Prolapse of the Tear Gland of the Third Eyelid

Cherry eye is another name for prolapse of the tear gland of the third eyelid. It's a relatively common condition, especially in small breeds.

The only possible solution for this prolapse is surgery. It's important to have it done, since cherry eye will irritate the eye's surface, potentially causing recurring conjunctivitis. Want to know all the details of this condition? Let's take a detailed look.

What Is the Third Eyelid?

Unlike humans, who have two eyelids, upper and lower, dogs have three. Their third eyelid is located at the inner corner of the eye. It plays a very important role in eye health. It's also known as the nictitating membrane. Normally, the third eyelid isn't visible to us.

But sometimes, it can extend or protrude and cover the eye fully or partially. It becomes visible especially in response to eye pain, more common when it affects a single eye. In addition, it can mean the eye has retracted. This condition is called enophthalmos. Since it can be due to different causes, we should seek veterinary care.

It's this professional who will give us a diagnosis and treatment. In these cases, we'll clearly see the extended membrane, opaque or whitish, emerging from the inner corner of the eye and covering it to a greater or lesser degree. This eyelid has a tear gland that can also prolapse. This is cherry eye.

When the Third Eyelid Is Visible

Although it can mean an eye problem, in some dogs seeing the nictitating membrane doesn't indicate any abnormality. These are dogs born with the third eyelid already extended.

In these cases, it's just a cosmetic issue that, as such, doesn't need any treatment. That said, these dogs can't take part in dog shows, since it's considered a defect.

On the other hand, in some breeds such as the Weimaraner, Great Dane, Golden Retriever, or Saint Bernard, what happens is that the third eyelid curls in on itself. This is a congenital problem known as cartilage eversion. These dogs do need treatment if the eyelid ends up irritating the cornea.

The Tear Gland of the Third Eyelid

In a normal eye, neither the third eyelid nor its gland are visible. But with cherry eye, the fibrous attachments inside this eyelid weaken. As a result, the gland ends up being exposed, and we'll be able to see it clearly.

We'll see a pink, rounded lump in the inner corner of the eye that, although it can worry and startle us, is nothing more than the gland. Given its resemblance to this fruit, cherry eye gets its name.

It can appear in just one eye, though it often ends up showing up in both. The main problem with this prolapse is that it irritates the eye's surface, eventually triggering conjunctivitis that won't go away as long as the prolapse persists.

Which Breeds Get Prolapse of the Tear Gland of the Third Eyelid?

This condition can appear in any dog, but it's more common in small breeds. It's considered a congenital defect, and because of this, some breeds have a higher incidence. These include the Cocker Spaniel, Beagle, Boston Terrier, or Bulldog, among others.

Treatment for Prolapse of the Tear Gland of the Third Eyelid

Since this prolapse is due to weakened support in the third eyelid, the solution involves repairing that support. To do this, surgery is essential.

During surgery, the third eyelid can either be removed or replaced. In addition, if there's conjunctivitis, the vet will prescribe antibiotic eye drops. But it's important to keep in mind that the eye drops don't cure the prolapse, only the infection it's caused.

Removal of the Tear Gland of the Third Eyelid

To fix the prolapse, it's easy to assume it's enough to remove the lump, meaning the tear gland of the third eyelid. But this gland has an important function, since it's responsible for producing a large portion of the eye's total tear volume.

So, if the vet removes it, we run the risk of causing dry eye syndrome, also known as keratoconjunctivitis sicca. This is characterized by thick discharge, which can also come with conjunctivitis. It's a condition requiring lifelong treatment and even surgery.

Repositioning the Tear Gland of the Third Eyelid

To prevent dry eye, another surgical option is to reposition and secure the third eyelid and its gland back in place. This resolves the problem without the risk of causing keratoconjunctivitis. It's very important that this surgery be performed by a vet specialized in ophthalmology.

Likewise, good post-operative care is essential so as not to spoil the surgery. To achieve this, we need to prevent the dog from touching its eye, and avoid rough games or movements that could put the area at risk. An Elizabethan collar will be needed. Proper veterinary follow-up and the medication the professional prescribes also need to be applied.

Bibliography Carlson and Giffin. 2002. Manual práctico de veterinaria canina. Madrid. Editorial el Drac.