answer:An adult cat is unlikely to have ear mites unless it has immune issues or is hanging out with some unsavory characters. The location of the scabs sounds as if they are self-inflicted, as the result of a chronic itch. If she has a bad ear infection, she may be scratching. An allergy to fleas is also possible (and the most common), as well as some other environmental allergy, or a food allergy. Your best bet is to follow up with your veterinarian or a veterinary dermatologist. Depending on the severity, treatment with a steroid and possibly an antibiotic may be required. (Make sure that you understand the risks associated with steroid treatment – many vets are too prone to treating steroids as a completely innocuous drug, which it is not.)