Anterior pars plana vitrectomy in ciliary and iris block glaucoma.

Ciliary and iris block glaucoma in aphakic and phakic eyes is characterized by the accumulation of aqueous humor in the vitreous cavity causing an increase in vitreous volume, a flattening of the anterior chamber, and an elevation of intraocular pressure. As vitreous blocks the space between the ciliary body and the iris or lens, respectively, an anterior vitrectomy via the pars plana is the logical surgical approach. This operation was performed in one phakic and 15 aphakic eyes with so-called pupillary block. The anterior chamber retained a normal depth in each case. Post-operatively the vitreous was found to be completely removed from the posterior chamber and the epiciliary space, rendering a free communication between the ciliary body and the posterior and anterior chamber. Early surgery in aphakic eyes with a flat anterior chamber resulted in a prompt normalization of intraocular pressure, whereas eyes with a block duration of over 4 weeks were at high risk of developing a secondary outflow resistance probably due to chronic angle closure.