Ear infections are one of the most commonly diagnosed diseases in dogs and cats. We have previously discussed otitis externa. Otitis externa is often cured with ear cleaning and drops with minimal problems. However, if left untreated or in severe cases, an aural (ear) hematoma may develop. A hematoma is swelling created by a broken blood vessel after bleeding has occurred inside a tissue.
Otitis externa develops due to a lack of oxygen flow through the ear canal. The air flow can be disrupted for a number of reasons. A dog’s ear canal has a vertical and a horizontal component. This structure predisposes dogs to ear infections as debris must work its way upward rather than straight out. Dogs that have droopy ears, excessive hair in their ears, or narrowed ear canals, have an increased chance of ear infections. Dogs that are bathed or swim regularly are also at a higher risk of developing ear infections. Breeds that are predisposed include Cocker Spaniels, Labrador Retrievers, and Poodles.
Once air is not circulating normally in the pet’s ear canal, moisture begins to accumulate leading to inflammation. The inflammation then narrows the ear canal even more exacerbating the problem. The damp, humid environment that follows is ideal an ideal growing environment for bacteria and yeast. Once the infection, along with the inflammation, settles in, it isn’t long before the pet is seen scratching at his ears, shaking his head or holding one ear tilted. Discharge and odor may be noticeable at this point.
Aural hematomas occur when head shaking and scratching breaks a blood vessel between the cartilage and skin of the ear and the space begins to fill with blood. The ear may partially or completely swell with blood. The ear will feel fluid filled, like a water balloon and be painful to the touch. The ear is often warm and red. The pet will hold the head tilted, with the affected side down. Diagnosis of aural hematomas is generally straight forward, done by feeling the hematoma and identifying the ear infection. Confirmation of otitis externa involves collection of ear swabs to examine under the microscope.
Treatment of aural hematomas is multifactorial. The priority of treatment is to resolve the hematoma without narrowing the opening to the ear canal. This is done surgically. The dog will undergo a general anesthesia to have the blood drained from the space between the skin and the cartilage. The space that the blood created will be closed with sutures, preventing more blood from accumulating. The procedure involves suturing the skin to the cartilage in multiple locations. The ear infection must be treated as we have previously discussed. The condition is painful for the pet and therefore requires treatment for the discomfort. Pain control may involve anti-inflammatories or in severe cases, the condition may warrant opiods (morphine type drugs).
At Twin Valley VHS, we do not recommend draining the hematomas. The accumulated blood will act as an ideal growing environment for bacteria. Therefore, if there is any infection on the ear, the infection will have gained access to under the skin. Also, by draining the blood, a space is created in the ear and the pressure from the ruptured blood vessel is relieved. This will lead to refilling of the hematoma almost immediately.
At Twin Valley VHS, we strongly recommend treating aural hematomas. If left alone, the blood will be re-absorbed back into the body. However, a cauliflower ear will result. There is a lot of scarring associated with the process of re-absorption. The cauliflower ear will minimize the opening of the ear canal, exacerbating the current infection and predisposing the pet to future ear infections.
If you have any questions regarding the above information or any questions/concerns in general, please contact Twin Valley VHS at 745-6642.
Dr. Justin Noble DVM
Twin Valley Veterinary Health Services