Updated: Apr 9
Canine haematoma, also known as auricular hematoma or "cauliflower ear," is a condition in dogs that results in the accumulation of blood between the skin and cartilage of the ear flap. These fluid-filled swellings usually develop on the concave surface of the pinnae in dogs, cats, and even pigs. Why the concave aspect of the pinna is usually affected is not known. This is most commonly seen in dogs with floppy ears, such as Basset Hounds, Cocker Spaniels, and Pit Bulls.
What causes Canine Haematomas?
Canine hematomas are suspected to be caused by trauma to the ear, such as shaking the head or clawing at the ear, which can cause blood vessels to burst and flow into the tissue. The actual source of canine hematomas is unknown. Infection, allergies, and immune-mediated conditions are among more potential causes.
The ear canals are the principal sites of allergic inflammation, pruritus, and secondary infection in dogs with the syndrome, which is found in conjunction with atopic dermatitis and food allergies. The pinnal cartilage might even be damaged due to an immunological reason, according to some theories. The swelling that results from the serosanguinous fluid within the lesion is typically extremely painful.
What factors increase the risk of canine haematomas?
Concurrent ear conditions, such as otitis externa, aural foreign bodies, increased blood vessel fragility caused by diseases like Cushing's disease (Hyperadrenocorticism), or disorders of the clotting mechanism (hemostasis), which are primarily inherited, are the common predisposing factors for canine hematomas. Breeds that are more likely to get otitis externa are also more likely to develop hematomas, e.g., Basset Hounds, Cocker Spaniels, German Shepherd Dogs and Pit Bull Terriers.
How is Canine Haematoma Treated?
Treatment for canine hematoma typically involves draining the accumulated blood and stabilizing the ear to prevent re-accumulation. This can be done through various methods, including surgical drainage, needle aspiration, or a special bandage or splint. In some cases, medication may also be prescribed to reduce inflammation and prevent infection.
Less aggressive treatment may be more effective for hematomas that have been present for less than a week, e.g., fine-needle aspiration of small hematomas, with or without injection of corticosteroid. According to general guidelines, the fluid should be drained, fibrin should be removed, and dead space should be removed.
The diagnosis and careful treatment of the underlying ear condition is a crucial component of the treatment because if they are not, the hematoma may return.
If left untreated, a canine hematoma can lead to permanent deformity of the ear and discomfort for the dog. It is therefore essential to seek veterinary care as soon as possible if you suspect your dog may be suffering from this condition.
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