While many glaucoma procedures are ideal for a specific subset of patients, endoscopic cyclophotocoagulation (ECP) has a truly bimodal distribution of patient applicability. The efficacy and low risk profile are useful both as an initial treatment as well as with severe refractory patients with few other options.
ECP AS INITIAL TREATMENT
ECP is an effective treatment for patients who need to significantly lower IOP as well as those who are looking to reduce or eliminate their dependence on topical ocular hypotensive medications. It can be performed as a standalone procedure or in combination with other microinvasive glaucoma surgeries, such as iStent Trabecular Micro-Bypass (Glaukos) implantation. Importantly, it does not eliminate any future surgical options for glaucoma; I can combine it with every other glaucoma therapy I use.
My only relative exclusion for ECP is that if the patient has his or her natural lens in the eye, the treatment might not be completed as thoroughly as desired. Thus, I find it to be an excellent fit with cataract surgery. Studies have shown that phacoemulsification combined with ECP reduces IOP by more than 20% while also reducing medication requirements by an average of one medication.1 ECP can be performed through the same clear cornea cataract incision, involves no sutures, and does not leave a hole in the eye. I tend to first perform phacoemulsification and remove the lens from the eye. Then I inject intracameral lidocaine followed by viscoelastic and perform ECP. I often create a second incision so that I can treat a full 360°; this is no more traumatic for the eye than a partial treatment of fewer degrees and is more effective at lowering IOP.
Postoperative care is very similar to cataract surgery alone, with the caveat that there is often slightly more or prolonged inflammation; therefore, patients must often use steroid or NSAID drops for a longer period of time. I find it effective to manage these patients with a dropless therapy, such as a transzonular injection of TriMoxi (Imprimis Pharmaceuticals). This leaves the eyes in excellent condition from day 1. In patients who do not undergo the dropless approach, I inject kenalog or decadron into the eye to ensure that patients receive the steroids needed to combat early inflammation.
ECP is perhaps even more effective in cases of refractory glaucoma, as eyes with higher IOP can experience large reductions in IOP after ECP. In patients with previous trabeculectomy or tube shunts who need additional therapy, a surgeon has the option to either repeat the previous procedure or select another one. I am not inclined to put multiple tube shunts in an eye, as that is a lot of hardware, and the subsequent shunts often do not work much better than the first one. Likewise, repeat trabeculectomies have a lower success rate than primary filtering procedures..
I have many refractory glaucoma patients referred to me, and I find that ECP has the ability to lower IOP quite a bit. A comparison of ECP to the Ahmed Glaucoma Valve showed that they were nearly equal in IOP-lowering ability, while patients treated with the Ahmed tube shunt had significantly more complications.2 Mean IOP in the ECP group decreased from 41.61 +3.42 mm Hg at baseline to 14.73 +6.44 mm Hg at 24 months.
For most of my refractory glaucoma patients, I perform ECP with a pars plana approach, which allows me to be thorough in treating the ciliary processes, as there are no anatomic structures such as zonules in the way of the treatment. For patients with prior retina surgery, cases of failed transscleral cyclophotocoagulation, aphakic eyes, or most other unusual and difficult circumstances, ECP is still an option. It is rare that I cannot find access for the ECP probe and complete the procedure.
ECP is a great procedure for glaucoma specialists as well as for cataract surgeons, who often provide the first glaucoma treatment for their patients. As long as one has a large enough glaucoma population to become confident with the procedure, it is an excellent option to combine with cataract surgery and reduce your patients’ medications or to use as a standalone therapy. However, there are a few important points to remember when performing ECP.
In my experience, physicians that commonly see a lack of efficacy are not treating as close to 360° of the ciliary processes as possible.
Inflammation must be treated proactively, not simply wished away.
Although patients experience varying degrees of inflammation, I find it best to inject a steroid into the eye at the conclusion of the procedure rather than waiting for inflammation to pop up.
Unlike procedures that leave a hole in the eye, IOP does not decrease immediately.
This creates the need to manage pressure spikes. I find it useful to manage my patients prophylactically in the postoperative period with ocular hypotensive medications until I see the effect of ECP kick in.
ECP is truly an effective and flexible procedure that all cataract surgeons and glaucoma specialists should have in their toolbox. Although it requires an incision, ECP is still minimally invasive and has an excellent safety profile. In addition, treating inside the eye avoids crossing the ciliary muscle vasculature and sclera, making it significantly more comfortable for patients.
1. Clement CI, Kampougeris G, Ahmed F, Cordeiro MF, Bloom PA. Combining phacoemulsification with endoscopic cyclophotocoagulation to manage cataract and glaucoma. Clin Experiment Ophthalmol. 2013;41:546-551.
2. Lima FE, MAgacho L, Carvalho DM, Susanna R, Avila MP. A prospective, comparative study between endoscopic cyclophotocoagulation and the Ahmed drainage implant in refractory glaucoma. J Glaucoma. 2004;13(4):233-237.