Chronic dacryocystitis is a relatively common disease in ophthalmology. It often manifests as discomfort such as tearing and pus flow, but because there are usually no other discomfort symptoms such as pain, skin redness or swelling, and it does not affect vision, it is easily overlooked and many patients do not receive timely treatment. In fact, this can lay a greater hidden danger, because the pus-filled tear sac is like a reservoir of bacteria, which can infect the eye at any time and may cause irreparable damage. In addition, chronic dacryocystitis is a threat to eye surgery, such as glaucoma surgery, cataract surgery, and myopia surgery, and can cause serious post-operative infections, and such patients must have their chronic dacryocystitis cured before they can have these surgeries. Therefore, when the phenomenon of pus flowing from the corner of the eye occurs, it should not be taken lightly and should be treated as early as possible. Treatment of chronic lacrimal sacculitis 1. For patients who have been ill for a short time and whose nasolacrimal ducts are not completely blocked, antibiotic eye drops should be ordered and nasal diseases should be treated at the same time. 2.If the nasolacrimal duct is only partially narrowed, try lacrimal tract exploration or nasolacrimal duct intubation. 3, tear point and lacrimal duct normal, can be lacrimal sac nasal anastomosis. 4.If the lacrimal sac is excessively narrow, or the patient is old and frail, or if there is a serious scar after the injury, it is feasible to remove the lacrimal sac. Traditional lacrimal sac resection and nasal outer diameter lacrimal sac nasal anastomosis are classic surgeries for ophthalmologists to treat chronic dacryocystitis, but there are obvious shortcomings. In recent years, with the establishment and development of nasal endoscopy and nasal-ocular related surgery, endonasal endoscopic endonasal dacryocystorhinostomy for chronic dacryocystitis has achieved better clinical efficacy and provided a new way for the surgical treatment of chronic dacryocystitis. Since the lacrimal sac is anatomically separated from the nasal cavity by only two layers, namely the nasal mucosa and the bony lacrimal sac fossa, endonasal endoscopic lacrimal sac nasal anastomosis has the advantages of less injury, accurate positioning, simple operation, no facial scar and less complications than the traditional nasal OD surgery; it can deal with nasal cavity and sinus lesions at the same time, which is incomparable to the previous nasal OD surgery, and is a more ideal surgical treatment method for chronic lacrimal sacitis at present.