Endocyclophotocoagulation (ECP) is a surgical technique employed in ophthalmology to address specific eye conditions. This minimally invasive laser procedure targets the internal structures of the eye. Its primary aim is to regulate the pressure within the eye, thereby supporting ocular health and preserving vision.
Understanding Endocyclophotocoagulation
Endocyclophotocoagulation (ECP) is a procedure designed to reduce intraocular pressure (IOP) by decreasing the production of aqueous humor, the fluid that fills the front part of the eye. The ciliary body, located behind the iris, is responsible for producing this clear fluid. When the ciliary body produces too much aqueous humor or the eye’s drainage system is inefficient, IOP can rise.
The procedure utilizes a specialized endoscope, a tiny device with a camera, light, and a laser, inserted into the eye. This allows the surgeon to visualize the ciliary processes. Laser energy is applied to these processes, causing them to shrink and reduce their fluid-producing capacity. This ablation of the ciliary epithelium leads to a decrease in aqueous humor formation, effectively lowering eye pressure.
ECP stands apart from other laser treatments that focus on improving fluid outflow by directly suppressing aqueous production. Direct visualization allows for targeted treatment of the ciliary processes, leading to more predictable outcomes and less collateral tissue damage compared to older methods. This internal, minimally invasive approach makes ECP a refined option for managing eye pressure.
Conditions It Addresses
Endocyclophotocoagulation is primarily a treatment option for various forms of glaucoma, eye conditions characterized by damage to the optic nerve, often linked to elevated intraocular pressure (IOP). Reducing IOP is important to prevent further damage to the optic nerve and preserve vision.
ECP is considered for primary open-angle glaucoma and refractory glaucoma, particularly when other treatments have not achieved sufficient pressure control or are unsuitable. It can also be applied in cases of angle-closure glaucoma, pigmentary glaucoma, neovascular glaucoma, and pediatric glaucoma. It may benefit patients with plateau iris syndrome by causing the ciliary processes to shrink, which can help open the anterior chamber angle.
While traditional cyclophotocoagulation was often reserved for advanced glaucoma, ECP’s improved precision allows for its use earlier for patients with mild to moderate glaucoma. However, conditions like uveitic glaucoma might present a higher risk of inflammation, and very high IOP (above 40 mm Hg) may lead to consideration of other surgical approaches like trabeculectomy or tube shunts.
What Happens During the Procedure
Before the endocyclophotocoagulation procedure, a local anesthetic is administered to numb the eye, ensuring patient comfort. Patients usually remain awake during the procedure. In some cases, a sedative medication may also be given.
A small incision (between 1.5 to 2.2 mm) is made in the cornea or sclera. A specialized probe (often 20-gauge) is inserted into the eye through this incision. This probe contains a light source, a video camera, and a diode laser, allowing the surgeon to see the internal structures on a monitor.
The surgeon uses the endoscope to visualize the ciliary processes behind the iris. A cohesive viscoelastic agent is injected to expand the ciliary sulcus, creating more space for the probe and improving visualization. Laser energy, typically an 810 nm wavelength diode laser, is applied to the ciliary processes. The goal is to achieve visible whitening and shrinkage of the tissue, indicating a reduction in aqueous humor production.
The laser is applied precisely, usually treating approximately 270 to 360 degrees of the ciliary processes. The procedure is often performed in conjunction with cataract surgery, where ECP is completed after the cataract removal and before the intraocular lens is inserted. The ECP procedure typically lasts 5 to 15 minutes, though the total time in the operating room, including any combined procedures, may be longer, up to two hours.
After the Procedure
Immediately after the procedure, patients may experience mild discomfort, and their vision might be blurry. An eye patch is placed over the treated eye for 24 hours. Patients are discharged on the same day but will need someone to drive them home due to the sedatives and anesthetic used.
Post-operative care involves prescribed eye drops, including topical antibiotics, anti-inflammatory drops (like corticosteroids), and sometimes non-steroidal anti-inflammatory medications. These drops reduce inflammation and prevent infection. A plastic shield at night for about one week is recommended to protect the eye, and sunglasses should be worn during the day outdoors.
Patients are advised to avoid strenuous activities, heavy lifting, bending, rubbing the eye, eye makeup, and swimming for one to two weeks. While vision may initially be worse, it typically improves over one to two weeks, though full stabilization can take several weeks to months. Follow-up appointments are scheduled at one day, one week, and one month after the procedure, to monitor intraocular pressure and assess healing.
The primary outcome is a reduction in intraocular pressure, with full effect observed in about 6 to 8 weeks. Many patients may reduce or even discontinue glaucoma medications over time. Common, temporary side effects include inflammation, light sensitivity, and dryness or watering. Less common side effects include temporary spikes in eye pressure, fibrin exudation, or hyphema (bleeding in the eye).