There are several surgical options for glaucoma treatment in cats. Surgical options depend on the specific cause of the glaucoma, severity of the condition, and preferred outcome. In order to be well-informed regarding a decision for glaucoma surgery, many points must be considered. Surgical options aim to either reduce pressure within the eye, reduce the amount of fluid that the eye produces, increase fluid drainage, or relieve the pain your cat is experiencing.
Causes of Glaucoma
Glaucoma in cats is caused when an increased pressure builds up behind the eye. Cells inside the eye normally produce a fluid called "aqueous humor" which nourishes and maintains the eye. Drainage of this fluid is important to keep a proper balance in maintaining eye pressure. When the drainage system becomes clogged, while the eye is still producing fluid at a normal rate, pressure builds, causing it to stretch or enlarge. This can cause damage to the optic nerve, decrease of blood flow to the retina and severe pain. Glaucoma can potentially lead to permanent blindness. In cats, glaucoma is usually secondary to an underlying condition. The most common condition leading to glaucoma in cats is uveitis, or inflammation inside the eye.
Increasing Fluid Drainage
It seems the logical choice for treating glaucoma in cats would be to increase the drainage of excess fluid by repairing or unclogging the affected area. Unfortunately, due to the delicate structure of the eye, this process is challenging and complex. A higher rate of success can normally be obtained by slowing the rate of fluid produced in the eye, rather than attempting to repair or bypass drainage clogs.
Reducing Fluid Manufacture
The pressure that causes glaucoma in cats can be relieved by reducing or slowing the rate of fluid production. In order to accomplish this, the cells in the front section of the eye must be surgically destroyed. Freezing the cells with cryotherapy, or killing them with laser surgery are the two methods most commonly used. Keep in mind that these types of surgeries are also complicated and expensive for cats. Additionally, home care and therapy must be maintained to keep the eye healthy after surgery. This procedure will likely need to be repeated every 9 to 18 months.
Surgical Eye Removal
If vision is completely lost, pain is severe, or chances for chronic eye problems are high, surgical removal of the eye called enucleation, may be the best option. The quickest and least expensive method includes removal of the eye and suture of the eyelids shut. If you prefer to maintain structure of the eye for cosmetic reasons, a prosthetic ball can be inserted. The prosthetic does not cause pain to the cat, and while no vision will be possible, the eye will still be able to move and blink. Enucleation is a permanent solution. After surgical removal of the eye, the glaucoma is cured and no additional treatment or therapy should be required.