I. Lacrimal duct obstruction or stenosis The beginning of the lacrimal duct (lacrimal puncta, lacrimal duct, common lacrimal duct) is narrow and thin, superficially located, and adjacent to the conjunctival sac, which is susceptible to obstruction by inflammation and trauma. The lower end of the nasolacrimal duct is also an anatomically narrow section, which is easily obstructed by nasal lesions. [Etiology] 1. Tear duct ectropion, the tear duct cannot contact the tear lake. The main causes are age-related eyelid laxity or lid ectropion. 2, tear dots abnormalities, including narrowing, occlusion or lack of tear dots. 3, obstruction or narrowing of the lacrimal duct to the nasolacrimal duct, including congenital atresia, inflammation, tumors, stones, trauma, foreign body drug toxicity and other factors caused by the tear duct structure or functional insufficiency, resulting in the inability to drain tears. 4, other causes, such as nasal obstruction, etc. Clinical manifestations】 The main symptom of tear duct obstruction or narrowing is tear overflow. Tear overflow can be seen in infants. The tear draining part is formed gradually during embryonic growth, among which the nasolacrimal duct is formed the latest, often there is still a mucosal fold (Hasner flap) partially or completely covering the opening of the nasolacrimal duct at the lower end of the nasolacrimal duct by the time of birth, which can usually open on its own within a few months of birth. Incomplete development of the lower end of the nasolacrimal duct, incomplete “canalization”, or obstruction by membranous material is the main cause of tear flow in infants. If there is secondary infection of the lacrimal sac, mucopurulent discharge may occur, resulting in neonatal dacryocystitis. In middle-aged and older adults, lacrimal overflow is mostly associated with functional or organic lacrimal obstruction, and symptoms worsen in windy or cold climates. In a significant number of adults, lacrimal overflow is not associated with significant lacrimal obstruction and the lacrimal ducts are flushed. Tear overflow is a functional retention, mainly due to relaxation of the orbicularis oculi muscle, weakening or loss of the tear pump, impaired tear drainage, and tear overflow. This is functional tear overflow. Tear overflow caused by the above listed causes of tear duct obstruction or narrowing are all organic tear overflow. Tear overflow can cause discomfort and cosmetic defects. Chronic tear maceration can cause chronic irritant conjunctivitis, eczematous dermatitis of the lower lids and cheeks. The patient is constantly wiping the tears away, and the long-term effect can lead to lower lid ectropion, which can aggravate tear overflow symptoms. Because organic lacrimal obstruction or stenosis can occur in any part of the lacrimal duct, it is important to determine the site of obstruction for the choice of treatment plan. (1) Dye test: Put a drop of 2% sodium fluorescein solution into the conjunctival sac of both eyes, observe and compare the fading of fluorescein in the tear film of both eyes after 5 minutes, if more fluorescein is retained in one eye, it indicates that the eye may have relative lacrimal obstruction; or wipe the lower nasal tract with a wet cotton swab after 2 minutes of 2% sodium fluorescein drop, if the swab is greenish-yellow, it indicates that the lacrimal tract is open or not completely obstructed. or no complete obstruction. (2) Tear duct irrigation (video) Tear duct irrigation can often reveal the site of tear duct obstruction. A blunt round needle is used to inject saline from the lacrimal punctum to determine the presence and location of obstruction based on the flow of the flushing fluid. At the same time, there is mucopurulent discharge, for nasolacrimal duct obstruction combined with chronic dacryocystitis. (3) lacrimal tract exploration, diagnostic lacrimal tract exploration helps to confirm the site of upper lacrimal tract (lacrimal dots, lacrimal ducts, lacrimal sacs) obstruction, therapeutic lacrimal tract exploration is mainly used for infants and children with lacrimal tract obstruction, for adults with nasolacrimal duct obstruction, lacrimal tract exploration mostly cannot play a radical effect. (3) X-ray iodine oil imaging to show the size of the lacrimal sac and the site of lacrimal duct obstruction. Treatment】 1, infants with lacrimal duct obstruction or narrowing can try regular finger pressure on the lacrimal sac area, from the lower lid orbital line between the medial and the eye downward pressure, compression several times after the point antibiotic eye solution, 3 to 4 times a day, adhere to several weeks, can prompt the lower end of the nasolacrimal duct open. Most children can heal spontaneously as the opening of the nasolacrimal duct develops, or heal after compression. If conservative treatment is ineffective, lacrimal duct exploratory surgery can be considered after the age of half a year. 2, functional tear overflow can try zinc sulfate and epinephrine solution to contract the tear sac mucosa. 3, tear dots are narrowed, occluded or missing if a tear duct dilator or tear duct probe is available. 4. For lid ectropion with abnormal tear dots, a horizontal oval conjunctiva and subconjunctival connective tissue can be removed below the tear dots and shortened with horizontal conjunctival sutures to correct the lid ectropion and reset the tear dots. If the patient has lax eyelids, horizontal eyelid shortening can be performed at the same time. In addition, electrocautery can be performed to electrocauterize the conjunctiva below the lacrimal dots, and the lacrimal dots can be reset with the help of scar contraction after surgery. 5. Tear duct obstruction can be treated with lacrimal silicone tube placement. In recent years, laser treatment of lacrimal duct obstruction has been carried out, through the probe guide light fiber to the site of obstruction, the use of pulsed YAG laser vaporization effect to open the obstruction, postoperative with intubation or placement of wire, can improve the efficacy. For the obstruction of the common lacrimal duct, conjunctival – lacrimal sac nasal anastomosis can be used to establish an artificial tear duct with Pyrex tube or own vein to drain the tear directly from the conjunctival sac to the lacrimal sac or to the nasal cavity. Acute dacryocystitis occurs mostly on the basis of chronic dacryocystitis and is related to the virulence of the invading bacteria or the lowering of the body’s resistance, the most common causative organisms being Staphylococcus aureus or Streptococcus haemolyticus. The most common causative agent is Staphylococcus aureus or Streptococcus hemolyticus. Clinical manifestations】 The affected eye is congested, lacrimation, local skin of the lacrimal sac area is red, hard, painful, pressure pain is obvious, inflammation can extend to the eyelids, nasal root and cheeks, and can even cause orbital cellulitis, in severe cases can appear chills, fever and other general discomfort. After a few days, the redness is limited and pus spots appear. The abscess can penetrate the skin, the pus is discharged and the inflammation is reduced. However, sometimes a tear sac fistula can be formed, which is not healed for a long time, and the tears spill through the fistula for a long time. Treatment】 Early feasible local hot compresses, systemic and local antibiotics in adequate amounts to control inflammation. During the inflammatory phase, tear duct probing or tear duct flushing should not be used to avoid spreading the infection and causing orbital cellulitis. If the inflammation is not controlled and an abscess is formed, it should be incised and drained, rubber drainage strips should be placed, and the wound should be healed and the inflammation should be treated as chronic dacryocystitis after it has completely subsided. Chronic dacryocystitis (chronic dacryocystitis) is the most common of the lacrimal sac lesions, mostly secondary to narrowing or obstruction of the nasolacrimal ducts, tear retention within the lacrimal sac, accompanied by bacterial infection caused by unilateral onset. The common causative organisms are Streptococcus pneumoniae and Candida albicans, but mixed infections do not usually occur, and smear staining of the secretions from the lacrimal puncta can identify the pathogenic microorganisms. The disease is most often seen in middle-aged and older women. The onset of chronic lacrimal sacculitis is related to trachoma, lacrimal trauma, rhinitis, nasal septum deviation, inferior turbinate hypertrophy and other factors. Clinical manifestations】 The main symptom is tear overflow. The examination reveals conjunctival congestion, eczema on the skin of the lower lid, and mucus or mucopurulent secretions flowing from the tear dots when the tear sac area is squeezed with a finger. When the lacrimal duct is flushed, the flushing fluid returns from the upper and lower lacrimal dots, along with mucopurulent secretions. Due to the large amount of storage of secretions, the tear sac expands and can form a mucous cyst of the lacrimal sac. Chronic dacryocystitis is an infected lesion in the eye. Because there is often mucus or pus flowing back into the conjunctival sac, the conjunctival sac is in a long-term bacterial state. In case of ocular trauma or internal eye surgery, it is easy to cause septic infection, leading to bacterial corneal ulcer or septic endophthalmitis. Therefore, the potential threat to the eye posed by chronic lacrimal sac infection should be given high priority, especially before internal eye surgery, and the lacrimal sac infection must be treated first. Treatment】 Medication Antibiotic eye drops can be used 4 to 6 times a day. The secretions should be squeezed out before the drops are applied, or antibiotic solution can be injected after the tear duct is flushed. Medication can only temporarily reduce the symptoms. Surgery Opening the blocked nasolacrimal duct is the key to treating chronic dacryocystitis. A common procedure is the lacrimal sac nasal anastomosis, in which the lacrimal sac is anastomosed to the nasal mucosa through a bony hole, allowing tears to flow directly into the middle nasal passage through the anastomosis. Nasal endoscopic nasal dacryocystostomy or nasolacrimal duct stenting can also be performed to eliminate tear overflow and cure chronic dacryocystitis. When anastomosis or stoma cannot be performed, such as in elderly patients, lacrimal sac removal may be considered to remove the lesion, but postoperative tear overflow symptoms persist.