[Comparison of corneal and conjunctival rose bengal staining before and after punctal occlusion].

PURPOSE: In severely tear-deficient dry eye patients whose puncta had been occluded, corneal and conjunctival rose bengal (RB) staining were graded and compared to before occlusion.

SUBJECTS AND

METHODS

Subjects were 17 eyes of 13 severely tear-deficient dry eye patients whose puncta had been successfully occluded (corneal fluorescein staining showed A 0 D 0 after occlusion). Corneal and conjunctival RB staining were graded 0, 1, 2 or 3, according to severity [B 1] at the cornea and at the temporal and nasal bulbar conjunctiva. The scores were then compared to those before punctal occlusion. To enable comparison of pre- and post-occlusion ocular surface concentrations of RB [B 2], post-occlusion concentration was adjusted by absorbing tears from the conjunctival sac with Schirmer's test paper until the lower meniscus height was equal to that before occlusion, as monitored by video-meniscometer. RB dye was then instilled into the patients conjunctival sac.

RESULTS

RB staining score at the cornea decreased significantly; in contrast, no significant improvement was found at the nasal and temporal conjunctiva (p = 0.0025, p = 0.05, p = 0.7, respectively, Wilcoxon test).

CONCLUSION

In accordance with the basic interpretation of RB staining, these results imply that RB positive staining [B 3] on the conjunctival surface is caused by a factor other than aqueous deficiency.