The Cup-to-Disc Ratio (CDR) measures the ratio between the areas of the cup and the disc of the optic nerve, aiding in the identification of glaucoma-related alterations.
To utilize this feature, select the desired image for analysis from the gallery. Next, click on the editing icon located at the top right corner of the screen, followed by selecting the CDR option on the bottom menu. This feature can also be found on the editing screen.
Usually, healthy eyes follow the rule Inferior ≥ Superior ≥ Nasal ≥ Temporal.