If a large amount of tears is a pathological manifestation, the main reasons are as follows: 1. Excessive tear secretion caused by tissue lesions of the conjunctiva, cornea, iris, ciliary body, or stimulation by foreign bodies, ultraviolet light and chemicals. For example: conjunctivitis, keratitis or corneal ulcer; corneal epithelial abrasion, corneal epithelial peeling, corneal foreign body, conjunctival sac foreign body; this condition requires foreign body removal and anti-inflammatory treatment. 2, due to the lacrimal system obstruction, the normal secretion of tears can not be smoothly discharged into the nasal cavity through the nasolacrimal duct, but reflux overflow. For example: tear dots obstruction, tear duct obstruction, nasolacrimal duct obstruction, chronic dacryocystitis, etc. In this case, it is necessary to do lacrimal tract exploration. 3. Due to eyelid deformity and lower lid ectropion, the tear dots located on the lower lid are not close to the eyeball and tears cannot enter the tear dots and tears cannot enter the nasal cavity by the tear ducts, thus overflowing. This condition requires plastic surgery to lift the deformity. 4, eyelid closure difficulties, such as facial nerve palsy resulting in relaxation of the orbicularis oculi muscle, resulting in insufficient suction of the lacrimal sac, can also lead to tears can not enter the tear duct normally, and thus overflow. This condition requires treatment of facial nerve palsy. Therefore, different treatments need to be done depending on the cause.