Refractory glaucoma treated with endolaser cyclophotocoagulation during pars plana vitrectomy

Abstract

Purpose : Endolaser cyclophotocoagulation (ECP) is invasive, but necessary for treating uncontrolled intraocular pressure (IOP) in glaucoma. However, it is not common, and few studies have reported the use of ECP in vitreoretinal surgery. This report describes recent cases of ECP during vitreoretinal surgery.

Methods : This study included 11 eyes of 11 secondary glaucoma patients with poorly controlled IOP, who were treated at the Tohoku University Department of Ophthalmology (age: 48.2 ± 16.5 years, male/female ratio: 7/4). All 11 eyes underwent microincision vitrectomy surgery as a primary treatment, then underwent ECP of the pars plicata and/or pars plana for secondary glaucoma. The number of laser shots was counted retrospectively in a video of the operation. Visual acuity (VA), IOP, and the number of glaucoma medications were collected before and for 6 months after ECP. Successful IOP control was defined as IOP at or below 21 mmHg throughout the follow-up period.

Results : The study included 11 eyes with secondary glaucoma (10 eyes with neovascular glaucoma and one eye with post-operative glaucoma). Primary causes of neovascular glaucoma included proliferative diabetic retinopathy, radiation retinopathy, ocular ischemic syndrome, and central vein occlusion. Six eyes underwent combined pars plicata and pars plana ECP, of which 4 (66.7%) had successful IOP control after 6 months. Five eyes underwent pars plana (without pars plicata) ECP, of which 4 (80.0%) had successful IOP control after 6 months. Thus, success was achieved in 8 eyes, while 3 eyes needed additional operations due to persistent IOP over 35 mmHg. Changes in IOP over time are shown in Tables 1 and 2. Compared with the mean preoperative IOP of 46.5 ± 12.0 mmHg, there was a significant IOP reduction after ECP treatment at 1, 3 and 6 months (15.7 ± 6.3 mmHg, p<0.01, 15.5 ± 7.0 mmHg, p<0.01, 16.1 ± 6.3 mmHg respectively, p<0.01; paired t test with Bonferroni correction). There were no differences between patients who underwent only pars plana ECP and combined pars plicata and pars plana ECP in IOP reduction after 6 months (t test, p=0.423). Preoperative VA was maintained in all eyes, and severe adverse events were not observed in any patients.

Conclusions : ECP of the pars plicata and/or pars plana for lowering high IOP caused by refractory secondary glaucoma is an effective adjunctive procedure in vitreous surgery.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.