
Congenital nasolacrimal duct obstruction (CNDO) is the most common lacrimal system disorder encountered in pediatric ophthalmology, occurring in approximately 5% of infants. It is usually congenital in origin resulting from a failure of canalization of the nasolacrimal duct. The obstruction is most commonly at the valve of Hasner where the nasolacrimal duct would normally enter the nose. It is the most common cause of epiphora in infants, however more specific signs include the presence of high tear meniscus and mucoid discharge that may cause crusting of the eyelid margins and skin erythema. CNDO resolves spontaneously in most cases, but a subset of patients have persistent symptoms that require treatment. Conservative management with lacrimal sac massage is the first line of management within the first year of life. After said time patients unresponsive to conservative management often undergo an intervention to surgically open the obstruction, including probing, balloon dacryocystoplasty, silicone intubation, inferior turbinate fracture, endoscopic intranasal surgery and dacryocystorhinostomy (DCR).However, no consensus has been reached regarding either optimal timing or type of intervention, so the decisionshould be based between patients family and the ophthalmologist.