“…Factors to think about to guide narrow this list include age, timing of blindness (acute, transient, subacute or chronic), description of "blindness", trauma, associated symptoms and many more. 2 Diagnostic clues from the history (associated features other than blindness) include "Ocular pain" which may be related to acute angle-closure glaucoma, optic neuritis, or keratitis. "Red eye" on the other hand can also be related to keratitis, acute angle-closure glaucoma or even uveitis.…”