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World Health Organisation classification of xerophthalmia, based on clinical ophthalmological features. Shaded cells correspond to retinal pathology.
| Xerophthalmia stage | WHO abbreviation |
| Nyctalopia | XN |
| Conjunctival xerosis | X1A |
| Bitot’s spots | X1B |
| Corneal xerosis | X2 |
| Corneal ulceration/keratomalacia involving < 1/3 of the cornea | X3A |
| Corneal ulceration/keratomalacia involving > 1/3 of the cornea | X3B |
| Corneal scarring | XS |
| Xerophthalmic fundus | XF |
