When the Infection is So Bad the Entire External Ear Canal Has to Be Removed
A surgical solution for otitis externa.
Cocker spaniel Fred, an active dog who loves to chase deer and squirrels in the field behind his home, was about five years old when his owner, Dick Moreau, noticed that his pet had been shaking his head and scratching his ears. This went on for a couple of weeks until Mr. Moreau took a close look at Fred’s ears and found what looked like a growth inside the left one. He took Fred to the vet, who did not feel comfortable going deep down into the ear but removed what he could.
It was after the operation that Fred started to have chronic infections in both ears. “We were at the vet very, very often,” Mr. Moreau recounts. “You could feel a hardness underneath” each ear flap. “It protruded” on both sides. “We went through any number of medications,” he adds. “Some of them were antibiotics, and what made it all the more difficult was that Fred has had allergic reactions to antibiotics like amoxicillin.”
Finally, after a couple of years, recalls Mr. Moreau, the vet said that “we’ve reached the point that no matter what we try to treat Fred with, the canals are obstructed so badly that we’re not getting to the deep-rooted infection way down. Ultimately, I think the only solution you’re going to have is an operation called total ear canal ablation,” which veterinarians refer to as TECA.
Enter John Berg, DVM
Mr. Moreau’s veterinarian referred him to Dr. John Berg, a surgeon at Tufts Cummings School and the editor-in-chief of Your Dog. Dr. Berg wasn’t at all surprised by Fred’s condition. “Ear canal infections are among the most common conditions dogs get,” he says. “Most are manageable with medications, but with some, the infection becomes end-stage and requires a surgical solution.”
Mr. Moreau’s family practice vet had followed standard procedure by prescribing medications for Fred to try to vanquish the infection. First, the doctor will attempt to find the underlying cause of the infection, Dr. Berg says. Consider, he comments, that bacteria are “all over the place. But if a dog’s skin is healthy, he won’t get a bacterial infection. It takes any of one of a variety of situations to cause the bacteria to gather and cause illness. It could be an underlying allergy to food or an environmental allergy, or foreign material in the ear canal, or even a tumor in the ear canal. Tumors on the surface of the body are not normal tissues, so they don’t have the normal defense mechanisms for keeping an infection from developing.”
An otoscopic exam sometimes yields clues. The doctor puts the little otoscope cone into the dog’s ear and closes one eye to better see through the lens that magnifies what’s in the ear canal. But often enough, Dr. Berg says, the underlying cause can’t be identified, so the veterinarian simply treats the infection, which is what happened with Fred.
Sometimes that works, says Dr. Berg, “sometimes not.” One of the most common reasons it doesn’t, he explains, is thickening of the lining of the ear canal in response to the chronic infection. The lining also gets wrinkly, Dr. Berg says, and the canal itself, normally made of rubbery cartilage, becomes hardened with calcium deposits. In the end, he comments, “the ear canal becomes this very thick, hard thing that’s very painful for the dog. And the lumen — the opening of the canal — becomes pinched off.” It’s called end-stage otitis externa, “otitis” meaning ear infection and “externa” meaning in the external ear canal.
You can actually feel a bump on the outside of the ear where the canal has thickened, just as Mr. Moreau was able to feel the protrusions outside each of Fred’s ears when he lifted the dog’s ear flaps. Adds Dr. Berg, “it’s kind of a uniquely cocker spaniel problem,” which is why he wasn’t at all surprised to see that it had occurred in Fred. He says that “sometimes English bulldogs develop it, sometimes German shepherds, or French bulldogs. Almost any dog could get it. But cockers are by far the most usual victims.”
Concerns about the operation
Total ear canal ablation, performed when it’s beyond hope that the infection will respond to medical management, is total removal of the ear canal. It’s usually bilateral, meaning the end-stage infection has taken hold in both ears. Many owners, by the time the operation is recommended, are so frustrated with trying to make the disease go away they’re glad for a new option, Dr. Berg says. However, given that both external ear canals are removed, their usual first question is: “How is my dog going to hear?”
“But this is not a surgery that’s really about hearing,” Dr. Berg says. “It’s about pain, about making a dog comfortable. Remember ear pain as a little kid? Imagine constant pain like that going on for months or years.” A lot of owners don’t recognize the severe pain that the head shaking and ear scratching indicate, he comments.
Besides, Dr. Berg says, some dogs actually hear better after the operation. “They’ve got this mass of calcified tissue that’s blocking sound transmission, like a thick horn felt through the skin on either side of the skull, and then it’s removed. Electrical tests of hearing both pre- and post-surgery have been done. The most common change is that the dog’s hearing gets better. All the abnormal tissue interfering with the ear’s function is removed. Granted, there’s no opening where the ear canal was when you lift up the dog’s ear. But the sound goes straight through the tissues. One dog I treated, after his surgery, was able to hear the clicking of the turn signal in the car again. He always knew it meant his owner was turning into the park where he could start to play, and he’d get excited. That response returned.”
The surgery itself
A total ear canal ablation involves more than removing the thickened, calcified, wrinkled external ear canal. The middle ear, a cavity that contains the tiny bones responsible for amplifying sound waves, is involved, too, because the infection has inevitably spread there. “What separates the external ear canal from the middle ear is the ear drum,” Dr. Berg explains. “In dogs that have severe, chronic end-state otitis externa, the ear drum almost invariably gets eaten away by the infection, so the infection extends right into the middle ear as well. When we do the surgery, we enlarge the opening into the middle ear so we can remove as much of the infection from there as possible.
“But you cannot physically remove all of the infection from the middle ear,” he says. It literally goes into the bone, and you can’t remove all the bone. For that reason, a dog needs to be on antibiotics after the surgery to get rid of any residual infection that’s bound to be there.
That was the case with Fred. For five weeks post-operatively, he was on antibiotics to kill any infection-causing bacteria still lurking.
“Overwhelmingly,” says Dr. Berg, “the majority of dogs have a complete resolution of their infection. They become normal, happy, pain-free dogs again.” In fact, he says, a lot of owners interpret their dog’s return to exuberance and activity as a sign that their pet can hear once again. “But it’s really that the dog is not in pain anymore,” he comments. Still, there are a couple of potential complications.
One is that a facial nerve located very close to the ear canal is susceptible to damage during the surgery. When damage does occur, it’s usually temporary, lasting a week to a month. “The nerve just kind of gets a little traumatized,” Dr. Berg says. “But artificial tears are required until it heals because it’s the nerve that’s responsible for tear production. We know by the morning after the procedure. If the dog isn’t blinking properly, we administer the artificial tears.” Fred had that complication on his left side, in combination with a little drooping on the left side of his face. But it cleared up in a week.
The other possible complication is that some dogs have such highly resistant bacteria in their middle ear canal that the usual arsenal of antibiotics doesn’t kill them and there’s a relapse of serious infection even though the dog has gone through the surgery. “So on rare occasions,” Dr. Berg says, “we’ll see dogs come back six months to a year later shaking their heads again or scratching the side of their face, or even having some drainage on the side of their face — all signs of an infection.” The antidote is often a very extended course of antibiotics. “You can keep the infection down to a dull roar with long-term antibiotics,” Dr. Berg says, although in some cases “repeating the surgery is the best option.”
Fortunately, Fred had his operation months ago and there has been no return of infection. “The surgery went great,” Mr. Moreau says. “He’s laying at my feet right now, not shaking his head, not scratching his ears. He’s very comfortable.
“I brought Fred in on a Monday night,” Mr. Moreau adds, “and Dr. Berg was going to operate early Tuesday morning. But he texted me on Tuesday that the operation before Fred’s was taking more time than expected. That way, I knew he wouldn’t be going in till about 11,” a communication Mr. Moreau appreciated because, he says, “as a pet owner you worry like crazy.” You want to know when your pet is actually on the table. You don’t want to think he was wheeled into the OR at 8 and you haven’t heard from the doctor after hours and hours of operating.
Dr. Berg was pleased with the proceedings, too, not to mention the results. “There are many dogs out there like Fred,” he says, “who are suffering with chronic ear infections that aren’t responding to medical therapy but for whom there’s a good solution to their pain.”á