Pigment-dispersion syndrome is an eye disorder that occurs when pigment granules that normally adhere to the back of the iris (the colored part of the eye) flake off into the clear fluid produced by the eye (aqueous humor). These pigment granules may flow towards the drainage canals of the eye, slowly clogging them and raising the pressure within the eye (intraocular pressure or IOP). This rise in eye pressure can cause damage to the optic nerve (the nerve in the back of the eye that carries visual images to the brain). If the optic nerve becomes damaged, pigment-dispersion syndrome becomes pigmentary glaucoma. This happens in about 30% of cases. Pigment-dispersion syndrome commonly presents between the second and fourth decades, which is earlier than other types of glaucoma. While men and women are affected in equal numbers, men develop pigmentary glaucoma up to 3 times more often than women. Myopia (nearsightedness) appears to be an important risk factor in the development of pigment-dispersion syndrome and is present in up to 80% of affected individuals. The condition may be sporadic or follow an autosomal dominant pattern of inheritance with reduced penetrance. At least one gene locus on chromosome 7 has been identified. Pigment-dispersion syndrome can be treated with eye drops or other medications. In some cases, laser surgery may be performed.