Pigment dispersion syndrome and pigmentary glaucoma

In pigment dispersion syndrome (PDS), an autosomal dominant disorder, iridozonular friction mechanically disrupts the iris pigment epithelium, dispersing pigment granules throughout the anterior segment. The classic clinical triad consists of corneal pigmentation (Krukenberg spindle): radial, slit-like, mid-peripheral iris transillumination defects, and trabecular hyperpigmentation. The iris insertion is typically posterior and the peripheral iris is often concave. It is a leading cause of glaucoma in persons under age 40. Eyes with PDS differ from normal in having an iris concavity which increases with accommodation, a more posterior iris insertion, increased iridolenticular contact, and an increased incidence of lattice degeneration of the retina. The clinical signs begin to reverse with the onset of presbyopia and understanding of the mechanism underlying the iris pigment liberation allows planning treatment not only to lower intraocular pressure, but also to reverse the pathophysiology.