Enucleation describes the surgical removal of one or both eyes. It may be performed in many different species, including rabbits.

Enucleation surgery ©Vetstream Ltd

Like other prey animals, rabbits have large and prominent eyes that are located laterally (on the side of the face) giving them a nearly 360-degree field of vision. Such a wide field of vision allows rabbits to detect potential dangers at the earliest opportunity, a crucial adaptation for a species heavily preyed upon in the wild. Keeping on the lookout for predators is critically important for rabbits and to help with this, they have adapted to keep their eyes open as much as possible including three eyelids, four tear glands, and a single tear duct (drainage) opening in the bottom lid. Not only can they sleep with their eyes open, but they also have special anatomical features that enable them to blink less frequently than other animals. Unlike humans who blink around 12 times a minute, rabbits can blink as little as once every 1-5 minutes. While the special anatomical traits of the rabbit’s eye reduce the need for frequent blinking, the lack of blinking can sometimes compromise healing if an eye condition develops. Like with most mammals, the tear glands around the rabbit’s eye produce abundant tears that have important functions to protect the eye and eyelids from drying out and becoming damaged by debris. Tears consist of water to provide moisture, along with oils that lubricate and prevent evaporation. They also include mucus to ensure even distribution of tears across the eye's surface. This mucus is enriched with antibodies and specific proteins that help fight infections. Additionally, tears deliver oxygen and nutrients to the surface of the eyes, which lack blood vessels. The tear duct in the bottom lid functions to drain excess tears from the eye down a tract that empties in the nose. The compact structure of the rabbit face (particularly in dwarf and lop-eared rabbits) means the tear duct can get blocked if the rabbit develops dental disease resulting in chronic watery eyes and inflamed skin under the eyes.

Rabbits are very good at masking pain and injury to avoid appearing vulnerable to predators so ocular (eye) problems can become serious before they are noticed. Ocular conditions can deteriorate very quickly and are almost always very painful, so urgent veterinary care is required if an ocular problem is detected. If the eye is in reasonably good condition, the veterinarian may initiate intensive treatment. However, even with the best efforts, the rabbit’s unique anatomical features in the eye can contribute to unsuccessful treatment and the condition may worsen. In some cases, an ocular condition may be so severe that the rabbit sustains permanent damage and loss of sight. As ocular conditions are so painful, often the most humane option is to surgically remove the globe of the eye (called enucleation) so that the rabbit can heal quickly with minimal pain.

Whilst enucleation may seem a drastic decision to make, it is often the only humane option. Enucleation is typically well tolerated by rabbits and can help provide them with an improved quality of life through reduction or elimination of ocular pain. Conditions which may require enucleation include:

• Intraocular tumors/abscesses: rabbits can develop tumors or abscesses in or behind the eye which may push the eye outward resulting in bulging of the eye/s out of the socket (exophthalmos). Your veterinarian may attempt medical treatment of the condition but if the treatment is unsuccessful, or if the damage is extensive or worsening, enucleation may be required.
• Glaucoma: glaucoma is a condition where there is an increase in intraocular pressure (the pressure within the eye). It can be congenital (a condition or trait present at birth due to genetic or non-genetic factors) or it can be secondary to other ocular diseases. The condition is often not responsive to treatment so if the eye/s is non-functional and extremely painful, enucleation is required.
• Severe ocular trauma with bleeding: if the rabbit has had a serious injury to the eye, the eye may be beyond repair so rapid enucleation is the most humane option.
• Uveitis/endophthalmitis: uveitis/endophthalmitis are inflammatory conditions of the internal eye structures. These conditions can be caused by injury or infection, for example Encephalitozoon cuniculi infection. These conditions can be very difficult to treat if the inflammation is causing pain and vison loss so enucleation may be the most humane option.
• Corneal ulcers: a small scratch from debris, or stray eyelashes can progress to a persistent unhealing ulcer on the surface of the eye. These are very painful and can require surgery and prolonged treatment with eye medications to fully heal and even then, scar tissue from the healed ulcer can impair vision. If the ulcer does not have a good prognosis for a full recovery, or if the rabbit’s pain is not able to be controlled, enucleation may be advised.

As enucleation is surgical removal of the eye, your rabbit will be admitted and placed under a full general anesthetic for the procedure. Prior to the surgery, your veterinary surgeon will mark the eye that needs to be removed. Once your rabbit is anesthetized, the area around the eye will be prepared to minimize contamination of the surgical site, this usually involves clipping some of the fur away from around the eye that is being removed, followed by cleaning the area with an antiseptic. The procedure involves surgically removing the rabbit’s eye and many of the associated structures, as well as the eyelids. The remaining skin is sutured (stitched) closed leaving a seamless closure over where the eye used to be.  When the skin heals a small scar may be visible. The final appearance depends on the type of procedure, but usually appears flattened, or slightly concave, with smooth skin where the eye used to be. After the procedure, your rabbit is likely to need to stay in hospital for continued care for at least one day afterwards. This will include keeping the rabbit warm, offering continued pain relief to make sure they are comfortable, medications to keep the gastrointestinal tract moving (prokinetics), syringe feeding if your rabbit is not eating, fluid therapy, and wound care to ensure minimal bleeding and swelling of the surgical area. When your veterinarian is satisfied that your rabbit has recovered well enough from the surgery, they will be discharged to continue their recovery in your care.

Your rabbit will come home with pain relief to be continued at home, and they may have other medications such as antibiotics and prokinetic medication. Make sure you know what medications your rabbit needs, how much and how often and ask your veterinarian or vet nurse to demonstrate how to give these. If your rabbit is not eating normally, they are likely to need syringe feeding. Again, get your veterinarian or veterinary technician/nurse to demonstrate this to you. You need to check the wound several times a day to make sure it is clean, dry and there is no bleeding or swelling – if anything is of concern to you then contact your veterinarian straight away. Rabbits rarely need to wear buster collars to prevent them from scratching. These are stressful for them to wear and stop them eating their cecotrophs droppings, but you do need to make sure they do not scratch at the wound area. There may be sutures that need to be removed, or these may be dissolvable. Your veterinarian will advise when they need to see your rabbit back for further checks.

Complications immediately after enucleation surgery are like any other surgery including pain, bleeding, swelling, drainage, infection, pain and wound breakdown. Some swelling is normal after the procedure, but it is best to check with the veterinarian if this occurs. Long-term complications are uncommon. Be sure to discuss any concerns you have with your veterinarian prior to the procedure.

Anesthesia is generally very safe but there are always risks. This applies to all species and all procedures, however in most cases, the risks are minimal. A good rabbit savvy veterinary team will ensure all risks are minimized using comprehensive attention to the best protocols that ensure a successful outcome. This includes an evidence-based approach to choosing the safest most effective drugs for rabbits, and careful monitoring by trained and qualified veterinary nurses during the surgery and during the recovery period.

You will need to check your own policy and speak to your insurance provider. As a rule of thumb, unless you are within your initial exclusion time as you have just taken out the policy, the rabbit has exclusions on their policy, or you have reached your policy limit, you should be covered, but you will need to clarify with your insurance company and potentially get them to go a pre-authorization claim to determine if you will be.

Yes, absolutely. Rabbits who require enucleation often have an extremely painful and non-functioning eye with very limited vision so removal of this eye can significantly improve the rabbit’s quality of life. Over time, the rabbit will adjust, and you can help with this by being aware of the new ways that you can support it with the loss of vision. As the rabbit has no eye on one side, it will have a blind spot there. Always try to approach your rabbit from the side they can see from, so they are not startled. Avoid having high ramps or shelves for the rabbit to sit on as they may fall off these more easily. Make sure that food and water is easy for the rabbit to access. Take care when cleaning the area as they will use their other senses, such as smell to recognize their environment, and changes to this can cause stress. It is unusual to have to remove both eyes, but if your rabbit loses both eyes, it will be completely blind and will take some time to get used to its new way of living. To keep the blind rabbit safe, keep it indoors and keep the environment stable so they can memorize the layout and move around with ease. The blind rabbit will adapt to using more of its hearing and sense of smell so you can avoid startling them by talking to them as you approach. Having a companion rabbit is a must for all rabbits and especially those who have limited or no sight, as they will rely upon the other rabbit more for support and to alert them to potential danger.