Corneal staining subsequent to sequential fluorescein instillations.

Liquid fluorescein (2%) was instilled into the inferior cul-de-sac and the precorneal tear film and the cornea were observed utilizing a specialized examination routine. Following the initial fluorescein instillation and observations, sequential fluorescein instillations were performed at five-minute intervals six additional times. The incidence of corneal staining (200 corneas) following the initial instillation of fluorescein was 19%. An additional 23% exhibited staining as a result of the sequential staining process. Five types of staining were classified; the most common forms were those associated with the lid margins. Severe degrees of staining appear to be clinically significant, as suggested by a correlation between severe degrees of staining and contact lens intolerance.