Enucleation in Dogs

Enucleation is the surgical removal of an eye and its associated structures, e.g. eyelids. The procedure is undertaken in order to prevent pain or spread of disease, such as when an eye is irreversibly damaged, cancerous, or affected by non-responsive glaucoma.

Enucleation in dogs is often a treatment of last resort, when all previous attempts to salvage the eye have failed. The procedure is carried out under full general anesthetic and, although a major procedure, there is every chance of a successful outcome. This is not a specialist procedure and is commonly carried out at general vet practice. 

Enucleation is never undertaken lightly and only after all other treatment options have been explored. For example with glaucoma, referral to place a surgical stent (drain) in the eye may be an option.

Enucleation requires full general anesthetic and may involve an overnight stay after the surgery, for additional pain relief and monitoring. Elderly patients may require intravenous fluids during the surgery to reduce the risk of kidney complications and to maintain blood pressure and hydration.

The procedure involves: 

• Preparing the patient by withholding food overnight prior to the operation
• A pre-op check, possibly including screening blood tests
• A premedication injection and pain relief to prepare the dog for the anesthetic
• The dog may be put on intravenous fluids at this point
• The anesthetic is administered via a catheter in the front leg and maintained via gas delivered through a tube in the airway
• A vet tech monitors the dog's vital signs 
• Hair is carefully clipped from around the eye and face
• The skin is made sterile with surgical scrub
• The surgeon scrubs up, and then sutures the eyelids of the affected eye together
• The surgeon removes the eye by careful dissection, and any bleeding vessels clamped and tied off
• Skin is sutured over the empty socket
• The dog wakes from the anesthetic and must wear a cone to protect the surgical site
• The dog is discharged with pain relief and perhaps antibiotics
• The dog requires a post-op check at two to three days
• The sutures are removed 10 - 14 days later

Once the initial post-operative discomfort is over, enucleation is extremely effective at preventing ocular pain, without risk of relapse. Many owners who opt for surgery after a delay often notice their dog is happier than it has been in some time, now the long term low pain has gone. In many cases, the alternative to enucleation is long-term management of a condition, which can be difficult or even impossible to achieve. This may require visits to specialists for repeated anesthetics to repair damaged corneal tissue or regular visits to have the pressure within the eye measured. Medical management of severe eye conditions is rarely successful, which leaves the possibility that the dog is in constant low-grade pain, so treatment decisions are best made with the dog's long term welfare in mind.

It is essential the dog wears a cone until the sutures are removed.

For the first two to three days postoperatively, the dog may be quiet from the anesthetic and experiencing some discomfort. The pain can be managed with medications, which your vet will supply. 

Following a check-up at the two to three-day point, the dog has gentle lead exercise until the sutures are removed at the 10 - 14-day mark. 

Complications are rare, but include hemorrhage or wound breakdown. If the bleeding is severe, revisional surgery may be required or the clinician may opt to pack the socket and use pressure to prevent further blood loss. However, the vast majority of patients make a full and uneventful recovery. 

Once the sutures are removed no further aftercare is needed and the patient is signed off. 

The one-off cost of enucleation surgery must be balanced against repeated specialist visits, repeated anesthetics, and ongoing medication costs. At a general practice, the cost of enucleation surgery ranges from around $400 - $950 depending on the supportive care needed. 

Prescription eye drops for glaucoma cost around $15 -25 per bottle and may last around 2 - 3 weeks each. When a condition is managed medically the dog may need weekly visits initially and then three-monthly check-ups. The cost of these visits can be $25 - 50 for a regular vet, to $70 - $270 for a specialist veterinary ophthalmologist. 

There are many factors to consider with enucleation surgery. The procedure is permanent and irreversible, and the dog blind on that side afterward. However, many of the conditions for which enucleation is appropriate may have already resulted in loss of sight. The short-term discomfort of surgery is balanced against the long-term benefit of being pain-free. In addition, this surgical option can be cost effective as the results are permanent. The risks of surgery are low and relate to hemorrhage and any anesthetic risks for that individual patient. However, good surgical technique and pre-op screening minimizes both of these factors.

Many of the health conditions that result in enucleation being an appropriate option are not preventable. Conditions such as glaucoma are strongly linked to genetic conditions such as luxating lens or poor drainage angles from the eye. Breeds most commonly at risk include terriers, Basset Hounds, and American cocker spaniels.

Owners of these breeds should be vigilant for the earliest signs of discomfort in their dog to get the eyes checked. Early medical treatment stands a better chance of success than much later intervention. 

Other problems such as eyes popping out of sockets are linked to face shape. Flat-faced breeds such as pugs and pekes are at greatest risk. To avoid problems, the owner should avoid scruffing their dog (which pulls back the eyelids) and use a harness rather than a neck collar. 

Owners should be vigilant for signs of eye discomfort, such as blinking and squinting, closing the eye, rubbing, or an ocular discharge, and seek veterinary attention. Prompt treatment of ulcers on the cornea (surface of the eye) can stop them from perforating which could result in the loss of an eye.