Technologies are provided to estimate in vivo aqueous humor outflow for a subject. The method can include: preparing a virtual casting of the outflow network of the subject by use of background subtraction and contrast enhancement tracing network terminal branches in said reduced virtual casting obtaining Doppler data for at least some of the terminal branches, to calculate a fluid velocity within each of such terminal branch then pairing each fluid velocity for each such terminal branch with a measurement of cross-sectional area for that terminal branch, thereby to provide a plurality of volumetric flow values and integrating over the plurality to obtain a volumetric estimate of aqueous humor outflow for the subject.
