Mr. Shen has been suffering from severe thyroid-related proptosis for 40 years, with his two eyeballs protruding like light bulbs, and he has been going to major hospitals in Beijing, Shanghai and Guangzhou for treatment for 40 years. Doctors believed that the protrusion of the patient’s eyeballs was related to hyperthyroidism. However, after the hyperthyroidism was cured, the protruding eyeballs did not get better and even got worse. Many well-known doctors said that the protruding eyeballs would not return. Recently, the ophthalmology hospital adopted today’s advanced endoscopic technology to perform a bony orbital decompression surgery via the nasal cavity, and the patient’s bilateral eyeballs basically receded to normal. Thyroid-associated proptosis is relatively common and accounts for the largest number of orbital disorders in adults. It is an autoimmune disease with some similarity in pathogenesis to thyroid dysfunction, with approximately 50% of patients associated with hyperthyroidism. It can affect any tissue of the eye, showing eyelid recession, eye protrusion, eye movement disorders, corneal exposure lesions, and even increased intraocular pressure and progressive vision loss. Thyroid-associated proptosis is one of the most difficult diseases in the field of ophthalmology. It is a multi-tissue disease and is extremely complex. Currently, many doctors have a superficial understanding of this disease and even recommend abandoning treatment, resulting in some patients eventually losing their eyesight due to corneal ulcers or optic nerve atrophy. The mechanism of eye protrusion due to thyroid-related ophthalmopathy lies in the overgrowth and hypertrophy of intraorbital tissues, especially fat or extraocular muscles. Although there are various treatments such as high-dose hormone shock therapy, radiation therapy and surgery, orbital decompression surgery is increasingly adopted by doctors because of the toxic side effects and uncertainty of the efficacy of hormone and radiation therapy. At present, most hospitals in China adopt orbital bony decompression surgery or partial fat removal via facial skin pathway or conjunctival pathway, but there are disadvantages such as large trauma, facial skin scar, heavy postoperative reaction, many complications and unsatisfactory efficacy, especially for some patients with reduced visual function, the effect of traditional treatment methods is very limited. The endoscopic transnasal pathway orbital lateral wall and inferior wall bony orbital decompression surgery combined with partial orbital fat removal carried out at the Optometry Hospital has the potential to provide a relatively ideal treatment for such patients and is the first of its kind in China. Compared with traditional methods, this procedure has the advantages of adequate decompression, minimal trauma, no facial skin scarring, light postoperative reaction and quick recovery, safety, and stable and reliable long-term results. So far, the technique has benefited more than 30 patients, with stable and reliable surgical results and no significant complications. After examination by the optometric hospital, Mr. Shen had a protrusion of more than 30mm in both eyes, at least 18-20mm more than normal, and high pressure in both eyes, making him a severe proptosis. Such a patient with thyroid-related proptosis of more than 30mm is extremely rare in China, and the surgery was extremely difficult. After careful preoperative design and intraoperative management, endoscopic bony orbital decompression was performed in both eyes, and a combined decompression of the inferior extraorbital wall was performed in the right eye because of the actual protrusion of 32 mm. The operation went smoothly without complications such as intraorbital infection, hemorrhage, or significant displacement of the eye.