1. A method for quantifying disease progression through retinal health assessment and management comprising: obtaining a first image of a retina at a point in time; generating a first vascular map of the first image of the retina; obtaining a second image of the retina at a later point in time; generating a second vascular map of the second image of the retina; registering the first image and the second image on the basis of the first vascular map and the second vascular map; creating contours on the registered first image, on the second image, on the difference image, or on any combination thereof, that mark the perimeters of the cup and disk regions of the optical nerve head; and using a geometric parameter of the contours to quantify the progression of the disease, the geometric parameter being: the ratio between the surface area of the optic nerve cup and the surface area of the optic nerve disc; the local deviation of the optical nerve cup from a smooth curve; the distances from the optical nerve cup edge to the optical nerve disc edge in inferior, superior, nasal and temporal directions; the ratio of the diameter of the cup in the horizontal direction to the diameter of the disc in the horizontal direction; or the ratio of the diameter of the cup in the vertical direction to the diameter of the disc in the vertical direction.