Visual Loss After Transscleral Diode Laser Cyclophotocoagulation for Primary Open-angle and Neovascular Glaucoma

Background And Objective: Varying incidences of visual loss after transscleral diode laser cyclophotocoagulation for uncontrolled intraocular pressure (IOP) have been reported. This study compared the treatment response in primary open-angle (POAG) and neovascular (NVG) glaucoma, particularly regarding vision loss.

Patients And Methods: Case notes of consecutive patients who underwent transscleral diode laser cyclophotocoagulation between March 2001 and September 2005 were retrospectively reviewed. A diagnosis of POAG or NVG and at least 6 months of follow-up were required for inclusion. Conservative laser parameters were used. The treatment response of the POAG and NVG groups was compared.

Results: Twenty-five eyes of23 patients with POAG and 14 eyes of 14 patients with NVG were studied. Mean follow-up was 22.4 and 12.9 months in the POAG and NVG groups, respectively. Post-treatment, both groups had significant reduction in mean IOP of 7.3 (29.2%) and 13.2 (36.6%) mm Hg, respectively (between group P = .18). One eye in each group had mild hypotony of 4 mm Hg, and no eyes became phthisical. Oral acetazolamide treatment was significantly reduced in both groups. Visual acuity post-treatment decreased in both groups; the POAG eyes had better initial visual acuity and lost more visual acuity. Nine of 25 (36%) POAG and 4 of 8 (50%) NVG eyes lost 2 or more LogMAR lines.

Conclusions: Transscleral diode laser cyclophotocoagulation reduced IOP and medication requirements in POAG and NVG. Patients should be warned that visual loss may occur, especially in endstage glaucoma.