This section is from the book "Sporting Dogs. Their Points And Management In Health, And Disease", by Frank Townend Barton. Also available from Amazon: Sporting Dogs; Their Points and Management in Health and Disease.
Long-eared dogs — more especially Spaniels and Retrievers—are very liable to suffer from this complaint. In some instances the causes are, probably, of a constitutional nature, but as a rule it is the result of a bruise.
The bruise gives rise to the production of an inflammatory effusion between the skin and cartilage of the external ear, causing a baggy-like swelling, compressible with the finger, and alterable in shape when the external ear is manipulated.
The old, and by far the most satisfactory way of dealing with this serous (watery) abscess is to make a free cut into it. Introduce the finger into the wound and break down adhesions ; then wash out with a little iodine and water. Keep wound open for a few days. This will always effect a cure.