An eye ailment is any type of medical condition that affects the eyes. Common eye ailments include STYE, iritis, and myosis. A STYE is a bacterial infection of the eyelid that causes redness, swelling, and pain. Iritis is an inflammation of the iris, the colored part of the eye, which can cause blurred vision and sensitivity to light. Myosis is a condition in which the pupil of the eye becomes abnormally small, resulting in reduced vision.