Quantitative trabeculectomy.

The technique and results of a trabeculectomy are presented where the desired final intraocular pressure (IOP) is obtained by means of adjusting the thickness of sclerocorneal tissue removed to the initial pressure. The procedure was used in 35 eyes with all types of glaucoma and pre-operative pressures of up to 50 mmHg. In 78.3% of cases one operation was sufficient to control the IOP without additional medication. Two eyes had to be reoperated on, and 7 more needed additional pressure-lowering medication. The overall success rate, therefore, rose to 97.3%. The only failure occurred in an eye with irreducible acute angle-closure glaucoma where malignant glaucoma complicated the trabeculectomy. Complications included hyphaema (3), shallow anterior chamber (7)--with or without choroidal detachment--and transient rise in the IOP. All complications subsided with conservative therapy.