Long-term results of ab externo neodymium:YAG cyclophotocoagulation

Neodymium: YAG cyclophotocoagulation (CPC) was performed in 128 eyes of 123 patients with refractory glaucoma. In each eye, 40 burns delivered with energy of up to 7 J were placed 1.5 mm behind the limbus in a 360 degrees pattern. The minimal follow-up period was 24 months, with the mean being 36.9 (range, 24-84; SD, 5.8) months. The mean intraocular pressure was 35.0 (range 23-54; SD, 12.2) mmHg preoperatively, 20.6 (range 15-24; SD, 3.5) mmHg after 1 year, and 20.2 (range 12-24; SD, 8.1) mmHg after 2 years. A total of 25 eyes (19.5%) lost 2 or more lines in visual acuity. Success was defined as a lowering of intraocular pressure by > 30% and a decrease in visual acuity of < 2 Snellen lines. By this definition the success rate was 52.4%. There was no correlation with either the diagnosis, the stage of the disease, or the pigmentation of the trabecular meshwork, although patients with secondary traumatic or uveitic glaucoma tended to be less responsive to CPC. The most common acute complication of treatment was transient corneal edema. Phthisis bulbi developed in 1 eye (0.8%). In conclusion, CPC achieved satisfactory long-term control of intraocular pressure in the majority of patients with severe late-stage glaucoma.