Chronic suppurative otitis media (COST) is a chronic purulent inflammation of the middle ear mucosa, ossicles or deep into the bone. The lesions are not only located in the tympanic cavity, but also often invade the tympanic sinus, mastoid process and eustachian tube. The disease is very common. Clinically, it is characterized by long-term intermittent or persistent pus flow in the ear, tympanic membrane perforation and hearing loss; under certain conditions, it can cause intracranial and extracranial complications. I. Etiology ① Acute suppurative otitis media is not properly and thoroughly treated, and the course of the disease is prolonged for more than 8 weeks, or acute necrotizing otitis media with lesions deep to the bone. ②The presence of adenoid hypertrophy in the nose and pharynx, chronic tonsillitis, chronic purulent sinusitis and other diseases may cause otitis media to recur and remain untreated for a long time. ③Decreased systemic or local resistance, such as malnutrition, chronic anemia, diabetes mellitus, etc. Infants and children with low immune function are more likely to develop chronic otitis media when they have acute otitis media. The common pathogenic bacteria are Staphylococcus aureus, Pseudomonas aeruginosa, Proteus, Klebsiella, and so on. In longer cases, there is often a mixture of two or more bacteria, and the strains often change. Mixed infections of aerobic and non-budding anaerobic bacteria are gaining attention. Fungal infections of the middle ear are rare. Pathology The main pathological changes of this disease are mucosal congestion, thickening, round cell infiltration, and active secretion of cupped cells and glands. The lesion may be located mainly in the tympanic chamber, but may also invade other parts of the middle ear. If the mucosal epithelium is disrupted and the inflammation invades the underlying bone, such as the auditory tuberosity, the inner wall of the tympanic chamber, the tympanic sulcus, the tympanic sinus, the mastoid process, or even the facial nerve canal, chronic osteoarthritis (osteitis, erosion) may occur, with localized granulation or polyp formation, and rarely with foci of sclerosis or tissue adhesions. In marginal perforations of the tympanic membrane or large perforations with persistent inflammation, squamous epithelial metaplasia may occur after mucosal destruction, or secondary cholesteatoma. Symptoms 1. Ear overflow Ear overflow is intermittent or persistent for a long time. Ear overflow attacks or increases when there is an upper respiratory tract infection or reinfection via the external ear canal. The secretion is mucus-pus, either thin or thick, and in the case of granulation or polyps, the secretion may occasionally be mixed with blood; the amount of secretion varies. 2.Hearing loss The degree of hearing loss varies, and may be unnoticeable in mild cases, but may be felt only when the hearing loss is severe. 3. Tinnitus Some patients may have tinnitus. If the perforation is surrounded by residual tympanic membrane, regardless of whether it is located in the central or peripheral part of the tympanic membrane, it is called central perforation; if part or all of the edge of the perforation has reached the tympanic groove and there is no residual tympanic membrane there, it is called marginal perforation. The mucosa of the inner wall of the tympanic cavity is congested, swollen, thickened, uneven, or with granules or polyps, and large granules or polyps may extend through the perforation in the external auditory canal, so that the perforation is covered and not visible. There is purulent discharge in the tympanic chamber or around the meatus and in the external ear canal. 2. Hearing test Pure tone hearing test shows conductive or mixed hearing loss with varying degrees of severity. A few may have severe sensorineural hearing loss. 3.High resolution CT scan of temporal bone If the inflammation is mainly confined to the mucosa of the tympanic chamber, the papillae are mostly pneumatized and well inflated. If there is bone ulcer, mucosal thickening or granulation, the air chamber is blurred and there is soft tissue shadow inside. In this case, the papillae are mostly of the plate block type or sclerotic type. Diagnosis Based on the medical history and examination results, the diagnosis is not difficult. It should be differentiated from the following diseases: 1. Chronic tympanitis: There is long-term pus in the ear and more granules on the tympanic membrane, while CT of the temporal bone shows normal tympanic chamber and mastoid process. 2. Middle ear cancer: It occurs in patients above middle age. Most of them have a history of long-term pus flow in the affected ear, recent bleeding in the ear, accompanied by ear pain, and may have difficulty in opening the mouth. There are new organisms in the tympanic chamber and contact bleeding. Facial palsy is present in the early stages, with late manifestations of VI, IX, X, XI, and XII cerebral nerve damage. CT of the temporal bone shows bone destruction. Biopsy of the neoplasm can confirm the diagnosis. 3. Tuberculous otitis media: insidious onset, thin pus in the ear, obvious hearing impairment, early onset of facial palsy. Large perforation of the tympanic membrane with pale granulation. CT of the temporal bone shows areas of bone destruction and dead bone in the tympanic chamber and mastoid process. Tuberculous lesions in the lungs or elsewhere. Granulomatous examination can confirm the diagnosis. Treatment The principles of treatment are to control infection, improve drainage, remove the lesion, restore hearing and eliminate the cause of the disease. 1.Medication ①If the drainage is unobstructed, local medication is the mainstay, and in case of acute inflammation, systemic antibiotics should be applied. ②If available, take the pus for bacterial culture and drug sensitivity test before using drugs to guide the use of drugs. (1) Local medication types: ① antibiotic solution or antibiotic and glucocorticoid mixture, such as 0.3% Ofloxacin otic solution, rifampicin otic solution, 0.25% chloramphenicol otic solution, etc. etc. It is used when the mucous membrane of the tympanic chamber is congested and edematous, and when there is more secretion. ②Alcohol or glycerin preparations, such as 3%-4% boric acid glycerin, 3%-4% boric acid alcohol, 2.5%-5% chloramphenicol glycerin, etc. It is suitable when there is little pus and the drum chamber is moist. (2) Precautions for local medication: ① Thoroughly wash the pus in the external auditory canal and tympanic chamber with 3% hydrogen peroxide or saline before medication, and wipe it dry with cotton swabs or suck it up with an aspirator before medication is administered; ② Avoid using aminoglycoside antibiotic preparations (such as neomycin, gentamicin, etc.) for ear drops to avoid ototoxicity; ③ Avoid using powder if there is a lot of pus or small perforation, otherwise it will affect drainage and even lead to complications; ④ Avoid using (4) Avoid using corrosive agents. 2. Surgical treatment (1) If there are buds or polyps in the middle ear, or if no obvious buds or polyps are seen under otoscopy, but regular drug treatment is ineffective, and CT shows obvious mastoid lesions, mastoid opening + tympanoplasty should be performed. (2) If the middle ear inflammation has been completely absorbed and the central perforation of the tense tympanic membrane remains, simple tympanoplasty is feasible.