Endoscopic Cyclophotocoagulation (ECP)

Glaucoma Treatments for Dogs & Cats in Fishers, IN

Glaucoma is a painful and blinding disease that is caused by increased pressure within the eye, which our Ophthalmologists at VCA Advanced Veterinary Care can help with.

This increased intraocular pressure (IOP) can exert damaging forces on the retina and optic nerve, the very sensitive layers at the back of the eye. The retina is responsible for changing an incoming light stimulus into an electrical signal, while the optic nerve, an extension of the brain, carries that signal to the brain to be interpreted as vision. In glaucoma, there can be significant damage to the retina and optic nerve, impeding the visual signal from reaching the brain, leading to blindness. Other clinical signs commonly seen with glaucoma include: redness, cloudiness, enlargement of the eye, lethargy, and/or inappetence.

Primary vs. Secondary Glaucoma

Glaucoma can be primary or secondary. Primary glaucoma is a genetic condition where the drainage of the eye is formed inappropriately. Common primary glaucoma breeds are: American Cocker Spaniel, Boston Terrier, Beagle, Bassett Hound, Shar Pei, Chow Chow, Siberian Husky, Shiba Inu, and Bouvier des Flandres.

Secondary glaucoma occurs when something is blocking the flow of fluid within the eye. Common causes of secondary glaucoma include: intraocular inflammation, tumors, lens luxation, and trauma.

Acute glaucoma is an emergency. If the IOP remains elevated for more than 48-72 hours, permanent vision loss can occur. Unfortunately, this disease is progressive and there is no cure. However, there are ways to treat glaucoma that can delay loss of vision or slow the onset of high pressure within the eye.

Medical and Surgical Management of Glaucoma

There are various treatment options depending on the main goal for the patient: comfort and vision.

Anti-glaucoma medications

These medications are used to lower IOP, reduce pain, and delay future IOP spikes that can lead to blindness. There are various medications that work through different mechanisms, both by lowering fluid production within the eye and also increasing fluid outflow from the eye. Unfortunately, all patients eventually fail medical management and will require surgery to either maintain vision or relieve discomfort after vision loss.

Surgical options to maintain vision

• Diode laser cyclophotocoagulation: This involves placing a diode laser against the scleral shell of the eye to deliver energy to the ciliary body. The ciliary body is subsequently destroyed. This is important to reduce fluid production, and therefore IOP, as the ciliary body is responsible for making the fluid within the eye.

• Goniovalve/gonioshunt: This involves placing a permanent drain against the scleral shell of the eye and inserting tubing into the eye to allow for consistent fluid drainage to lower IOP.

• Endoscopic laser cyclophotocoagulation (ECP): ECP requires highly specialized equipment to decrease the pressure within the eye. An ophthalmic endoscope is inserted into the eye, and a diode laser is used to destroy the ciliary body, which decreases the fluid production within the eye.

Surgical options to provide comfort (not maintain vision)

• Enucleation (eye removal): This is an end-stage procedure used in cases of uncontrolled glaucoma in blind and painful eyes. This requires the removal of the eye. The eyelids are carefully sutured together following the eye removal.

• Ciliary body ablation: This is an end-stage procedure used in cases of uncontrolled glaucoma in blind and painful eyes. It requires injecting an antibiotic, gentamicin, into the back of the eye. This works by destroying the ciliary body, reducing fluid production. However, unlike the laser procedures, this will cause permanent blindness and is only used in cases where vision is no longer present.