Topical tretinoin treatment for severe dry-eye disorders

Despite the diverse causes of dry-eye disorders, the ocular surface epithelia in these diseases all undergo squamous metaplasia, manifested by loss of goblet cells, mucin deficiency, and keratinization. These changes account for tearfilm instability, which leads to various ocular symptoms and corneal complications. This article reviews research in the use of topical tretinoin to treat severe dry-eye disorders. To classify squamous metaplasia into stages, a modified impression cytology technique was used to monitor the therapeutic effect of topical tretinoin ointment (0.01% or 0.1%, w/w) in 22 patients. This population had severe dry-eye disorders, including keratoconjunctivitis sicca, Stevens-Johnson syndrome, inactive ocular pemphigoid, drug-induced pseudopemphigoid, and surgery- or radiation-induced dry eyes. After treatment, clinical improvements were correlated with the reversal of squamous metaplasia as evidenced by the impression cytology technique. Tretinoin may also be effective in treating conjunctival keratinization without dry eyes, as illustrated by a case study. This may represent the first reported attempt to treat ocular surface disorders by reversing diseased epithelium.