Ocular melanosis

Ocular melanosis (OM), also known as ocular melanocytosis or melanosis oculi, is a disease of the eye which in dogs is almost found exclusively in the Cairn Terrier. Until recently it was known as pigmentary glaucoma. The disease is caused by an increase of melanocytes in the iris, sclera, and surrounding structures. This infiltration of pigment can block the part of the eye through which fluid drains. The increased fluid in the eye leads to increased pressure, which is glaucoma. Humans can also have the disease, sometimes known as pigment dispersion syndrome.