It is not known if treatment is medically needed or which treatment if used would be best for cosmetic reasons.
What if We Leave it Alone?
If left alone, an ear hematoma will go away or resolve by itself. The fluid will be re-absorbed back into the body and the ear flap will again be flat. The problem is that a lot of scarring is associated with this process and the ear is often not cosmetically appealing afterwards (a cauliflower ear). It can also take several months to resolve a large hematoma, which may be uncomfortable for the pet. If the patient is a poor anesthetic risk, it is certainly reasonable to forgo surgery.
see some methods of treament below
http://evidencebasedvet.com/forum/viewt ... ?p=460#460