Embodiments disclose systems and methods that aid in screening, diagnosis and/or monitoring of medical conditions. The design includes a system and method for accessing retinal images related to a patient, each retinal image including a plurality of pixels. For each of the retinal images, the system designates a first set of the plurality of pixels as active pixels including interesting retinal image regions and computes a first vector of numbers comprising pixel-level descriptors for each of the active pixels. The system computes a second vector of numbers for each of the retinal images and provides a second classification using supervised learning.