Modifications of Scheie's operation.

In recent years Scheie's operation (Scheie, I958) has been frequently performed because of its relatively simple technique. The results have been mainly satisfactory in bringing the intraocular pressure to normal in cases of glaucoma. Nevertheless filtration is not always well maintained, for various reasons: (i) Excessive scarring of the conjunctival flap causing closure of the limbal fistula. (2) Exuberant Tenon's capsule, especially in young patients. (3) Blockage of the fistula from within by tags of iris, ciliary processes, vitreous, and occasionally the lens. (4) Re-operations in which the fistula is more prone to closure.