The histopathology of pigmentary dispersion syndrome with glaucoma

Iris tissue and trabecular meshwork, obtained at time of trabeculectomy, was studied using the light and electron microscope in a 54-year-old woman with pigmentary dispersion syndrome with glaucoma. The specific defect was a loss of the outer epithelial cells of the iris with marked thinning of the remaining outer layers so that the two-cell architecture of the iris epithelium was maintained. In addition, the radial muscle layer was increased in both number and size of muscle fiber. It would appear that the pigmentary dispersion syndrome may represent a congenital or developmental abnormality of the iris epithelium, or both, and that the glaucoma which occasionally occurs in conjunction with this syndrome is of the usual open-angle type.