Corneal staining patterns in normal non-contact lens wearers

Corneal fluorescein staining was evaluated in 16 subjects over a 2-week period by 2 practitioners. Using a scale of 0 to 4 with 0.5 grade steps, the average duration for an episode of staining above the group median (grade 0.5) was found to be 1.2 +/- 0.4 days. For both eyes, the most prevalent location of staining was the inferior region (50%), followed by the nasal region (20%). Overall, a mean staining grade of 0.5 for the right eye and 0.6 for the left eye was found. Practitioners also demonstrated a difference in grading of 0.1 in the right and left eyes. These data may be most useful in determining the normality of suspect corneal fluorescein staining and its duration until resolution. This study demonstrated a low amount of variability between right and left eyes, and established a good consistency between separate examiners.