A fundamental distinction is made between operations on the outer eye (without opening the eyeball, e.g., lid surgery) from operations on the inner eye, in which the eyeball is entered (e.g., surgery of a displaced or cloudy lens).
All operations on the eye demand the greatest precision for we know from our own experience that even a tiny speck of dust in the eye feels like an enormous lump of rock. For this reason, every eye operation is generally performed with the aid of various magnification techniques in order to obtain an optimal result.
The best magnification and overview are provided by an operating microscope:
Nearly all eye operations on our pets must be performed under general anaesthetic. This is the only way to guarantee success in this high-precision surgery.
In addition to suitable magnification techniques and the surgeon’s skill, the correct instruments contribute significantly to the success of an eye operation. A microsurgical forceps is only as long as your thumb and the tiny hook at the tip of the forceps can hardly be seen with the naked eye.
A very fine thread is often used for suturing, which does not have to be removed after the operation. The thickness of the suture used to close the cornea is just 0.02 – 0.03 mm. For comparison, the thickness of a human hair is 0.05 – 0.07 mm - so twice as thick.
This explains why the eyes have to be treated particularly gently after an operation. Scratching or licking would rapidly remove such fine sutures. This is why it is obligatory for animals to wear a sufficiently large collar after nearly all operations, and they must be kept on the leash and kept away from other animals for a period of 10 - 14 days. Medications in drop or ointment form must nearly always be used directly on the eye in addition. Tablets are not always necessary.
Frequent questions asked by owners when their pet is to undergo an eye operation.
How long does an operation take and how long will my pet be under anaesthetic?
The actual operation time is usually not that long (between 30 and 60 min). Before it, however, an intravenous line is inserted, medications are given through the line and an infusion is set up to protect the organs during the anaesthesia. Sedation is given, the animal is intubated and treated with oxygen and anaesthetic gas, all the necessary anaesthetic monitoring equipment such as ECG, oxygen saturation, blood pressure measurement etc. is attached, the temperature is checked regularly, and the animal is warmed if necessary (especially in the case of small and young animals). The operation area may be shaved but is always cleaned and disinfected. Only then can the operation start.
How high is the risk of anaesthesia?
No higher than in other operations. The younger and healthier an animal, the lower the general risk of anaesthesia. In dogs and cats this is between 0.1-0.2%. Rabbits and small rodents have a somewhat higher risk.
What needs particular attention after an eye operation?
Scratching the eye, licking by other animals, excessive activity and head shaking are poison for a recently operated eye. Get your vet’s advice regarding a sedative, especially when you have a small tornado at home. Many animals feel “far too well far too soon” and don’t take things easy.
What must I be aware of when giving eye medications?
If you open the eye minimally, carefully and cautiously with freshly washed hands to put in drops or ointment, nothing can really happen. Take your dog or cat onto your knee or, with bigger dogs, position yourself in the corner of the room. Always approach from behind with the dropper or tube so that your pet doesn’t see it. Practice makes perfect and you must give a reward!
How can an eye function again if it has been opened up?
Whether due to a perforating foreign body (e.g., a thorn, cat’s claw) or in an operation, an opened eye loses intraocular fluid and collapses. It is therefore important not to remove a foreign body yourself but leave it in position. It sometimes acts as a “stopper”. During the operation, the eye is washed out with special solutions and refilled and it is then firm again as usual after it is sutured. After some time, the artificial eye fluid is metabolised by the eye itself and replaced by the animal’s own intraocular fluid, which is produced constantly.
Will my pet be able to see again directly after the operation?
A general answer cannot be given as every operation has different requirements. For instance, if a cloudy lens is replaced by an artificial lens (cataract surgery), the animal can see again directly after the operation. It is different with operations for glaucoma or severe injuries due to a foreign body. In this situation, the extent of the previous damage can sometimes be assessed correctly only after some time.
How much does an eye operation cost?
There is no general answer to this question either as it depends on many different factors: the type of eye disease and the required operation, the animal’s size and required medications, the type of anaesthesia, the time factor etc. All veterinary services must be charged for according to the Veterinary Fee Schedule (GOT), however. In addition, you can obtain a written estimate of the cost before every operation. Many eye operations are covered by all common animal insurance policies.
© AniCura, Teresa Keiditsch