My cat is almost 18 and is healty except...

Question
My cat for about ten years now has had open bleeding itchy sores that have gotten worse over time.  We have taken her to the vet time and time again, and all they could find is that it is a corn allergy.  We have cut corn out of her diet entirely and we clean her room and bathe her almost weekly.  These sores do not get entirely better and the worst of it is in her ears.  Do you have any ideas what it could be, or anything we can do to try to help her?  She isn't in a lot of pain from them, they just itch her a great deal unless you touch them too hard.  Euthanization is out of the question, because she is very happy and still seemes to enjoy life.  I just wondered if there was anything that we could do to ease this, we have tried many kinds of skin meds already but I'm open to most anything.

Thank you for you time.
Kamara.

Answer
You didn't tell me if she is on a regular regimine of flea medication. It should be GOOD quality flea meds like Frontline or Advantage that you can get at the vet. She could be allergic to fleas. If you are already doing this..you could try switching her to canned food which is a lot lower in carbohydrates than dry food.  Hope this helps!