Prospective multicenter study underscores favorable safety profile for ECP

January 15, 2008

The safety of endoscopic cyclophotocoagulation for the treatment of glaucoma is being investigated prospectively in a multicenter study.

Key Points

Dr. Weston and co-investigators at five other centers have been collecting data prospectively to define the safety profile of ECP in treating glaucoma. A recent analysis was performed that included 5,824 patients representing a spectrum of glaucoma types with follow-up ranging from 1 to 13 years (mean, 5.2 years). The largest categories were composed of eyes with refractory glaucoma (2,641 eyes) and those with medically controlled glaucoma undergoing combination phacoemulsification and ECP (2,193 eyes). In addition, 605 eyes had neovascular glaucoma, 323 phakic eyes had with open-angle or pseudoexfoliation glaucoma, and 57 eyes had post-penetrating keratoplasty.

Results

"The excellent safety profile demonstrated by ECP over the short and long term in this large, diverse series supports the message that ECP is a different operation from historically used cyclodestructive procedures, with a safety profile far surpassing that of transcleral cyclophotocoagulation and comparing favorably with, if not superior to, trabeculectomy and tube implantation," said Dr. Weston.

"Transcleral cyclodestructive procedures result in a high incidence of complications because they cause full-thickness destruction of the ciliary body," he said. "However, ECP selectively targets the ciliary epithelium only, and, as our results show, it is a generally mild procedure."

Possible complications

In the study, the most common early complication was IOP spike (14.5%). Events occurred most often in eyes undergoing cataract surgery and generally were transient.

"A significant number of IOP spikes will be reported in any series of eyes undergoing cataract surgery due to incomplete viscoelastic removal. This can also occur with stand-alone ECP procedures," Dr. Weston said. "So many of these events in our series were not necessarily related to the ECP procedure itself."

Hyphema or vitreous hemorrhage was the second most common early complication (3.8%). Dr. Weston noted that limited bleeding is not unexpected considering the treatment is being applied to a vascular area. No serious bleeding or long-term sequelae from these events was seen, however, except in high-risk eyes.

In the early postoperative period, both serous choroidal effusion and IOL displacement occurred at a rate of 0.36%.

"Irritation of the choroid leading to effusion can occur if the ciliary body is treated a little too aggressively, but there were no significant consequences in our series. IOL displacement is a risk because the zonules can tear if the eye is overinflated in pseudophakic eyes due to rigidity of the zonule-capsule structures. However, these events were uncommon and can be avoided if the surgeon takes extra caution," Dr. Weston said.

During long-term follow-up, cataract developed in 261 (24.5%) of 1,066 phakic eyes.

No analyses were undertaken to determine whether cataract might have developed even without ECP, but intraocular manipulation of any sort may accelerate cataract progression, noted Dr. Weston.

"For this reason, it is suggested that only very experienced ECP surgeons attempt treating phakic eyes," he told Ophthalmology Times.

Serious complications included cystoid macular edema with visual loss (1.03%) and retinal detachment (0.27%). Dr. Weston noted that the rates of both of these complications were the same or better than those reported in series with comparable populations.