Surgical removal of congenital pupillary-iris-lens membrane.

A pupillary membrane in a case of congenital pupillary-iris-lens membrane with goniodysgenesis was surgically peeled from the lens without causing cataract formation. Histopathology revealed ectopic iris. The ectopic iris found in this condition differentiates congenital pupillary-iris-lens membrane with goniodysgenesis as an entity from persistent pupillary membrane, hereditary goniodysgenesis, and Rieger's anomaly. We suggest that congenital pupillary-iris-lens membrane with goniodysgenesis is a neurocristopathy. The finding of ectopic iris muscle is consistent with avian chimera experiments that have suggested that iris sphincter muscle is derived from the neural crest, not neural ectoderm. Membranes in this condition can be successfully removed when they cause vision loss and amblyopia.