[Treatment of refractory glaucomas by transscleral cyclophotocoagulation using semiconductor diode laser. Analysis of 50 patients followed-up over 19 months].

PURPOSE: To evaluate the effects of transscleral cyclophotocoagulation with the diode laser for refractory glaucoma with respect to intra-ocular pressure, reduction of medical therapy and complications.
METHODS: The diode laser system (Iris Medical Instrument, Oculight SLX) was used to treat 50 eyes of 47 patients with therapy resistant glaucoma and a poor prognosis with filtering surgery. All eyes had maximal hypotonic therapy and 40 (82%) patients were using carbonic anhydrase inhibitors. Laser energy was delivered to the eye through a quartz glass fiber optic probe [13 to 20 spots over 270 degrees using 3.5 J (1.75 W x 2.0 sec)]. The mean follow-up was 19.4 +/- 9.1 months (from 12 to 29 months).
RESULTS: Intra-ocular pressure significantly decreased from mean baseline 32.4 +/- 9.1 mmHg to 19.7 +/- 8.1 mmHg at the end of the follow-up (p < 0.001). An intra-ocular-pressure below 20 mmHg was obtained in 66% of the eyes. In 13 patients the carbonic anhydrase inhibitors were discontinued. Six of the 8 painful eyes had pain relief. Visual acuity decreased in 17 (34%): cataract progression in 5 eyes, uncontrolled intra-ocular-pressure in 4 eyes, glaucoma progression despite controlled intra-ocular-pressure in 3 eyes, corneal dystrophy in 3 eyes. Chronic uveitis occurred in 5 (10%) eyes. No conjonctival, scleral or direct lens damage was detected.
CONCLUSION: Contact transscleral cylophotocoagulation with the diode laser system can be successfully used to reduce intra-ocular-pressure in therapy resistant glaucoma. The incidence of complications is low with no loss of vision related to cyclodestruction.