Diseases of the lacrimal secretion system include lacrimal gland inflammation and lacrimal gland tumors. Acute dacryoadenitis is a rare clinical condition, usually unilateral, mainly in children, and is often complicated by measles, mumps and influenza. The pathogenesis is mostly due to bacterial and viral infections, with Staphylococcus aureus or Neisseria gonorrhoeae being common. The route of infection can be direct spread of purulent inflammation of the eyelid, conjunctiva, orbit or face, metastasis of distant purulent lesions, or from systemic infections. Clinical manifestations] Acute lacrimal glanditis may involve the lid lobe or orbital lobe of the lacrimal gland separately or simultaneously, manifesting as localized swelling and pain over the orbit, “S”-shaped bending and deformation of the upper lid edema, and enlarged lymph nodes in front of the ear. On palpation, a mass can be found with pressure pain, and the conjunctiva is congested and edematous with mucous secretions. When the upper lid is lifted, the lacrimal gland tissue is seen to be congested and enlarged. Acute lacrimal glanditis is usually short-lived and may resolve with treatment or may become subacute or chronic. Abscesses may also form. Treatment】Treatment is based on the cause and symptoms. For bacterial and viral infections, systemic antibiotics or antiviral drugs should be applied, and local hot compresses should be applied. When an abscess is formed, it should be drained promptly by incision, and lid lacrimal adenitis can be drained by conjunctival incision, while orbital lacrimal abscess can be drained by skin incision. Chronic dacryoadenitis is a proliferative inflammatory disease with a slow progression, and the lesions are mostly bilateral. Etiology】 Immune reaction is the main cause, but it can also be trachomatous and tuberculous, the latter mostly by hematogenous dissemination. In addition, sarcoidosis and Sjogren’s syndrome can involve the lacrimal gland and manifest as chronic lacrimal gland inflammation. Benign lymphocytic lesions (Mikulicz syndrome), lymphoma and leukemia can involve the lacrimal gland, and biopsy can identify the cause. Clinical manifestations】The lacrimal gland is enlarged, usually without pain, and may be accompanied by ptosis, a hard mass may be palpated under the external superior orbital rim, but mostly without pressure pain, the eye may be inferiorly deviated inward, and diplopia may be present when looking upward or outward, but protrusion of the eye is rare. 【Treatment】Treatment for the cause or primary disease. Syringomyelia and Mikulicz syndrome are effective with local or systemic glucocorticoids. Sjogren’s syndrome can be treated with immunosuppression and anti-inflammatory therapy, supplemented with artificial tear drops. Tumors of the lacrimal gland mainly refer to tumors originating from the lacrimal gland, which account for the first place of orbital occupational lesions. 50% are inflammatory pseudotumors or lymphoma, 50% are tumors of epithelial origin, and most originate from the orbital lobe of the lacrimal gland. Of the primary epithelial tumors, 50% are benign (pleomorphic adenomas) and 50% are malignant. Of the malignant lacrimal gland tumors, 50% are cystic adenocarcinomas, 25% are malignant mixed tumors, and the remaining 25% are adenocarcinomas. Pleomorphic adenomas of the lacrimal gland are also known as mixed lacrimal gland tumors. Histologically, pleomorphic adenomas of the lacrimal gland contain a double layer of glandular epithelium and abnormal stromal components such as fat, fiber, and cartilage tissue, hence the name “pleomorphic adenoma”. Clinical manifestations】 Mostly seen in young adults, slightly more in males, generally unilateral involvement, slow onset, manifested as a painless mass over the orbit. The tumor is usually unilateral and has a slow onset. The patient may have no diplopia due to the slow growth of the tumor. CT scan clearly shows a high-density mass and compression bone depression of the lacrimal fossa. In elderly patients, malignant mixed tumor should be considered, which is characterized by rapid tumor growth and obvious bone destruction. Treatment】 Surgical excision. As far as possible, the tumor should be excised completely along with the envelope, as residual or ruptured envelope may lead to tumor recurrence. Adenoid cystic carcinoma of the lacrimal gland is the most common malignant tumor of the lacrimal gland. Clinical manifestations]: It occurs in 30~40 years old, more common in women, with short course, obvious pain and headache, periorbital and bulbar conjunctival edema, protrusion of the eyeball to the front and bottom, movement disorders, often diplopia and visual impairment. x-ray or CT scan may show bone destruction. The prognosis of this disease is poor. Treatment】Because the disease is highly malignant, it is easy to infiltrate and grow and metastasize to surrounding tissues and bone. Once diagnosed, enucleation of the orbital contents should be considered. Surgery is not easy to remove completely, and the recurrence rate is high. Third, hypersecretion of tears Hypersecretion of tears (lacrima hyposecretion) can lead to dry keratitis and dry eye, which affects vision and is more difficult to cure. Due to the lack of tears, the lack of lysozyme makes the eye lose a protective barrier. Etiology and clinical manifestations] There are many causes of hypersecretion of tears, which can be divided into congenital and acquired, the latter being more common in Sjogren’s syndrome Congenital: congenital lack of tears such as alacrima is seen in Riley-Day syndrome (familial, autonomic abnormalities), which manifests as an absence of tears, corneal perceptual deficits and neuroparalytic keratitis. Although patients may initially be asymptomatic, they will eventually develop the classic dry keratoconjunctivitis. Syndrome: Sjogren’s syndrome, also known as dry keratoconjunctivitis sicca, is an autoimmune disease with multisystem involvement of unknown origin. Primary Sjogren’s syndrome is most commonly seen in women. Secondary Sjogren’s syndrome includes other autoimmune diseases, such as rheumatoid arthritis, systemic lupus erythematosus, scleroderma, and polymyositis. Patients mainly present with ocular dryness and foreign body sensation, and oral dryness. Fluorescein staining reveals diffuse punctate defects on the corneal epithelial surface. In severe cases of corneoconjunctival dryness, lid adhesions and neovascularization may occur, affecting visual acuity. In secondary cases, corresponding other systemic abnormalities may also be present. Non-Sjogren’s hypersecretion of tears is mainly seen in lacrimal gland diseases (e.g., lacrimal gland inflammation, Mikulicz syndrome), post-surgical lacrimal gland, lacrimal duct obstruction due to trauma and infection (e.g., severe trachoma, burns) and reflex tear secretion reduction (e.g., facial paralysis). 【Treatment】 Mainly symptomatic treatment to reduce eye dryness, mainly local treatment, such as methylcellulose. Tearlessness can be treated with tear dots closure to reduce tear loss. Drops of artificial tears can also improve the symptoms. Primary tear hypersecretion (lacrimal hypersecretion) is rare and should be distinguished from tear duct obstruction. Secondary hypersecretion has many causes, such as physical, chemical or emotional stimulation, pharmacological (e.g., pilocarpine) and symptomatic. The latter is seen in certain systemic diseases such as spinal consumption and Parkinson’s disease. A specific type of paradoxical tear secretion is tearing whenever eating, commonly known as “crocodile tears”, which is mainly seen after facial nerve palsy, when the nerve has regenerated in a misaligned manner. The main treatment is to treat the cause. If all methods are ineffective and tearing seriously affects life, destruction of the lacrimal gland or blocking the lacrimal secretory nerve in the pterygopalatine ganglion can be considered to reduce tear secretion.