A method, data processing facility and program storage device for quantitative analysis on medical image data of a bifurcated tubular organ which involves processing the medical image data to identify contours of the bifurcated tubular organ. The contours are used to determine a Polygon of Confluence amongst the bifurcated tubular organ. The Polygon of Confluence is used to determine at least one parameter value characterizing geometry of the bifurcated tubular organ. The at least one parameter value is outputted to a user for angiography purposes. The at least one parameter value can include at least one diameter value of the bifurcated tubular organ, at least one angle value between parts of the bifurcated tubular organ, and at least one reference diameter value for the bifurcated tubular organ, the at least one reference diameter value compensating for damage to the bifurcated tubular organ.
