What is Nasolacrimal Duct Obstruction?
Congenital nasolacrimal duct obstruction (NLDO), or blocked tear duct, is a relatively common condition in infants (up to 5%) and can result in excessive tear drainage and chronic discharge from the eyes. It is important for your pediatrician or pediatric ophthalmologist to determine that there is not a more serious infection present, such as some types of neonatal conjunctivitis or dacryocystitis (tear sac infection).
What causes a NLDO?
The nasolacrimal duct (tear duct) normally drains tears away from the eye from the tear sac down through the nasal bones and into the nose. Some children are born with a membrane still covering the opening at the nose end of the tear duct that should have opened up at about the time of birth. Because of this tears can not drain away from the eye normally. Bacteria can then multiply in the stagnant tears in the tear duct resulting in discharge that comes back out onto the surface of the eye. Antibiotic eye drops or ointments may help the symptoms temporarily by killing the bacteria but do not solve the underlying plumbing problem. Therefore, the symptoms will usually return when the antibiotic eye drops are discontinued.
How is NLDO treated?
Up to 90% of NLDO's will resolve spontaneously on their own during the first year of life. So initial treatment is usually conservative and involves gently wiping away discharge with a warm moist cloth or using antibiotic drops as necessary for significant discharge. Lacrimal sac (tear sac) massage may be tried and involves forcing pressure down the tear duct to help open the obstruction. Gentle but firm pressure must be placed above the inside corner of the eye then moved in a downwards motion below the inside corner of the eye.
If the NLDO symptoms do not improve by 9-12 months of age, then your pediatric ophthalmologist can perform a probing of the nasolacrimal duct to clear the obstruction. This is done with a blunt instrument passed through the tear duct and into the nose. This is an uncomfortable procedure and thus is usually done under a brief anesthesia, but there is typically no pain for the infant afterwards. Depending on how the nasolacrimal duct feels as it is being probed, your pediatric ophthalmologist may decide to place a stent in the tear drainage system to keep it open as it heals. In most cases this is easily removed in the office weeks to months later. Tear duct probing with or without stent placement is usually very successful, but in rare cases more than one probing may be necessary. Probing may occasionally be done at an earlier age when the symptoms are severe or are causing repeat infections or significant eyelid skin irritation.