Indications:
(1) keratoconjunctivitis sicca.
(2) corneal infections
(3) chemical exposures to the eye
Procedure:
(1) A 1-2% solution or strip impregnated with fluorescein dye is instilled in each eye.
(2) The eye is examined 3 minutes after instillation using incident light is passed through a cobalt blue filter.
(3) The examiner uses a biomicroscope with a Wratten #11 or #12 yellow barrier filter to evaluate the staining in each corneal sector.
Corneal sectors: 5 (central, superior, lateral, medial, inferior) for each eye
Grading: 0 (no staining) to 3 (confluent)
Score: sum of all 5 sectors
Interpretation:
• minimum score: 0
• maximum score: 15
• A score >= 4 is abnormal and reflects injury to the corneal surface.
Limitations:
• Some staining may be seen in normal eyes and is more prominent in the morning.
• Sequential use of the stain results in more staining of the cornea. Comparison of results after sequential use with results after a single use may result in variable results.
