Enucleation (removal of eye)
WHY MIGHT THIS PROCEDURE COME TO BE NECESSARY?
In almost all cases, the eye is removed because it has reached
a point where it has no chance of being capable of sight and it
is painful. Trauma to the eye (such as a scratch to the eye that
becomes infected, hitting the eye on something sharp), tumors
of the eye, glaucoma (increased pressure inside the eye), and
Herpes infection related ulcers on the eye (in cats) are all catastrophes
to the eye. Any of these conditions, or others create a painful
blinded eye. Brachycephalic breeds (those with flattened faces
and prominent eyes) tend to be predisposed to eye injuries and
often it is these breeds that end up with one eye enucleated.
The focus must become the relief of pain when restoring vision
becomes hopeless.
ARE THERE ANY ALTERNATIVES TO ENUCLEATION?
Most people have a strong preference for their pets to have two
eyes and would like to keep both their pet’s eyes if possible.
Frequently, this is indeed possible with the help of a board certified
ophthalmologist. Many eye wounds can be trimmed and closed with
proper magnification and especially tiny suture. Sometimes the
inner contents of the eye can be removed and replaced with a prosthesis.
(This is called “evisceration” and the prosthesis is
called a “black ball.”) This creates a more natural
looking “eye” but is not appropriate for infected eyes
or eyes with tumors. There are also advanced procedures that can
resolve glaucoma surgically and still spare the eye.
All of the above are highly specialized procedures that can only be performed by an ophthalmologist. Often enucleation is selected as the other procedures are too expensive (they often cost 3 or 4 times as much as enucleation) or enucleation may simply be the best choice.
IS THE SURGERY PAINFUL OR DISFIGURING?
It is not painful after the initial post-surgical recovery, but
during recovery the surgical area is quite sore. The pain resolves
quickly over the first few days after surgery. Often we will use
a special skin patch, called a Fentanyl Patch , to deliver pain
medication during this initial period.
WHAT CAN WE EXPECT AFTER THE SURGERY?
In surgery, the eye is removed and the eyelids are sewn closed.
Sometimes there are stitches to be removed in 10-14 days and sometimes the stitches are buried inside the eye socket. The eyelids will be swollen and there may be some bruising. (If the eye injury is more recent, there tends to be more swelling and bruising than if the injury is more chronic.) Some red-tinged fluid may seep from the incision and this is normal. The eye may at first look like it is simply closed. Over the first week following surgery, the swelling will go down and the socket will flatten out.
An Elizabethan collar is often provided to discourage rubbing or scratching of the eye. This collar should stay in place for 10-14 days until the incision is healed. The pet should be able to eat and drink with the collar in place but if you are concerned, you may remove the collar at meal time provided the pet is well supervised.
The pet will have lost peripheral vision on the side of the enucleation and may need to adjust to being approached from this side. Cats should be kept as indoor only pets after an enucleation as the outdoor lifestyle will pose even more hazard than usual.
WHAT SIGNS WOULD INDICATE A PROBLEM?
Infection may pose a complication. In this even, the eye area
would remain swollen after the initial week and the incision may
drain pus. If this occurs, the infection would require drainage
and antibiotics. If you think there may be infection present,
recheck with your vet as soon as possible. Remember, some mild
oozing of red-tinged fluid is normal during the first few days
after surgery.
If the eye was enucleated due to a severe tear or rupture, the eye may not be removed in one piece. Sometimes a small fragment of the rear eye membranes remains behind. If enough of this tissue is present, secretion of fluid can continue and chronic oozing from the incision can be a problem. If this is excessive, the eye socket may require a second surgery to be fully cleaned out.
Both these complications are very rare.
WHAT LIMITATIONS WILL THE PET HAVE?
As long as the other eye is visual, there are not likely to be
any serious handicaps. The pet will not be able to see on the
enucleation side and may bump into objects there. The pet may
be easily startled when approached from that side. Otherwise,
once healing is complete, life can return to normal. If your pet
has a condition that endangers the remaining eye, be sure you
understand any preventive measures that should be taken.
Further questions on this procedure should be directed to your veterinarian.