Medical Corner: Rat Ear Hematoma

Mary Ann Isaksen
From the September/October 1998 Rat & Mouse Gazette

Every so often we see a medical problem in our pet population that is extremely rare, and a hematoma in a rat ear, although not dangerous if treated, is one of those things that completely fits that description. In the over 20 years that I have had rats as pets, with well over 100 rats to use as a base, I have seen this happen only once. It was back in 1995, and at that time, I wrote a short plea requesting information from other rat owners in the May/June 1995 issue of the AFRMA newsletter, Rat & Mouse Tales. Until earlier this year, I had heard nothing more about this from anyone.

Atlas with a fluid-filled hematoma.

Hematoma before

In June of this year I received an Email from concerned rat owner describing what I thought could only have been a hematoma in the ear of his rat, Atlas. I was shocked to hear about it and recommended that he take Atlas to his vet to confirm what I suspected. Atlas' owner was kind enough to take a photo of Atlas' ear before going to the vet, and after the vet had surgically repaired the damaged ear - something I had failed to do when it happened to my rat. It was confirmed to be a hematoma.

Now, knowing of only two cases of a rat ear hematoma, we're publishing this short article to make it easier for rat owners to diagnose this problem and know to seek veterinary help for the surgery necessary to repair the ear. This article is not meant to offer any definitive information regarding this condition, since there is none to be found in reference to rats in any of the veterinary books that I have available. However, I have included information from The Merck Veterinary Manual that may be of some importance.



Hematomas of the outer ear are described as fluid or blood-filled swellings that develop on the concave surface of the ear in dogs, cats, and pigs. These may develop following the rupture of blood vessels within the tissues of the outer ear, as a result of head-shaking or ear-scratching due to itching. The condition is most common in dogs with long, floppy ears. It has also been proposed that this condition results from an autoimmune disease of the outer ear tissues, rather than from trauma.

Treatment is surgical to allow drainage and debridement. Underlying causes of otic discomfort, such as parasites or hypersensitivity diseases, should be identified and treated to prevent recurrence.

Atlas after surgery with some scar tissue

Hematoma after