Benign meibomian gland cysts in dogs are non-cancerous. They originate in the meibomian gland (or sebaceous glands) of the eye. They tend to occur in older dogs and can affect any breed.
Are you worried about any unusual lumps and bumps in or around your dog’s eyes? If so, it’s a good idea to make an appointment with a licensed veterinarian for proper diagnosis. There are a variety of eye problems (listed within this post) that can occur in dogs.
This post will give you a better understanding of what benign meibomian gland cysts in dogs are, when surgery is recommended, what surgery involves, and post-treatment recovery. In addition, you’ll learn about the possibility of meibomian tumor recurrence.
What Are Meibomian Glands in Dogs?
The meibomian glands are the oil-producing glands (sebaceous glands) found along the eyelid margins. They’re not underneath the eyelid; rather, they form on the ridge just below or above the lash line. These glands become dysfunctional if blocked, leading to swelling within or on the margins of the eyelid.
Meibomian glands are responsible for oil secretion (sebum) and help prevent the eyes from drying out. The oil coats the eye and prevents the teary water component from evaporating.
People have the same glands that form the same function. Everytime we blink (or your dog blinks), the meibomian glands secrete a small amount of sebum to protect the eyeball. This oily substance is what keeps our eyes from drying out.
The same dysfunction can occur in dogs. Take a look at the TearScience website to find out more about the effects of meibomian gland dysfunction. Although the information presented is for people, the same principles apply to our canine friends.
Meibomian gland cysts in dogs are tiny little nodules that can form in what’s known as the “third eye”. The third eye (aka nictitating membrane) is the tissue you see in the corner of the eye. If you watch your dog blink, you’ll see movement of that membrane.
Will My Dog Go Blind?
Meibomian cysts or tumors occur on or under the eyelid margin. Initially, they are quite small and your dog might not even notice them. It’s unlikely your dog would go blind, but if these cysts are left unchecked, they could potentially grow large enough to irritate the cornea. That irritation could, conceivably, cause the cornea to become infected and ulcerate.
What Are the Symptoms of Eyelid Tumors in Dogs?
Meibomian tumors (also called chalazions) don’t show early obvious symptoms other than the swelling of the cyst itself. They do not cause dogs pain. However, if the cyst is left to grow, there is the possibility it could become big enough to cover and irritate the retina. The size of the cyst can block your dog’s vision. As the lump grows, you may start to notice redness in your dog’s eye.
There’s a good chance you won’t notice any issue with your dog’s eyes until a benign cyst forms. In rare cases, the cysts may disappear on their own, but it’s not likely. Over-the-counter antibiotic drops or creams will not make them go away.
What Should I Do If My Dog Has Meibomian Cysts?
If your dog is showing signs of eye irritation, and there’s nothing obviously wrong (like a piece of grass or fleck of dirt in the eye), make an appointment to see the veterinarian. Also, just because the oil glands show signs of dysfunction doesn’t mean your dog has tumors. Listed below are a variety of other eye diseases that can affect dogs.
Dogs have an uncanny ability to hide pain from people. However, you might notice subtle signs that something is wrong. A dog will lick at spots that are irritated or uncomfortable. Of course, they can’t lick their eyelids. Instead, you might notice your dog pawing at the eye. Dogs will sometimes take their entire paw and rub it over their heads and down over the eyelid.
Common forms of eye problems in dogs.
Conjunctivitis or pink eye
Can Meibomian Gland Cysts become Cancerous?
It’s highly unlikely that meibomian gland cysts in dogs will become cancerous. That said, I am not a veterinarian and I cannot diagnose your dog. It can’t be stated enough: If you suspect any problems with your dog’s eyes, please bring him/her to a licensed veterinarian as soon as possible.
Will My Dog Need Surgery?
There are a few ways a veterinarian could approach the treatment of benign meibomian gland cysts in dogs.
In some cases, meibomian cysts could disappear on their own. In order to do that, however, the dysfunctioning gland needs to be addressed. If the condition is very mild and in its early stages, properly cleaning the eyelids with warm compresses.
The veterinarian might choose a wait-and-see approach if the cysts are tiny and pose no threat to the dog’s quality of life.
Surgery Without Anesthesia (Local)
Some dogs can tolerate the removal of benign meibomian gland cysts with a local freezing and some can’t. A “local” refers to freezing just the area around the cyst. You dog stays awake during this painless procedure. For this to be successful, your dog needs to be particularly calm.
Surgery with Anesthesia (General Anesthesia)
Local anesthesia (staying awake during the procedure) is less risky than being put under. However, depending on the severity of the cyst and the temperament of your dog, general anesthesia might be preferable. Keep in mind that general anesthesia will cost more than a local.
What Are the Risks of Anesthetizing My Pet?
Risks of general anesthesia include choking on vomit (if your dog hasn’t been properly fasted in advance), serious allergic reaction (anaphylactic shock), aspiration pneumonia, and in rare cases heart, liver, or kidney failure.
If your dog is otherwise healthy, the risks are low. Your dog might have mild swelling at the injection site which is not considered serious.
Since older dogs are more likely to have pre-existing conditions, the veterinarian may prefer to try a local anesthetic instead.
Evaluating Your Pet’s Condition Pre-Anesthesia
Meibomian gland cysts in dogs are not life-threatening and, for that reason, surgery can be scheduled well in advance. That gives the veterinarian time to explain the pre-surgical procedures. For example, dogs should be fasted up to 12 hours before surgery.
If your dog is currently on medications like blood thinners, the veterinarian may ask you to reduce the dosage or stop the medication just before the surgery.
NOTE: Never stop your dog’s medication without first consulting with a veterinarian. Always follow your veterinarian’s orders regarding pre-surgical preparation for the best possible outcome.
Medications Used in Surgery
Veterinarians have a variety of medications to choose from when performing surgery. Before surgery, dogs are usually given a sedative like Butorphanol. Butorphanol is thought to reduce post-operative pain and helps the general anesthetic work faster. The anesthetic itself could be something like Sevoflurane, an inhalation agent.
Please visit the Canine for Veterinary Health Services for more details on anesthetic medications.
Surgery for benign meibomian gland cysts provides complete removal of the eyelid tumors.
After surgery, the veterinarian may prescribe pain killers, antibiotics, and anti-inflammatories.
An Elizabethan collar is recommended to prevent your dog from pawing at the affected eye.
The Reality of Post-Surgical Recurrence
In some cases, meibomian cysts will recur. Dogs and people may develop these benign cysts if they have a history of blepharitis (inflammation of the eyelids due to blocked oil glands) or conjunctivitis (inflammation of the conjunctiva). The conjunctiva is a thin mucus membrane that partially covers the eye.
Surgical removal of benign meibomian cysts is curative; however, there are hundreds of meibomian glands that can also become infected. In other words, that particular cyst can be removed and cured, but there are many other areas where more cysts can come back.
Cryosurgery is the most common way to surgically remove benign meibomian gland cysts in dogs. This is, essentially, where they freeze off the affected tissue.
A chalazion clamp is fitted over the cyst and the rest of the eyelid is covered for protection. The surgeon applies the device to the tissues which are frozen to at least -25 degrees using either carbon dioxide or nitrous oxide.
This action destroys the intracellular wall and ruptures the unwanted tumor. A similar action is performed in-office for things like warts in people.
Meibomian gland cysts in dogs typically occur in older dogs, although they can occur in all ages and all breeds. Pay particular attention to your dog’s eyes for any changes, however subtle. Redness, swelling, pawing at the area, crusting of the eyelids and fur loss around the eyes could be signs of trouble. Also watch the cornea itself for signs of opaqueness (cataracts).
Anytime your dog seems to be “off” is a good time to visit a licensed veterinarian. After all, you know your dog better than anyone else so trust your intuition.Follow Your Dog's Health Matters!