis of the angiogenic microvasculature in tumor-bearing rats using multiple scattering

Angiogenesis is the process of growth of capillary blood vessels from existing vessels. It is dysregulated in many diseases, including cancer. Characterization the microvasculature in vivo in terms of micro-architectural features such as density, anisotropy and tortuosity could enhance the specificity of ultrasound cancer diagnosis. A method based on the random matrix theory to distinguish between angiogenic microvasculature in a tumor and in healthy tissue using ultrasound multiple scattering from microbubbles injected into the vasculature has been proposed. It measures the diffusion constant (D) and the scattering mean free path (L) of the medium using an inter-element matrix acquired with a linear array transducer. These results are based on a study conducted on 16 tumor-bearing rats. L for healthy tissue (L = 106.54 μm ± 5.08 μm) and tumor (L = 43.58 μm ± 3.97 µm) were significantly different (unpaired t-test, p < 0.05). In vitro experiments and simulations were also conducted with contrast agent micr...