Canine and feline aural hematoma: clinical, experimental, and clinicopathologic observations.

The pathogenesis of canine and feline aural hematoma (AH) was investigated. Clinical observations, selected experimental procedures, and clinicopathologic examinations were done on 40 dogs and 20 cats affected with AH. Eighteen healthy dogs and 14 healthy cats were used as the controls. The results of this investigation provide a valid basis for questioning the conventionally held view that AH is caused by trauma and for postulating that the actual cause is immune mediated.