Secretory otitis media is a common and frequent disease in otolaryngology, and is one of the common causes of deafness. Nasal endoscopic eustachian tube placement, which is performed through the natural channel of the eustachian tube with the express nasal endoscope, provides a good minimally invasive treatment route for secretory otitis media by avoiding the disadvantages of tympanic membrane damage and repeated operations of traditional methods. In order to explore the factors affecting the efficacy of nasal endoscopic eustachian tube placement for the treatment of secretory otitis media, the clinical data of 82 patients (97 ears) with secretory otitis media were retrospectively analyzed and reported as follows. 1. Clinical data 1.1. General data From September 2004 to June 2006, a total of 82 patients (97 ears) with secretory otitis media were admitted to our hospital and underwent nasal endoscopic eustachian tube placement after repeated outpatient conservative treatment had failed, including 48 inpatient cases and 34 outpatient cases, 33 males (39 ears) and 49 females (58 ears), with an average age of 34.5 (12～66) years. The clinical symptoms were generally stuffy ears, ear blockage, hearing loss, and tinnitus in some patients; on examination by otoscopy, nasal endoscopy, or electronic laryngoscopy, the tympanic membrane was mostly found to be invaginated or cloudy, with tympanic fluid in 60 cases (68 ears). The acoustic impedance map showed B-type in 60 cases (68 ears), As-type in 10 cases (13 ears), and C-type in 12 cases (16 ears); pure tone audiogram showed conductive deafness in 74 cases (87 ears) and mixed deafness in 8 cases (10 ears). The average hearing loss of speech frequency air conduction ranged from 20 to 45 dB, with an average of 36.5 dB. Among the 82 cases, there were 27 cases of chronic rhinopharyngitis, 19 cases of chronic sinusitis, 11 cases of adenoid hyperplasia, 8 cases of chronic hypertrophic rhinitis, 6 cases of nasal polyps, 7 cases of allergic rhinitis, and 4 cases of nasopharyngeal cancer. 1.2. Surgical method Patients were placed in the supine position, and appropriate treatment was performed for obstructive lesions in the nasal cavity before surgery. Under 300 nasal endoscope, 1% bupivacaine with ephedrine tampon was used for nasal mucosal surface anesthesia and contraction three times. The morphology of the pharyngeal orifice of the eustachian tube was photographed and recorded. After repeated cleaning of the pharyngopharyngeal opening with antibiotic solution and saline, the pharyngopharyngeal opening was carefully aspirated, and a metal Euclidean tube was inserted and embedded in the pharyngopharyngeal opening. Mark with gentian violet the expected depth of the epidural catheter to be inserted into the eustachian tube (usually 2.5 cm). If the epidural catheter is introduced about 2.5 cm along the Euclidean tube, there will be a feeling of emptying, indicating that it has passed through the isthmus of the eustachian tube. After slowly pumping the tympanic ventricular fluid, repeatedly inject and pump back 0.5 to 1 ml of air with a 1 ml syringe for 3 to 6 times to loosen the tympanic ventricular adhesions, and then inject 0.5 ml of the prepared mixture (usually prepared with 2 ml of diflucan injection + a chymotrypsin 5 mg + dexamethasone 5 mg). Finally, the metal Euclidean tube was withdrawn and the outer end of the epidural anesthesia catheter was wrapped with sterile gauze and fixed on the ipsilateral paranasal cheek, or fixed with silk suture on the ipsilateral inferior turbinate. The number of treatments can be extended to 5-10 times for severe cases, such as repeated tympanic membrane puncture, eustachian tube blowing or tympanotomy tube placement, etc., which are ineffective, and the duration of the disease is more than 6 months. Postoperative antibiotics are routinely applied to prevent infection, and oral treatment with Gineton, antihistamines and hormones, and topical nasal application of Dafenac and Cochlear spray. The efficacy of the treatment was judged after 3 months of postoperative follow-up. 1.3, efficacy evaluation criteria Cured: clinical symptoms such as tinnitus, stuffy ears and ear blockage disappeared, the hearing range of pure tone audiometric speech frequency improved to normal (0-25 dB), and the acoustic impedance graph was A-type; Improved: clinical symptoms such as tinnitus, stuffy ears and ear blockage reduced, the hearing range of pure tone audiometric speech frequency improved, but did not reach the normal range (25 dB-35 dB), and the acoustic impedance graph was As-type or C-type Invalid: no improvement in clinical symptoms, no improvement in the results of the tests. 1.4, Statistical method: χ2 test with R×C columnar data was used. The results were evaluated according to the efficacy criteria, 32 ears were cured (39.0), 38 ears were improved (46.3), and the total effective rate was 85.3. Only 2 cases of temporary vertigo occurred; the recorded pharyngeal orifice morphology was divided into five types: umbilical, circular, oval, slit, and atresia (see Figure 1-5). There were 35 cases with umbilical shape, 23 cases with slit shape, 13 cases with round shape, 9 cases with elliptical shape, and 2 cases with atresia shape. The relationship between the morphology of the pharyngeal orifice of the eustachian tube and the primary disease is shown in Table 1; the difference was statistically significant when comparing the efficacy of different disease courses, P<0.005, indicating that the disease course was related to the efficacy. 3, Discussion Nasal endoscopic eustachian tube placement is to insert an epidural anesthesia catheter through the natural channel of the eustachian tube to the tympanic ventricle, blow the eardrum through the catheter, inject the drug directly to the tympanic ventricle and the eustachian tube, and achieve the treatment purpose without damaging the eardrum, avoiding the occurrence of complications as much as possible, and having the characteristics of minimally invasive. The etiology of secretory otitis media is complex and has not yet been fully clarified. It is generally believed to be related to factors such as dysfunction of the eustachian tube, infection of the eustachian tube and middle ear tympanic chamber, and immune dysfunction, while eustachian tube obstruction and dysfunction are the basic etiology of the disease. In this group, the authors found that the disease was combined with a variety of complications of the nasal cavity and nasopharynx, including infections, allergic reactions, and tumors. From Table 1 we can also see that the primary causes of secretory otitis media are diverse, and the difference in the primary causes directly affects its outcome, and how the primary causes are managed will determine the prognosis of secretory otitis media. The different pathological processes of secretory otitis media result in different viscosity and nature of middle ear fluid and different degree of hearing loss, which are factors affecting the efficacy of nasal endoscopic eustachian tube placement. Table 2 shows that there is a significant difference in the cure rate among the three different courses of disease, indicating that patients with a short course of disease have a better outcome and can be kept in the tube for a relatively short period of time after placement, while those with a longer course of disease can be kept in the tube for as long as possible. Under the bright view of nasal endoscope, the surgeon must strictly perform aseptic operation and clean the pharyngeal opening of the eustachian tube before intubation to avoid bringing nasopharyngeal secretions into the tympanic chamber; the operation should be gentle to avoid damaging the mucosa of the pharyngeal opening of the eustachian tube and causing adhesions or stenosis, which may affect its efficacy. For cases with high jugular bulb or acute attack, CT or MRI should be carefully studied before surgery, and surgical indications should be carefully selected to avoid bleeding or other complications that may affect the efficacy. The appropriateness of the drug injected into the bullae is also one of the factors affecting the efficacy. If it belongs to non-bacterial infection, you can choose the preparation of diflucan injection 2ml plus a-chymotrypsin 5mg plus dexamethasone 5mg; if it belongs to those with incomplete control of bacterial infection, you can also choose the preparation of chloramphenicol 2ml plus a-chymotrypsin 5mg plus dexamethasone 5mg; if it belongs to pure mechanical compression, you can choose only the preparation of a-chymotrypsin 5mg plus dexamethasone 5mg . The injected drugs include diflucan with antibacterial and anti-inflammatory effects, clearing heat and detoxification, the mixture of antibiotics and dexamethasone can kill bacteria, and а-chymotrypsin has the effect of thinning middle ear secretions and promoting the elimination of effusion. We should use the appropriate treatment plan according to different tympanic lesions in order to improve their efficacy. Two cases of temporary vertigo occurred in our group, both in winter, which may be related to the temperature of the injected fluid. The morphology of the pharyngeal opening of the eustachian tube may affect the function of the eustachian tube, and poor opening of the pharyngeal opening of the eustachian tube is one of the reasons for the occurrence of secretory otitis media. We found that there are five types of pharyngo-pharyngeal orifice morphology through nasal endoscopy: umbilical, circular, oval, slit, and atretic. This may be due to the retrograde infection of the eustachian tube caused by inflammatory pus secretion, resulting in inflammatory reaction of the mucosa and lymphatic tissue of the eustachian tube; the close relationship between the fissure shape and inflammatory disease began to weaken, while the relationship with the tumor gradually strengthened, which may be related to the mechanical compression of the tumor; the round-like shape and the oval shape were not significantly associated with the original disease, but the number of cases of secretory otitis media was significantly higher in the round-like shape compared with the oval shape; only two cases of atresia occurred, both of which were patients with nasopharyngeal cancer after radiotherapy. This may be related to the fact that radiotherapy destroyed the "mucus cilia transport system" of the eustachian tube, and the inflammatory secretions were not easily discharged in the nasopharynx, which blocked the pharyngeal opening of the eustachian tube. This shows that there is a close relationship between the morphology of the pharyngeal orifice of the eustachian tube and secretory otitis media. The incidence of this disease in children is high and it is one of the common causes of hearing loss in children. Approximately 90% of children have had the disease before school age, but more than 50% of children have spontaneous remission within 3 months, 30% to 40% have recurrent episodes, and 5% to 10% have a persistent course; because the onset of the disease in children is mostly school age, and because surgery often requires general anesthesia; children tend to be seen in pediatrics, so not many children actually choose surgery. Hearing loss greater than 40 dB (at least moderate deafness) can have an impact on speech, language, and academic performance if sustained. Therefore, this method can be performed in appropriately selected children. If the disease lasts for more than 3 months, with persistent hearing loss or other signs and symptoms, and if the effects of chronic adenoiditis or tonsillitis are obvious, this method may be the first choice of treatment. The authors have not been able to measure the length and thickness of the eustachian tube, but are they also closely related to secretory otitis media? How can the poor structure of the eustachian tube be practically corrected so as to fundamentally improve the function of the eustachian tube and achieve a complete treatment of secretory otitis media? This is the direction we need to make further efforts to study in the future. It should be pointed out that the prognosis of secretory otitis media is also related to the regulation function of the eustachian tube, which is the basic defect of the function of the eustachian tube and an important reason for the persistence and recurrence of the disease. Therefore, how to improve and restore the regulating function of the eustachian tube is an important issue that we need to solve, which will be directly related to the long-term efficacy of secretory otitis media.