Transscleral diode laser cyclophotocoagulation as primary and secondary surgical treatment in primary open-angle and pseudoexfoliatve glaucoma - Long-term clinical outcomes

Background: Transscleral diode laser cyclophotocoagulation (TDLC) has been used successfully in the treatment of refractive glaucoma. However, little is known about TDLC as a primary or secondary surgical procedure in1 primary open-angle and pseudoexfoliative glaucoma. Methods: In a retrospective chart review we analyzed 90 eyes (48 OD/42 OS) in 90 patients (mean age 75 years, range 60-92 years; 51 men/39 woman) with primary open-angle glaucoma (n=66) and pseudoexfoliative glaucoma (n=24) who consecutively underwent TDLC with a minimum follow-up of 24 months. In 24 eyes (26.7%) TDLC was the primary surgical treatment. Mean energy was 80 J (60-92 J). Success was defined as a final intraocular pressure (IOP) between 4 and 18 mmHg, a minimum IOP reduction of 20% and the absence of major complications. Results: The overall success rate was 36.7% after 24 months. A mean of 1.3 procedures was performed per patient. No correlation between age and success rate (p=0.887) or gender and success rate (p=0.895) was seen. There was no significant reduction in antiglaucomatous medication (p=0.208), no significant loss of visual acuity (p=0.324) nor a significant relationship between loss of visual acuity and failure of treatment (p=0.201). In patients with primary open-angle glaucoma the success rate was 40.9% after 24 months; in patients with pseudoexfoliative glaucoma it was 25.0% after 24 months. There was no significant difference between primary open-angle glaucoma and pseudoexfoliative glaucoma (p=0.684). Previous ocular surgery decreased the success probability from 45.8 to 33.3% (p=0.001). Prolonged hypotonia occurred in 1 patient. No phthisis bulbi developed. Conclusions: Transscleral diode laser cyclophotocoagulation is an effective and safe method not only in the treatment of refractive glaucoma, but also as a primary surgical procedure in primary open-angle and pseudoexfoliative glaucoma. TDLC may be used more widely in glaucoma therapy, although further long-term studies have to confirm these findings.