People often use the phrase “sharp ears” to describe a person who has sharp eyes and ears, and a clear and organized mind. But if your ears are always dripping with pus, stuffy, and the pus is smelly, and you gradually can’t hear well, which seriously affects your normal work and life, beware of chronic suppurative otitis media. Ear structure: external ear canal → tympanic membrane → middle ear (tympanic chamber) To understand the origin of purulent otitis media, let’s first understand the structure of the ear. The outermost part of the ear is like a large secret passage. The corridor from the ear hole is the external auditory canal, and at the end of the corridor is the tympanic membrane; the first room in is the middle ear, also called the tympanic chamber. The middle ear is called the tympanic chamber because it is like a large drum. Air enters through the outer ear canal and is blocked by the tympanic membrane, causing it to vibrate and thus transmit sound to the inside of the ear. When the outside air pressure is high, the tympanic membrane is subjected to a lot of pressure. The secret passage in the middle ear, the eustachian tube, opens and closes to relieve the pressure in the ear So how do you relieve the pressure on the eardrum? In fact, there is a secret passage in the middle ear – the eustachian tube. This secret passage connects the middle ear to the nasopharynx and is normally closed, but occasionally opens at appropriate opportunities, such as opening the mouth, swallowing, yawning or chewing, to release the pressure inside the tympanic cavity and keep the pressure inside and outside the cavity balanced. Another interesting phenomenon is that the change in external air pressure during airplane takeoff can lead to ear stuffiness, which is usually relieved by a few swallows of saliva. This is a phenomenon that relieves ear stuffiness by opening the eustachian tube and balancing the pressure inside and outside the tympanic chamber. In other words, when the eustachian tube is present, the body has the ability to regulate the pressure inside the tympanic membrane on its own. Without the eustachian tube, however, the pressure in the middle ear cannot be regulated, and when the pressure outside the tympanic chamber > the pressure inside the tympanic chamber, it will lead to ear stuffiness, and when the pressure is too high, the tympanic membrane will be invaginated or even perforated, for example, by diving. Through the middle ear is the inner ear, which is the telegraph station for contact with the brain. Next door to this secret passage is the second chamber, the inner ear, which contains the cochlea and the semicircular canal and is connected to bits of auditory nerve fiber. The auditory tuberosity (also called the auditory chain) in the middle ear transmits the vibrational energy of the tympanic membrane to the cochlea in the inner ear, where it is processed and the vibrational signals of sound are converted into neurophysiological signals. So the inner ear is like a telegraph station, which eventually transmits the translated electrical signals to the auditory nerve up to the auditory center of the brain, and the person can hear sound! In chronic suppurative otitis media, the problem begins in the middle ear, and in patients with chronic suppurative otitis media, there is an intermittent or continuous purulent inflammatory reaction in the middle ear, and purulent secretions flow from the tympanic chamber through the perforated eardrum, causing pus to always flow from the external ear canal. On the other hand, if the inflammation persists for a long time, it will erode the soft tissues and bones inside the tympanic chamber, resulting in the growth of granulation in the middle ear and the destruction of the bone structure, which can also erode the auditory chain, causing symptoms such as ear pain, tinnitus, and hearing loss. Moreover, if the inflammatory secretions or buds block the eustachian tube, causing the tube to be unable to exchange air normally, the ear will be stuffy and no amount of nose pinching and puffing will help. Although not all patients will develop eustachian tube dysfunction, once it occurs, it will have a great impact on the surgery to improve hearing.