Background: To study the long-term efficacy and safety of diode laser cycloablation under a standard protocol in refractory glaucoma.
Methods: A retrospective study involving 42 eyes (39 patients), observed for 36-84 (mean 65.7) months after cycloablation involving 14 burns of 2-W power and 2-s duration, over 270 degrees of the ciliary body.
Results: By final review, mean intraocular pressure (IOP) had dropped by 50.3% from 31.4 +/- 8.8 mmHg before treatment to 15.6 +/- 6.3 mmHg (P < 0.0001). Thirty-seven of the 42 eyes (88.1%) achieved IOP < 22 mmHg. Thirty-five of the 42 eyes (83.3%) eyes achieved IOP reduction > or = 30% from baseline levels. The mean number of antiglaucoma medications per eye dropped from 2.55 +/- 0.83 to 1.71 +/- 1.44 (P = 0.0004). The percentage of eyes requiring oral acetazolamide dropped from 92.9% to 11.9% (P < 0.0001). About 59.6% of eyes required multiple treatment sessions (mean 2.17). Twenty-seven (64.3%) eyes suffered deterioration, 11 (26.2%) maintained stability and 4 (9.5%) exhibited improvement of visual acuity. No relationship between the number of treatment sessions and visual outcome was evident.
Conclusions: This conservative repeatable protocol affords delivery of the minimum dose of photocoagulation necessary to achieve a safe, long-term ocular hypotensive response, while minimizing the risk of serious adverse effects, and is valuable in the difficult treatment of refractory glaucoma.