1. A method for vascular assessment comprising: receiving a plurality of 2D angiographic images of a portion of a patient's vasculature having a stenotic lesion or plaque; generating an anatomical model of the patient's vasculature using the received plurality of 2D angiographic images; determining a flow characteristic of blood flow through the anatomical model; performing a plurality of iterations of: modifying the anatomical model by modifying measurements of the vasculature at one or more locations along one or more vessels of the patient's vasculature; determining a modified flow characteristic of blood flow through the modified anatomical model; calculating an index indicative of vascular function based, at least in part, on the first flow characteristic of blood flow through the anatomical model and the modified flow characteristic of blood flow through the modified anatomical model; generating and outputting, to an electronic storage medium or display, a report of a modified anatomical model from the one or more iterations, for which the modified flow characteristic of blood flow through the modified anatomical model maximizes the index indicative of vascular function; and determining and outputting, to an electronic storage medium or display, indicia of one or more treatment options based on the report.