How does a doc determines this is infective otitis externa when there is no pus or any ything like fluid.what other signs can determine otits externa?

Otitis externa: This type of infection is seen by looking into the ear canal. There is usually irritation, swelling and redness. Sometimes with more severe infections there can be bleeding or fluid. The infection is often treated with ear drops. Sometimes a wick is placed in the ear canal to help with getting the medicine to the correct area. Keeping the ears dry helps with healing.