The present invention can be a method to allow a user to extract and calculate objective data in a reproducible indicator of the initial evaluation, progression or regression of the activity of choroidal neovascularization or other retinal and subretinal lesions summarized as a single number. The method can be applied to either OCT, FA or both as diagnostic tools depending upon the preference of the user and can be used as the steps of Data Collection, Data and Image Analysis, and Computations. The present invention further provides a user a formula for Approximate Lesion Volume, Flourescein index, the change in the flourescein index, lesion volume index, the active lesion volume change, or the regression factor as well as the severity index. The present invention can also be automated in a program to calculate the desired indexes for the user.