Abstract
Purpose: :
Neovascular glaucoma (NVG) is a devastating disease that is difficult to control. Transscleral diode cyclophotocoagulation (TSDCPC) is a known effective treatment modality to lower intraocular pressure (IOP) in NVG. The purpose of this study is to compare the efficacy of IOP reduction by TSDCPC in NVG caused by retinal vein occlusions (RVO) versus proliferative diabetic retinopathy (PDR).
Methods: :
47 eyes of 47 patients with NVG who received TSDCPC were retrospectively reviewed. 18 eyes had NVG from RVO and 29 from PDR. Success was defined as IOP > 4 mm Hg and < 21 mm Hg. Comparison of TSDCPC settings, pre and post operative IOP and number of medications between groups were analyzed.
Results: :
Mean age was 61 and 59 years in the RVO and PDR groups, respectively. The total fluence used was 80 Watts in the RVO group and 88 Watts in the PDR group. The preoperative IOP was 48+/-20 mm Hg and 47+/-21 mm Hg for the RVO and PDR groups, respectively (P=0.53, CI -6.1 to 8.6, unpaired t-test). Postoperative IOP at 1, 3 and 6 month intervals for the RVO group was 21+/-20, 21+/-15, 27+/-29 mm Hg and for the PDR group, 17+/-51, 19+/-55 and 20+/-53 mm Hg at 1, 3 and 6 months, respectively (P=0.17, CI -3.2 to 17.7, unpaired t-test). Success at 6 months was 50% for RVO and 65% for PDR. Mean number of ocular hypotensive medications decreased from 4 to 2 in both groups (P<0.001, paired t-test). 11% and 21% of the RVO and PDR groups, respectively, underwent TSDCPC therapy a second time within the 6 month period. There were no complications after TSDCPC in either group.
Conclusions: :
TSDCPC is safe and effective in lowering IOP in patients with NVG from both RVO and PDR. Although the differences in IOP at 6 months between the two groups was not statistically significant (P=0.17) the PDR group showed a higher success rate compared to the RVO group. TSDCPC settings and the decrease in number of ocular hypotensive medications used were similar in both groups.
Keywords: neovascularization • laser • intraocular pressure