Pigment dispersion syndrome: an eye condition in which the pigment from the iris (the part of the eye that determines eye color) rubs off. In some people this loose pigment clogs the drainage channels for fluid in the eye, leading to a type of glaucoma known as pigmentary glaucoma. As with any type of glaucoma, there is elevated pressure within the eye (elevated intraocular pressure) that can damage the optic nerve that transmits vision signals to the brain. Pigment dispersion syndrome may not cause any symptoms or signs. In some people, it may cause blurred vision or blank spots in the field of vision. Unlike other forms of glaucoma, pigmentary glaucoma is more often diagnosed in younger people (in their 20s or 30s).