Thank you for your question.
There are 2 possible reasons for the balloon- like ear.
An aural hematoma occurs when there is breakage of small blood vessels in the ear flap. The bleeding that ensues gets entrapped between the skin of the ear and the cartilage of the ear flap and creates a heavy hematoma in the ear flap.
Aural hematomas are usually associated with an underlying ear infection
, which causes the pet to shake the head from the itch. The flapping of the ears from the head shaking causes the vessel rupture and subsequent bleeding.
Aural hematomas are best fixed via surgical drainage and placement of a drain or suturing of material to the ear flap to prevent blood from re-forming the hematoma. Aural hematomas will eventually resolve on their own by cause the ear flap to become wrinkled and deformed and predispose to future ear infections.
The second possibility is an abscess from a cat bite. An abscess is an infection that becomes trapped under the skin secondary to a fight with another animal (usually another cat).
If Vigo is an indoor/ outdoor kitty, this is a possibility. It's less likely if he is indoor only, and of course, impossible, if he is the only pet in the home.
If Vigo does go outside and there is the possibility that this is an abscess, the sooner it is addressed, the better. Infections like these can enter the blood stream and make the cat very ill.
If there is no possibility that this is an abscess (he's indoor only and an only cat), then it is likely an aural hematoma. This can wait until tomorrow when you visit your regular vet. Don't give Vigo food
or water after midnight tonight, in case your vet wants to anesthetize him for surgery to treat the hematoma tomorrow.