Seroma of pinna:
Spontaneous Seroma of the pinna is a collection of serous fluid between the perichondrial layer of the pinna and the underlying cartilage. The etiology is usually unclear, and the condition tends to recur.
Treatment consists of needle aspiration or drainage of the fluid with application of a compression bandage (mastoid bandage) to the pinna. Drainage is necessary to prevent necrosis of the cartilage.
A short course of antibiotics, steroid and antinflamatory drugs are given.