The pharynx is connected to the nasal cavity above and the esophagus and trachea below, and is the common channel for breathing and digestion. It has important physiological functions such as breathing, swallowing, speech formation, defense and protection, and immunity, which are directly related to survival and affect the quality of life. People often use the term “throat” to describe the important position and role of the throat in the human body. At the same time, the pharynx is an important channel for the body to communicate with the outside world and exchange gases and food. In summary, the anatomical and physiological characteristics of the pharynx are “connecting up and down, communicating inside and outside, common channel”. Therefore, the pharynx is easily affected by changes in the external environment and diseases of neighboring organs, as well as by the immune function and defense ability of the body. The combined effect of these factors makes the incidence of pharyngeal diseases high, and to a certain extent reflects the overall functional status of the human body. Chronic pharyngitis is the most common disease of the pharynx. However, the diagnosis of chronic pharyngitis currently lacks uniform criteria and is highly arbitrary. Chronic pharyngitis refers to diffuse chronic inflammation of the pharyngeal mucosa, submucosa, and lymphatic tissue. It is classified as simple, hypertrophic, or atrophic. Many local and systemic lesions can present with symptoms of pharyngeal discomfort, so careful screening is needed to avoid misdiagnosis and missed diagnoses. The main differential diagnoses of chronic pharyngitis are discussed. (A) Reflux pharyngitis Reflux pharyngitis (LPR) is a disease caused by reflux of gastric contents into the pharynx; the pathogenesis is mainly due to the dysfunction of the upper and lower esophageal sphincters and the weakened contouring ability of the esophagus, which causes gastric contents to reflux into the pharynx and cause injury. The main cause of damage to the pharynx from gastric contents is direct damage to the mucosa by gastric acid and pepsin. In addition, stimulation of the larynx, vagal reflex, bronchoconstriction, coughing and repeated throat clearing also damage the laryngeal mucosa. There are no accurate statistics on the incidence of reflux laryngitis, but it accounts for a significant proportion of patients with throat discomfort, and its incidence has been underestimated due to lack of awareness of the disease. The most common symptoms of reflux pharyngitis are hoarseness and dysphonia, others are chronic cough, foreign body sensation in the throat, habitual throat clearing, difficulty in swallowing, and only a few patients have heartburn and acid reflux. Uncommon symptoms include: laryngospasm, arytenoid cartilage fixation, laryngeal stenosis and tumors, and acoustic prominence granuloma. The most typical signs on fiberoptic laryngoscopy are posterior joint edema and erythema. In addition, there are pseudo-vocal fold sulcus, laryngeal ventricular occlusion, laryngeal mucosa erythema and congestion, vocal fold edema, posterior joint hypertrophy, diffuse laryngeal edema, granuloma, and laryngeal mucosal thickening. (b) Stromal overgrowth The stromal process is an elongated cylindrical bone in front of the stromal foramen at the base of the temporal bone. There are several muscles and ligaments attached to it, and there are linguopharyngeal nerve, collateral nerve, vagus nerve and internal and external carotid artery nearby. If the stem develops too long or the stem ligament ossifies, the symptoms may occur when the surrounding muscles, ligaments, nerves or blood vessels are compressed. The common symptoms are ① pharyngeal pain, often one-sided stabbing pain, pulling pain, which may radiate to the neck or ear, or shoulder and back pain. (2) Foreign body sensation in the pharynx, mostly one-sided, aggravated by swallowing, talking, turning the head or at night. ③Carotid artery compression symptoms, irritation of the internal carotid artery, radiating to the top of the head and eye area, and irritation of the external carotid artery, radiating to the same side of the face. When complaints of pharyngeal foreign body sensation and sore throat are more fixed and radiating to the head and ears, the possibility of an overgrown stalk should be thought of. Palpation of the tonsillar fossa may palpate hard strips or sharp ends of the stalk in the tonsillar fossa. Positive and lateral views of the caudate and caudate tomograms can help in the diagnosis. The average length of the normal stalk is 2.5 cm, and the normal range of x-ray length is 2.5-3.0 cm. Treatment is by stalk osteotomy, which is often done by intraoral approach. (C) hyoid bone syndrome Hyoid bone syndrome refers to pain in one side of the neck during swallowing, which may radiate to the ear, face and jaw, etc. It may be accompanied by foreign body sensation and discomfort in the pharynx and tenderness at the large horn of the hyoid bone on the affected side. The etiology is due to degeneration of the tendons attached to the hyoid muscles or the intermediate tendons of the bicipital muscles, tenosynovitis, synovial bursitis or calcification of the osteophytes of the greater horn of the hyoid bone. Diagnostic points: ① pain under the face and upper neck area and radiating to the adjacent areas, or accompanied by foreign body sensation and discomfort in the pharynx, swallowing obstruction, etc. ② obvious tenderness at the large horn of the hyoid bone on one side ③ exclude other pathologies such as excessive stem protrusion, cervical spine or esophagus. Treatment can be localized with steroid hormone and local anesthetic mixture, such as methylprednisolone 40mg/ml plus 1% lidocaine 1ml local injection. In addition, physical therapy can be used. If the conservative effect is not good, hyoidectomy with large horn is performed. (D) Pharyngeal occupying lesions Benign and malignant tumors of the nasopharynx, oropharynx and laryngopharynx can show symptoms such as foreign body sensation and discomfort in the pharynx, therefore, detailed specialist examination is essential to avoid misdiagnosis. Detailed examination of all parts of the ear, nose, pharynx and larynx and fiberoptic laryngoscopy are necessary. Tumors in the parapharyngeal space have insidious symptoms and are often detected only after the tumor volume increases. The pharyngeal occupancy may also show corresponding nerve and blood vessel compression according to the location and scope of the lesion. In conclusion, only through a detailed medical history, careful specialist examination, correct understanding of the relevant diseases, and the necessary auxiliary examinations can the correct diagnosis and differential diagnosis of chronic pharyngitis be made.