Slit-lamp examination

A slit lamp is a microscope that magnifies and illuminates the front of your eye with an intense line of light. Your doctor uses this light to examine the eyelids, lashes, cornea, iris, lens and fluid chamber between your cornea and iris

When examining your cornea, your doctor may use a dye, most commonly fluorescein (flooh-RES-een), to color the film of tears over your eye and see any damaged cells on the front of your eye. Your tears wash the dye from the surface of your eye fairly quickly.