A form of open-angle glaucoma incidental to pigment dispersion syndrome. It is marked by abnormal accumulation of pigment cells in the trabecular meshwork, on the zonules, crystalline lens, and the corneal endothelium. It leads to the blockage of the trabecular meshwork and an increase of intraocular pressure (IOP). Prolonged high IOP damages the optic nerve causing a painless and irreversible loss of vision.