The diagnosis of pupillary block by intravenous injection of fluorescein.

In 1865, Bowman was the first to recog­ nize the clinical entity of pupillary block, which he observed more frequently after cataract extraction without iridectomy than after cataract extraction with iridectomy. Bowman described this condition only as occurring shortly after discission of a sec­ ondary cataract. From his description it may be surmised that the mechanism in­ volved was obstruction of the flow of aque­ ous by vitreous herniating through the cre­ ated opening in the secondary membrane. Although Bowman believed that the bulging of the iris was caused by oversecretion of aqueous humor, he found that transfixion of the iris usually relieved the increased ocular tension. In 1911, Hudson described pathologic specimens of eyes enucleated for intractable glaucoma after traumatic dislocation of the lens, traumatic subluxation of the lens and discission of a secondary cataract. He rec­ ognized that the aqueous outflow may be ob­ structed directly by vitreous in the anterior chamber, or indirectly by closure of the an­ terior chamber angle by the peripheral iris as a result of pupillary block by vitreous. In 1925, Urbanek reported a case of glau­ coma following discission of a secondary cataract. He observed with the slitlamp a mushroom of vitreous protruding into the anterior chamber and touching the cornea. The anterior chamber had deepened central­ ly, and the peripheral iris was bulging for­ ward. Urbanek concluded that the mechani­ cal obstruction of the pupil by vitreous had created a decrease in the pressure in the an-