Edward J. Curran and the concept of relative pupillary block.

The historical development of the concept of relative pupillary block and its role in the pathogenesis of angle-closure glaucoma is reviewed. Prior to 1920, the mechanism of action of iridectomy in glaucoma was not understood, its indications unclear, and its technique unsatisfactory. Edward J. Curran's original statement of this concept, and its cure by peripheral iridotomy, were outstanding contributions to the treatment of glaucoma. The controversial responses of other ophthalmologists are related.