Tears keep the front surface of the eye moist
and help to wash it during each blink. Without tear film eye gets dry “Dry eye syndrome”. Tear glands form the tear. By blinking the tear covers the eye
and lower lid moves the tears sideways towards nose, moving the “old” tear and accumulated dust debris to the nasal corner of eye to be drained out.
Excessive tearing in adults may be because of over production or poor drainage through nasolacrimal duct
(canal) in nose.
Drainage system of eye:
It starts at a bump called lacrimal papillae situated on the nasal side of eyelid margin. At the top of bump is a small hole called punctum. This leads to a tubular passage ( the canaliculus) that connects to a small bag called lacrimal sac. The sac is connected to nose by nasolacrimal duct
(canal) where the tear is drained.
Excess tear is produced by:
Wind and smoke.
Infections and allergic reaction.
Poor drainage is by:
Malpositioned eyelid or punctum.
Faulty blinking as after facial nerve palsy.
Infection of lacrimal sac.
After burns and radiation therapy.
Sometimes the cause cannot be determined and the patient may have to live with the problem.
Treatment depends on the cause. Foreign body and misdirected eyelashes need removal. Abnormality of lids needs surgery to correct it. While blockage of tear drainage channel may need surgery to create additional passage from lacrimal sac into the nose, a procedure known as dacryocystorhinostomy or DCR.