How do ears work?
This is a model of the ear and from here you can see the outer ear, which is made up of the oracle. This is the entrance to the ear canal here. If we remove this section here, we can see all of the different parts of the ear. This is the external auditory canal, which makes up the external ear, and this is an example of the tympanic membrane, which is on an angle, actually, and this is the eardrum. You can see that there, and then the bones of the ear, which are attached to the eardrum on the back side. This space here is the middle ear, and that's where middle ear infections occur. This tube here is the Eustachian tube which attaches to the middle ear and helps to regulate the pressure in the ear. So, Otitis Externa or swimmers ear would involve this part of the ear canal up to the eardrum, but it doesn't involve any of the rest of the system. Inflammation and swelling in this area is very painful, and this is what typically a swimmer would get if they maintain water in their ear. Otitis Media is an infection in the middle ear space, behind the eardrum, and is caused by bacteria that either travels up the Eustachian tube or fluid that is collected in the area just because of negative pressure and causes a middle ear infection. The difference between the adult Eustachian tube and a child's is that in the adult, the Eustachian tube is more vertical than in a child. In a child, the Eustachian tube is horizontal, so it allows bacteria and things like milk or food to get into this tube and cause inflammation that extends up into the middle ear.
