Abstract
Purpose: :
Does is matter when you view conjunctival lissamine green staining? Previous studies have shown differences in lissamine green staining appearance with respect to time (1, 2, 3, 4 and 5 minutes), establishing optimal viewing at the 2 min time point. We compared the appearance of staining between 0 min and 2 min time points.
Methods: :
30 subjects (ages 21-63, mean age 44 years old; 14 males, 16 females) were stained with lissamine green strips. The staining was graded (grades 0 to 4) in six conjunctival zones. The time points were at 0 min and 2 min.
Results: :
The mean grades at the 0 min statistically significant higher than at 2 min for all zones: temporal (0 minutes mean 1.4 SD 1.44, 2 min mean 0.10 SD 0.35; p<.0000), superior temporal (0 minutes mean 1.9 SD 1.47, 2 min mean 0.53 SD 0.65; p<.0000), inferior temporal (0 minutes mean 1.8 SD 1.44, 2 min mean 0.43 SD 0.65; p<.0000), superior nasal (0 minutes mean 2.4 SD 1.17, 2 min mean 1.0 SD 0.99; p<.0000), inferior nasal (0 minutes mean 2.4 SD 1.2, 2 min mean 1.3 SD 1.35; p<.0000), nasal (0 minutes mean 1.4 SD 1.38, 2 min mean 0.15 SD 0.44; p<.0000).
Conclusions: :
Common protocols for fluorescein staining usually entails immediate viewing after instillation. Immediate viewing (0 min) after instillation of lissamine green resulted in higher mean grades than at the 2 min time point. Past studies showed highest mean grades were at the 2 min time point, but grades at 0 min have not been studied. This study suggests a false staining appearance occurs upon immediate installation of lissamine green.
Keywords: cornea: tears/tear film/dry eye • conjunctiva • cornea: clinical science