Nowadays, the number of patients who visit outpatient clinics for snoring at night is gradually increasing, so we hope that reading this article will bring benefits to the corresponding patients. Snoring can be simply divided into simple snoring (i.e. snoring loudly but without apnea or hypoventilation) and sleep apnea syndrome (defined as apnea and hypoventilation caused by collapsed obstruction of the upper airway during sleep, usually accompanied by snoring, sleep structure disorder, frequent decrease in blood oxygen saturation, daytime drowsiness, inattention and other conditions, and may lead to multi-organ and multi-system damage), and clinical The latter is the main concern. The following is the outpatient consultation process: 1. Physical examination by the outpatient physician, including nasal cavity, oropharynx, tongue, hypopharynx and larynx for narrowing, overweight and obesity. 2. Appointment for sleep monitoring, which is usually done overnight in the hospital to monitor sleep status. The following appointment sheet is the precautions to be taken before performing the monitoring: 3. Before monitoring, the health care provider needs to ask about the medical history, fill out some forms and general vital sign measurements. Common knowledge: Sleep monitoring (PSG) mainly monitors the following parameters and is the gold standard for diagnosing OSAHS when monitoring photos 4. If sleep apnea hypoventilation syndrome is diagnosed and surgical treatment is considered, some positioning tests need to be performed to determine the site and scope of surgery, commonly used tests are as follows: 1) Sleep monitoring and obstruction localization system (ApneaGraph, AG200), which can determine the obstruction site in soft palate or tongue plane. The box into which the data are collected is a lateral view of the body into which the leads are placed. 2) Tomography 3) CT of the upper airway: the airway is reconstructed and measurements are taken to determine the obstruction, soft tissue thickness, airway width and other parameters. 4) Fiberoptic laryngoscopy can dynamically determine the site of obstruction, as shown below to show whether there is stenosis in the plane of the tongue root. Each of these tests has some drawbacks, but the combined assessment of the above tests can lead to a final diagnosis and a reasonable treatment plan.