Table 1.

List of the quantitative microvessel morphological parameters

Biomarkers	Definition and calculation
NB	Numbers of branch points: defined as any node that is connected to three or more vessel segments
NV	Number of vessel segments
VD	Vessel density: defined as the proportion of vessel area with blood flow over the total area measured
D (mm)	Vessel diameter (Dmean, Dmax): defined as two times of the minimum distance between the vessel centerline and the vessel border
τ	Vessel tortuosity (τmean, τmax): Distance metric measures vascular tortuosity
MD	Murray’s deviation: diameter mismatch, defined as the deviation from Murray's law, increases in the vasculature network of malignant tumors
mvFD	Microvessel fractal dimension: A unit-less geometrical feature that is a marker of microvascular complexity
BA (°)	Bifurcation angle: refers to the angle between two daughter vessels

Note ‒ Subscript mean and max indicate the corresponding mean and maximum value, respectively