• Topical retinol, tretinoin (all-transretinoic acid) and etretinate (a synthetic retinoid) were used in rabbits to treat experimental xerophthalmia due to vitamin A deficiency. Both 0.2% retinol and 0.1% and 0.2% tretinoin effectively reversed abnormal corneal epithelial keratinization within one to two days and restored corneal clarity within two to four days following topical application three times per day. Etretinate was ineffective in the concentration used (0.2%). In addition, application of tretinoin to one eye effectively reversed xerophthalmic changes in the other eye. Retinol did not have an effect on the other eye.
Hatchell DL, Faculjak M, Kubicek D. Treatment of Xerophthalmia With Retinol, Tretinoin, and Etretinate. Arch Ophthalmol. 1984;102(6):926-927. doi:10.1001/archopht.1984.01040030746036