Chronic lacrimal dacryocystitis is a common disease in ophthalmology, mostly caused by the retention of tears in the lacrimal sac after the narrowing or obstruction of the nasolacrimal duct, accompanied by bacterial infection. In recent years, some new therapies such as lacrimal stents and lacrimal endoscopy have emerged on behalf of medication and minimally invasive surgical treatment, and the current status and progress of these therapies will be reviewed in this paper. Chronic lacrimal dacryocystitis is the most common of the lacrimal sac lesions, which occurs in adult women and middle-aged and elderly people, mostly secondary to the narrowing or obstruction of the nasolacrimal ducts, with the retention of tears in the lacrimal sac, caused by bacterial infection, and in severe cases can form septic cysts. The main symptom of this disease is tearing, if not treated, the patient will have a lifetime of tears, which brings great inconvenience and pain to life and work. In addition, chronic lacrimal sac infection, as a potential source of infection in the eye, can easily lead to septic infection and even loss of visual function once trauma or internal eye surgery is performed. In the past, the main treatment was external surgery, but in recent years, with the improvement of people’s health requirements and medical technology, many new treatments have emerged. In this article, we will review traditional surgery, minimally invasive surgery and some non-surgical therapies, and focus on minimally invasive surgery, which is an emerging hot treatment method in recent years. Drug therapy is the basis for the treatment of chronic dacryocystitis, and the main drugs used in clinical practice are antibacterial drugs, drugs to prevent adhesions to the lacrimal mucosa, drugs to promote the repair of lacrimal mucosa tissues and some Chinese medicinal preparations with comprehensive pharmacological effects. 1, antibacterial drugs: chronic dacryocystitis as an inflammatory disease, sterilization antibacterial is the focus of treatment, the use of antibacterial drugs should pay attention to the pathogenic bacteria and their drug sensitivity. Lu Xi et al [1] showed that 76 pathogenic bacteria were positive in 104 patients, and 22 pathogenic bacteria were detected, including 21 strains of coagulase-negative Staphylococcus (20.2%), 16 strains of Streptococcus gramineus (15.4%), 7 strains of Pseudomonas aeruginosa (6.7%), 6 strains of Staphylococcus aureus (5.8%), and 1 strain of Pseudomonas quinquefaciens. The detected pathogens were all less sensitive to chloramphenicol, and the detected cocci were 100% sensitive to vancomycin. Among several common pathogenic bacteria, the sensitivity rates to ofloxacin and cefazolin and gentamicin were high. According to a foreign report in 2005, Pseudomonas aeruginosa was 100% sensitive to ceftazidime and 86% sensitive to ciprofloxacin, while its sensitivity to aminophecillin was only 20%. Since 35.3%~54.8% of anaerobic bacteria were detected in the tear sac secretions of patients with dacryocystitis, some experts advocate the addition of metronidazole to flush the tear duct. 2.Drugs to prevent adhesion of lacrimal mucosa: dexamethasone, sodium hyaluronate, antibiotic eye ointment, Mepore moist burn cream, Sugao Jet Therapy eye ointment, mitomycin, 5-fluorouracil. 3.Drugs to promote tear mucosa tissue repair: epithelial growth factor, recombinant bovine basic fibroblast growth factor (trade name: Bevosol) eye drops. 4, Chinese medicine preparation: mainly to anti-inflammatory detoxification, detoxification and muscle production, including Qianjin Qin rinse solution, compound a branch of artemisia rinse solution. It should be noted that the correct way to give chronic dacryocystitis patients eye drops is different from ordinary patients, should be “a wash two press three dial four points”, a wash that is to wash hands, two press that is to use cotton swabs to press the tear sac area, so that the pus and other secretions stored in the corner of the eye out, to remove pathogenic bacteria, to prevent infection of the eye, three dial that is to dial the lower eyelid, four points is about to ophthalmic medicine is dabbed into the junction of the lower eyelid and the eyeball, so that it passes smoothly through the lacrimal duct and nasolacrimal duct and plays a therapeutic role [7]. Tear duct exploration, dilation and irrigation Tear duct exploration and irrigation is both an examination and a treatment. For lacrimal ducts that have been explored, regular dilation is required to avoid reoccurrence of obstruction. Only a small percentage of patients can be cured, and the combination of lacrimal stenting is currently advocated. The main point of lacrimal duct probing is to be gentle and not to force the lacrimal duct forward when it encounters resistance. If the probe encounters resistance when it leaves the vicinity of the lacrimal duct, attention should be paid to adjusting the position and tension of the eyelid to prevent the lacrimal duct from folding and creating resistance. At present, endoscopic lacrimal duct exploration has been carried out: Wallace et al. performed endoscopic lacrimal duct exploration in 67 children (87 eyes), all of which were successful, and 55.6% of the children recovered their lacrimal duct function. Massage therapy in the lacrimal sac area is mainly used for nasolacrimal duct inferior orifice obstruction in newborns. It should be noted that the medical staff must instruct the child’s family to massage according to the correct technique, and instruct the patient to review on a regular basis, if there is local redness, swelling, pain and other conditions such as acute lacrimal sac inflammation episodes should be timely follow-up. Radioactive probe internal irradiation treatment The treatment of lacrimal stenosis and prevention of restenosis with built-in radiation from a radioactive probe is a new technique developed in recent years. The literature confirms that radiation absorbed at a dose of 10 Gy is sufficient to inhibit gene transcription in proliferating cells or directly disrupt the integrity of cell membranes. The thickness of the proliferating tissue at the lacrimal stenosis is usually 2-4 mm, and the results of the study show that about 85% of the absorbed dose is completely released when the radioactive probe rays reach the surrounding tissue 5-6 mm, giving sufficient therapeutic dose to the proliferating tissue at the stenosis in a short period of time. At the same time, the shape of the radioactive lacrimal probe used is basically the same as that of the common lacrimal access tube, which has the effect of mechanical access and radioactive treatment, thus not only treating the lacrimal stenosis but also preventing the occurrence of lacrimal restenosis. Surgical treatment (a) transcutaneous nasal lacrimal sac anastomosis Transcutaneous lacrimal sac nasal anastomosis is a classic procedure for treating nasolacrimal duct obstruction and chronic dacryocystitis, in which the lacrimal sac and nasal mucosa are incised with direct sutures to allow tears and secretions to flow directly from the lacrimal sac into the nasal cavity, constituting a new lacrimal duct. At present, transnasal endoscopic surgery has fewer complications, but the efficacy of percutaneous conventional surgery is certain, and its results are still better than those of transnasal endoscopic surgery. In recent years, there are some improvements in nasal lacrimal sac anastomosis surgery: (1) the anastomotic anterior flap is sutured and suspended in the orbicularis oculi muscle, which can prevent the recurrence caused by the collapse of the anterior flap; (2) the simultaneous combination of the application of nasal endoscopic observation and treatment of the anastomosis has improved the success rate of the surgery. Due to the large surgical trauma and facial scarring, it is difficult to be accepted by patients, and other therapies are gradually emerging, but for chronic dacryocystitis caused by bony obstruction of the nasolacrimal duct, it is still a better procedure for effective treatment. (B) Nasal endoscopic laser lacrimal sac nasal anastomosis Compared with traditional surgery, it has the advantages of less surgical damage, no surgical scar on the face after surgery, and easy acceptance by patients. Javate et al. compared the success rate of this procedure with that of the traditional procedure and concluded that the difference was not statistically significant and that this procedure had many advantages such as fewer complications, less injury, wider indications, simpler and faster recovery, less pain and no facial scarring. The disadvantages of this procedure are small stoma, high recurrence rate, difficult to form physiological curvature, expensive instruments and equipment, and certain controversies in terms of efficacy. Some reports show that the effect of nasal endoscopic lacrimal sac rhinoplasty is inferior to that of traditional external nasal lacrimal sac rhinoplasty, mainly because the bone removed by nasal endoscopic lacrimal sac rhinoplasty is not sufficient, resulting in poor postoperative tear drainage. (iii) Laser lacrimal ductoplasty The main method of this procedure is to apply the blasting effect and thermal effect of laser to open up the obstruction site, which is suitable for obstruction of any part of the membranous lacrimal duct, and is especially effective in treating obstruction of the lacrimal duct and common lacrimal duct. The accuracy and success rate of lacrimal laser treatment can be improved by performing it under lacrimal endoscopy. Because of the low cure rate of laser treatment alone, the combination of lacrimal stenting is currently advocated. (D) lacrimal stent or artificial lacrimal implantation At present, the lacrimal stents and artificial tear ducts used at home and abroad mainly include nickel-titanium alloy lacrimal stent, artificial gold nasolacrimal duct, stainless steel nasolacrimal duct stent, Y-shaped silicone tube, polyurethane lacrimal stent, double lacrimal duct implantation silicone artificial tear duct, nasolacrimal duct balloon type stent, C-type tube, U-type tube, U-type tube, lacrimal duct stent, lacrimal duct stent, nasolacrimal duct stent. C-tube, U-tube, catheter for epidural anesthesia and various homemade stents, among which the more used in China are the “Y”-shaped silicone tube and double tear duct implantable silicone artificial tear tube. For different types of stents and the same stent in different types of dacryocystitis, the timing of removal is still controversial, the general principle is that metal stents are generally left for a long time, unless the occurrence of lacrimal reobstruction before they need to be removed, most other lacrimal stents and artificial tear ducts can generally be considered for removal after 1 to 3 months of placement, if the bone stenosis is serious, the placement time can be extended appropriately, but generally not more than 1 year. The development of permanently retained artificial tear ducts or lacrimal stents will be a hot spot for future research. (E) lacrimal endoscope The lacrimal endoscope makes people get the morphological image of lacrimal tissues directly for the first time, and also makes the laser lacrimal surgery under direct vision possible. In foreign countries, endoscopy has been used in many hospitals for the treatment of lacrimal tract diseases, and related research has made great progress. It was reported that lacrimal endoscopy could see the condition of the lacrimal tract lesion site more accurately than lacrimal ductography, thus considering lacrimal endoscopy as a better technique for lacrimal tract disease examination, which is expected to replace lacrimal ductography; Maier et al. first used a miniature electric drill for the treatment of lacrimal tract disease under lacrimal endoscopy, and after the obstruction site was seen under lacrimal endoscopy, the obstruction was removed with a miniature electric drill, and then a silicone tube was placed in the lacrimal tract. The surgical efficacy was greatly improved; Haefliger and Pifaretti reported the treatment of lacrimal tract disease under lacrimal endoscopy with different sizes of loop drills; Klaus et al. treated 19 patients with upper lacrimal tract obstruction with Er:YAG laser under lacrimal endoscopy and left a silicone tube in place after the procedure with satisfactory results at 14 months of follow-up. Compared with the traditional external lacrimal sac nasal anastomosis, lacrimal endoscopy also has several advantages: (1) no facial skin incision and resulting scar; (2) little tissue damage and fast postoperative recovery; (3) no separation of the orbicularis oculi, periosteum and lacrimal sac, small incision of the lacrimal sac, and less impact on the lacrimal pump function in the lacrimal sac and other areas; (4) no damage to the tear dots and lacrimal ducts, preserving the The siphoning effect of the lacrimal duct is preserved; (5) the postoperative recovery is fast and the efficacy is comparable to that of traditional surgery; (6) the operation time is short; (7) other lesions in the lacrimal duct can be detected at the same time. The emergence of lacrimal endoscopy has enriched the diagnosis and treatment techniques of lacrimal tract diseases, which can effectively observe the internal structure of the lacrimal tract and effectively treat the lesions simultaneously to avoid unnecessary damage to the maximum extent, and can provide a variety of adjuvant treatments, which have been used in developed countries to some extent, but its relatively expensive and complicated operation has limited its development and popularity in China. After years of research and practice, the treatment of chronic dacryocystitis has developed into non-surgical therapies including drug therapy, lacrimal dilation and irrigation, lacrimal sac massage, radioactive probe internal irradiation, traditional surgical therapies represented by percutaneous nasal lacrimal sac anastomosis, as well as recent developments including nasal endoscopic laser nasal lacrimal sac anastomosis, laser lacrimal ductoplasty, lacrimal stent or artificial lacrimal duct implantation, lacrimal endoscopy and other new minimally invasive therapies. All methods have their superiority and indications, and the results of their clinical application still need further research and evaluation.