Cornea Classic: Bron, Evans, and Smith, "Grading of Corneal and Conjunctival Staining in the Context of Other Dry Eye Tests" (2003).

Dry eye is an increasingly common ocular condition with significant impact on quality of life due to eye discomfort and blurred vision complaints. In addition, the financial burden of dry eye on both patients and society is substantial. Although there has been a recent explosion of research in the field since 2002 with the approval of the first prescription topical treatment (Restasis, Allergan Inc, Irvine CA), dry eye lags behind other ophthalmic conditions where clinically meaningful outcome measures are closely tied with the metrics by which their therapeutics are evaluated. Unfortunately, current practice is such that physicians largely rely on patient symptoms to evaluate dry eye, and these do not always correlate with objective ocular surface and tear film parameters. In patients with severe dry eye, the patient-reported symptoms are likely dampened because of the neurotrophic state of the ocular surface, which accompanies any long-standing inflammatory ocular condition. Therefore, staining of the corneal and conjunctival surface using vital dyes is an invaluable dry eye test to provide information normally not visible during routine slit-lamp examination. The landmark article by Bron, Evans, and Smith published in Cornea in 2003 provides excellent guidance to clinicians to highlight and quantify ocular surface parameters in patients with dry eye. Validation studies correlating conjunctival or corneal staining with tangible quality-of-life parameters and metrics to measure those are needed to verify ocular surface staining as a clinically meaningful dry eye outcome to be used in clinical practice and clinical trials.