Eyes usually have just enough tear fluid to keep them wet. Some young children are born with a constant overflow of tears. Tears normally leave the eye through tiny openings on the edges of the eyelids. After passing through these openings, the fluid drains into the nose through little “tubes” called nasolacrimal ducts. It is not unusual for a baby to be born before these ducts are completely open. This usually has no effect except for watery eyes. Most children just grow out of it– there is a high spontaneous rate of remission (60-90%) in the first year of life. The condition can become more serious, however, when tear fluid builds up inside the nasolacrimal duct. Eventually, the duct can become irritated and infected. This can lead to a permanent blockage called nasolacrimal duct obstruction.
Placing a warm, wet, clean washcloth on the child’s eye a few times a day can help the fluid inside the duct drain out. It is also sometimes helpful to massage gently between the child’s eye and nose with a clean finger. Usually, antibiotic drops are not necessary as the infection is in the tear film (I.e. not a true conjunctivitis) and is due to commensals; germs that live in the upper end of the nose all of the time. This low-grade infection rarely progresses to true conjunctivitis and the child’s eyes are hardly ever red. Cleaning away the mucopus (yellowish fluid) with cotton wool soaked in cooled boiled water is usually all that is necessary. Start at the nasal side and wipe away towards the ear. Once everything is dry, apply Vaseline to the skin of the lower lid to protect it from the excess watering. Massaging the sac using the Crigglar technique has been shown to help and is demonstrated in a neat little video HERE.
It can take up to 14 months for the nasolacrimal duct to open on its own. Probing should be delayed until 10-12 months of age. Parents can be instructed to undertake lacrimal sac massage during the intervening period. Earlier probing is only justified if there is severe recurrent infection or the obstruction is causing other problems, the doctor might recommend a procedure to open the duct. This is called nasolacrimal duct probing. The doctor will probably prescribe antibiotics before the probing if there is an infection.
Under general anaesthetic, a thin metal probe that is passed through the opening in the eyelid. This wire probe then passes through the nasolacrimal duct down to where it opens inside the nose several times.. Clean water is squirted through the nasolacrimal duct to make sure it can get through. Nasolacrimal duct probing is very successful in opening obstructions and stopping the overflow of tears in upwards of 80% of cases.
Sometimes the obstruction cannot be cleared by probing. Ophthalmologists can perform a procedure that is something like nasolacrimal duct probing, but instead of using a wire probe that is taken out at the end of the procedure, a small plastic tube in placed which stays inside the duct for several weeks or months. This tube forces the nasolacrimal duct to stay open, and the duct usually remains open even after the device is removed.
If this fails then further surgery may be contemplated and this will involve referral to a specialist centre.