Typically, ear infections begin with otitis externa and then progress deeper into the canal to the middle ear. When the inflammation in this region of the ear is chronic, the eardrum may rupture and the infection may spread to the inner ear -- or, the infection may begin in the middle ear and progress outward to the external ear. Of the three types of otitis, infections in the inner ear are often the most severe and can lead to partial deafness and neurological problems.
In serious cases of otitis, the skin begins to form into folds in which the infection can become trapped, making cleaning and use of topical treatments very difficult. In addition, in cases of otitis interna, the skin will secrete more wax and debris that allows yeast and bacteria to overgrow, causing further disease. Severe inflammation leads to permanent skin thickening, mineralization, and narrowing of the ear canals. Once this occurs, the only viable treatment will be surgical removal of part or all of the ear canal.
