ECP in refractory glaucoma yields versatility, favorable safety profile with positive results

Take-home message: Endoscopic cyclophotocoagulation with vitrectomy and pars plana treatment is effective in reducing IOP in patients with ultra-refractory glaucoma, reducing the need for medications and being relatively well tolerated by patients.

By Brian A. Francis, MD, Special to Ophthalmology Times

Los Angeles-When it comes to glaucoma that is refractory to multiple aqueous shunts and maximal medical therapy, there is no consensus on its treatment.

Additional tube shunts present risks of strabismus and tube or plate exposure and discomfort.¹ Inflammation, hypotony, and phthisis are all complications associated with transscleral cyclophotocoagulation and cyclocryotherapy.^2,3

I have found success with endoscopic cyclophotocoagulation (ECP) and a procedure, which is ECP with vitrectomy and pars plana treatment (ECP Plus).

ECP is unique among surgical glaucoma therapies in that it addresses aqueous production rather than aqueous outflow. This gives it the advantage of being effective as a stand-alone procedure or in conjunction with any other procedure that addresses aqueous outflow.

In addition, ECP is versatile enough to treat open-angle and chronic angle-closure glaucoma, as well as every stage of disease.

In standard anterior ECP, the anterior ciliary processes are photocoagulated via a clear corneal approach. To get the maximum effect, I recommend treating each process, as much of the process as possible, and in between each process. This should be performed for a complete 360°. Laser power should be titrated so that each process is visibly whitening and shrinking, but not popping.

Study results

My colleagues and I previously published the results of a prospective, nonrandomized, interventional clinical trial of 25 eyes of 25 consecutive glaucoma patients with uncontrolled IOP despite a functional tube shunt and maximum medical therapy.⁴

ECP was performed on all patients applying 250 to 350 mW of laser to each ciliary process visible for 360°, as well as the intervening spaces between the processes.

Patients were followed for 24 months, and a mean preoperative IOP of 24 mm Hg was reduced to a mean IOP of 18.1 mm Hg at 24 months (–7.0 or 25.5%).

Results also included a statistically significant decrease in mean medications of 1.45 (p < 0.01). With no serious complications, researchers concluded that ECP has a role in glaucoma management after tube shunts.

While the results of ECP in refractory glaucoma are good, we continue to search for a greater magnitude and duration of IOP reduction for the most severe glaucoma patients. In comparison with standard anterior ECP, pars plana ECP Plus allows for a more complete treatment of the ciliary processes, and ECP Plus includes treatment of the pars plana in addition to the ciliary processes.

Pars plana ECP can be performed though a standard three-port vitrectomy, or can be done through a two-port vitrectomy if an anterior chamber maintainer is used. A pars plana incision is generally made with a 19 to 20 gauge MVR blade or a 2.2-mm keratome. The vitrector is placed in one port and the endoscope in the other, so that a limited vitrectomy is performed followed by ECP on one side. The surgeon then switches hands to treat the other side. This approach works quite well for anterior segment surgeons.

In ECP Plus, a pars plana approach is used but the treatment area includes all of the ciliary processes as well as about 1 to 2 mm of pars plana. Typically with a pars plana approach, and certainly when we are treating the pars plana as well, we may want to avoid treating the entire 360° because you are treating much more of the ciliary epithelium due to improved access to the entire length of the ciliary processes.

We conducted a retrospective analysis of 53 consecutive patients with uncontrolled IOP despite prior glaucoma surgeries and maximally tolerated medical therapy that underwent ECP Plus.⁵

Mean preoperative IOP of 27.9 +/-7.5 mm Hg was lowered to 10.7 +/-5.2 mm Hg at 12 months. Mean number of medications was reduced from 3.4 +/-1.2 pre-treatment to 0.7 +/-1.2 at 12 months postoperative. Complications in the early postoperative period included hyptony (3/53; 5.7%), choroidal detachment (4/53; 7.5%), cystoid macular edema (4/53; 7.5%), uveitis with anterior chamber fibrin (2/53; 3.8%) and hyphema (2/53 (3.8%). All cases of uveitis and hyphema were resolved prior to 3 months postoperative.

Late postoperative complications included hypotony, choroidal detachment, CME unrelated to hypotony, and failed corneal graft-all in low enough rates of incidence to be acceptable given the nature of the disease being treated.

ECP Plus is effective in reducing IOP in patients with ultra-refractory glaucoma, reducing the need for medications and being relatively well tolerated by patients. However, caution must be exercised in patients with compromised ciliary bodies, such as with uveitis and neovascular glaucoma.

The versatility of ECP, the combination of a favorable safety profile, and positive results, make it an excellent tool for every surgeon who treats glaucoma.

In addition, the endoscopic viewing system has multiple other potential applications for both anterior and posterior segment surgery.

Brian A. Francis, MD

E: BFrancis@Doheny.org

Dr. Francis is professor of ophthalmology, Doheny Eye Institute, David Geffen School of Medicine, University of California, Los Angeles. Dr. Francis is a paid consultant for BVI/Endo Optiks.

References

• Sidoti PA. Inferonasal placement of aqueous shunts. J Glaucoma. 2004;13:520–523.

• Lin S. Endoscopic cyclophotocoagulation. Br J Ophthalmol. 2002;86:1434–1438.

• Shields MB, Shields SE. Noncontact transscleral Nd:YAG cyclophotocoagulation: a long-term follow-up of 500 patients. Trans Am Ophthalmol Soc. 1994;92:271–287.

• Francis BA, Kawji AS, Vo NT, Dustin L, Chopra V. Endoscopic Cyclophotocoagulation (ECP) in the Management of Uncontrolled Glaucoma With Prior Aqueous Tube Shunt. Journal of Glaucoma. 2010.

• Tan JC, Francis BA, Noecker R, Uram M, Vakili G, Dustin L, Chopra V. Endoscopic cyclophotocoagulation and pars plana ablation (ECP-plus) to treat refractory glaucoma. J Glaucoma. 2015 May 14 Epub ahead of print.