Appreciating the ECP Advantage
Here's how endoscopic technology brings precision to surgical glaucoma therapy.

The most challenging aspect of treating glaucoma is ensuring patients' compliance with medical therapy. We know the IOP-lowering eye drops prevent disease progression, but from the patient's perspective, instilling one or more medicines every day can be a nuisance.

Surgical treatments, such as trabeculectomy, trabeculoplasty and iridectomy sometimes decrease a patient's dependence on medical therapy, but these procedures can cause scarring, bleb formation or other detrimental changes in ocular anatomy.

Ongoing research suggests that endoscopic cyclophotocoagulation (ECP) effectively lowers IOP without causing the complications associated with other surgical glaucoma treatments. Instead of redirecting excessive fluid, ECP reduces aqueous fluid production, lowering IOP and preventing progressive optic nerve degeneration.

This article provides a brief overview of this procedure as well as the reasons why I've adopted it.

During ECP, we insert a special probe containing a light source, an endoscopic camera and a diode laser into the patient's eye.

What is ECP?

During ECP, we insert a special probe containing a light source, an endoscopic camera and a diode laser into the patient's eye through a clear corneal or limbal incision. Using the camera, we can visualize and then direct laser energy at the ciliary body, effectively decreasing the ciliary epithelium's ability to produce aqueous humor.

The technical difficulty of ECP varies, depending on whether the patient is phakic, aphakic or pseudophakic. In my experience, the easiest patients to treat are the fresh pseudophakes. Typically, these patients have few adhesions and intact ocular anatomy. Once I place the IOL, I add more vicoelastic and use a curved probe to ablate up to 360° of the ciliary body. (To learn the advantages of curved versus straight probes, see "Tips on Tips.")

Phakic patients are the most challenging to treat with ECP, as the bulk and curvature of the intact natural lens can make it difficult to get a clear view of the ciliary body.

Although ECP can be executed by the pars plana approach, as an anterior segment surgeon, I'm more comfortable using the clear cornea approach. After administering anesthesia, I make my incisions (two if I'm using a straight probe, one for a curved probe) and insert the microendoscope into the patient's eye. Once I can see the ciliary body on the monitor, I begin treating the tissue, applying energy until the ciliary processes turn white.

The procedure doesn't take long, sometimes as little as 2 minutes, depending on the surgeon's skill level. Nevertheless, these 2 minutes can have a significant effect on a patient's post-op IOP.

What Can Patients Expect?

In general, ECP patients follow the same post-op protocol as cataract patients, including topical steroids and non-steroidal anti-inflammatory agents to prevent inflammation and topical antibiotics to prevent infection.

I instruct patients to continue their glaucoma medications until I determine they're no longer needed. Patients' IOPs tend to slowly decrease and fluctuate for the first 2 post-op weeks, but usually they stabilize between the second and eighth post-op week, at which time I can consider retreatment if I'm not satisfied with the outcome.

Who Benefits From ECP?

Among all my glaucoma patients, I prefer ECP for those with:

• Aphakia or prior vitrectomy
• Corneal transplants
• Congenital glaucoma
• Replacement medical therapy (in conjunction with other surgery, such as phacoemulsification)
• Medication failures (side effects, lack of efficacy, economic failure)
• Previously unsuccessful transscleral cyclophotocoagulation (TCP).

Treating aphakic glaucoma with ECP allows me to lower IOP while maintaining a closed system post-op, thus reducing the risk of suprachoroidal hemorrhage. Also, intraoperatively, continuous infusion of BSS helps reduce hypotony during the procedure.

When treating corneal transplant patients with ECP, I can lower their IOPs without sorting through anatomy altered by multiple anterior segment surgeries.

Congenital glaucomas are easily treated with ECP because I can visualize and treat the ciliary processes, effectively lowering IOP without damaging collateral structures. Some of the failures with TCP come from the abnormal location of the ciliary body relative to the limbus.

Seton placement is an IOP-lowering option I usually reserve for patients with scarred conjunctiva but reasonable visual potential. However, the presence of this permanent device causes gradual epithelial cell loss even in the best of circumstances, as well as the risk of diplopia and hypotony.

As clinicians, we're using ECP to treat more and more glaucoma patients. We're using this technology to replace or reduce medical therapy and to avoid trabeculectomies and setons in difficult-to-treat patients, such as those we are concerned may be noncompliant with post-op therapy and follow-up. Most importantly, we can use ECP to help patients whose treatment options are diminishing.

Finally, ECP is rapidly replacing TCP as the preferred therapy for neovascular and intractable glaucomas. If a patient has reasonable vision, I'll definitely choose ECP over TCP to lower that patient's IOP. Furthermore, it's easier to titrate the degree of treatment, given the narrow therapeutic window that some of these patients have.

Improving Glaucoma Compliance

ECP is an efficacious adjunct to medical therapy. If my patients are scheduled for any surgical procedure, I often take the opportunity to administer ECP to either decrease their dependence on medical therapy or in some cases, to eliminate the need for IOP-lowering eye drops.

In this age of better medical and laser therapies for glaucoma, ECP can help us improve patient compliance by reducing their need for medications without risking the vision loss that's inevitable with untreated glaucoma.

Dr. Noecker is vice chair of the department of ophthalmology at the University of Pittsburgh. He's also director of the glaucoma service.