Distichiasis, Trichiasis, Ectopic cilia

These conditions all involve eyelashes rubbing on the cornea (clear surface of the eye).

Distichiasis is where additional cilia (lashes) grow out of the opening of the tarsal glands. These lubricating glands are situated along the edge of the eyelid between the normal cilia and the inside edge of the lid.
Ectopic cilia is a slight variation where the abnormal cilia emerge through the inside lining off the eyelid.
Trichiasis is a result of normal lashes and hairs growing in an abnormal direction toward the cornea.
Clinical signs of these conditions include epiphora (excessive tears) and tear staining, pain and redness of the eye, and in chronic cases ulcers (damage to the surface) of the cornea.

Ectopic cilia are treated by surgical removal of the cilia and affected tarsal gland.
Microcryoepilation is the treatment of choice for districhiasis. This technique involves freezing the tarsal gland using a fine nitrous oxide probe. Electroepilation, where the gland is destroyed by electrolysis using a fine electrical probe, may also be used to treat districhiasis.
Trichasis can be treated with a combination of the above methods and removal of sections of skin around the eye to pull the cilia and hair away from the cornea.