1. A method for planning a treatment of a patient, the method comprising: displaying, using at least one computer system, a three-dimensional model of at least a portion of at least one coronary artery of the patient; displaying, using the at least one computer system, a first fractional flow reserve for the at least one coronary artery, wherein the first fractional flow reserve is calculated by the at least one computer system; modifying, using the at least one computer system, the three-dimensional model based on information regarding an image of a stent positioned on the three-dimensional model; and displaying, using the at least one computer system, a second fractional flow reserve for the at least one coronary artery, wherein the second fractional flow reserve is calculated by the at least one computer system based on the modified three-dimensional model.