Congenital nasolacrimal duct obstruction occurs when the lacrimal duct has failed to open at birth, most often due to an imperforate membrane (Hasner Valve) at the inferior end of nasolacrimal duct. Consequently, tears can not drain into nose as they should, flow out of the eye and run down the cheeks. Either one or both ducts can be affected.
These babies present a persistent watery eye even when not crying. A sticky and mucupurulant discharge may be present if a secondary infection occurs.
Most cases resolve in few months after birth, by opening of the obstructing membrane spontaneously. Lacrimal sac massage (hydrostatic pressure) may help in mechanical opening the duct. The massage is applied on the outside of child’s nose (from the eye to the corner of the nose) with a clean index finger. A relatively firm pressure should be applied during the massage.Topical antibiotic drops can be used at times when secondary infection and purulent discharge occurs. The eye should be cleaned using cooled pre-boiled water or saline.
If it does not resolve spontaneously in the first year of life, mechanical probing (a procedure to open the ducts using a tiny probe) with or without a silicone tube intubation may be done under general anesthesia. Although, early invasive procedures within one year of age without anesthesia have been proposed, they may cause iatrogenic damage to canaliculi and cause permenant cicatricial obstructions.
Nasolacrimal duct probing with or without intubation has a high success rate in opening obstructions and stopping the overflow of tears. In delayed or failed cases following repeated attempts after early childhood, other surgical options same as in adults may have to be considered. A dacyrocystorhinostomy operation requiring bone fracture is usually done after 4 to 5 years of age.
Other causes of epiphora (watering) should be kept in mind in newborn babies.
A newborn baby can pick up infection of bacteria (chlamydia or gonorrhea)during vaginal birth from an infected mother. This severe type of conjunctivitis may be prevented with the use of desinfectant or antibiotic eye drops in newborns at birth. The symptoms of newborn conjunctivitis usually start about 2 to 5 days after birth. The condition causes very red eyes with edema and intensive purulent discharge. Treatment often requires systemic antibiotics.
Babies with congenital glaucoma present excessive tearing with photophobia. The elevated intraocular pressure enlarges the eyeball (buphthalmus) which is highly soft and elastic in babies.
At first, the babies with congenital glaucoma, which is a very serious eye disease leading to blindness, may be misestimated as if they have 'beautiful big eyes'. And, on the other hand, excessive tearing may be misdiagnosed as 'lacrimal duct obstruction'.
In babies with congenital glaucoma, the excessive tearing is associated with intense photophobia (intolerance to light) and blepharospasm (i.e. keep eyes shut when exposed to sunlight).They usuaaly keep their eyes in mother's bosom away from light.
The presence of any foreign body on ocular surface can cause the baby’s eyes to become watery as well.
The inward turning of eyelid margins and eyelashes (mostly epiblepharon or rarely congenital entropion) do rarely cause irritation and tearing in babies as the eyelashes are yet very soft and tiny.