Aural or Ear Hematoma

Why Is That Ear So Swollen?

An aural hematoma, or ear hematoma, is a collection of blood, serum, or a blood clot within the pinna (earflap). When present, the pinna will be very thick. The swelling may involve the entire pinna or it may involve only one area. We see these fairly commonly at the Animal Hospital at Thorndale, generally secondary to untreated ear mites or other ear or skin problems causing excessive scratching of the ears.

When something irritates the ear canal, the cat responds by scratching or shaking the head. Excessive shaking (trauma) causes blood vessels to break, resulting in bleeding. An understanding of the ear’s anatomy makes the sequence of event more logical.

The earflap is composed of a layer of skin on each side of a layer of cartilage. The cartilage gives the earflap its shape. Blood vessels go from side-to-side by passing through the cartilage. Violent shaking causes the vessels to break as the skin slides across the cartilage.

Treatment

There are two ways to treat aural hematomas. The first is to aspirate the blood from the earflap with a needle, inject a cortisone-like drug into the earflap, and, if needed, bandage the earflap to the top of the head. This is successful about 50% of the time. Because it is less involved and less expensive, some prefer to try this approach first. If it is not successful, the surgical approach is needed.

There are four steps in the surgical form of treatment.

1. The blood is removed from the pinna. This is accomplished by making a small incision on the inner side of the ear flap to expose the hematoma. The area is cleaned and flushed out. A drain may be placed to keep any additional fluid from accumulating. If a drain is placed, the ear will be bandaged over the top of the head to help catch any additional drainage.
2. The space where the blood accumulated is obliterated. Since the skin over the hematoma has been pushed away from the cartilage, it must be reattached to it to prevent another hematoma from occurring. This is accomplished by a series of sutures that are passed through the earflap.
3. The pinna is laid on top of the cat’s head and bandaged in place. Although the bandage may be somewhat cumbersome, it will prevent further damage to the pinna and allow proper healing to progress. An Elizabethan collar must be worn so the cat does not scratch at the ear. Sutures are removed in 10-14 days if they are not the type that dissolve on their own.
4. The cause of the problem is diagnosed and treated. Another important aspect of treatment is dealing with the cause of the shaking. If an infection is present, medication is dispensed to treat it. However, some cats have no infection but have foreign material (a tick, piece of grass, etc.) lodged in the ear canal. If so, the foreign material is removed. It is also possible that a foreign body initiated the shaking but was later dislodged. If that occurs, and no infection is present, further treatment of the ear canal is not needed.

Follow-up Care of Ear Hematoma

The bandage is generally removed in about 3-5 days. At that time, the hematoma is usually healed. There will be two holes in the skin where the drain tube entered. They will close within a few days. If discharge occurs from the holes before they close, it should be cleaned off with warm water.

If an infection was present, it will be necessary to recheck the ear canal to be sure that the infection is gone. Otherwise, another hematoma may occur.