[Nasolacrimal duct disorders in children. Part I. Anatomy, physiology and clinical signs].

Congenital nasolacrimal duct obstruction (CLDO) is considered as common and onerous disorder present at infancy. Over 5% of infants have CLDO affecting one or both eyes. The symptoms of CLDO appear shortly after birth or during the first weeks of life. The main symptoms are: excessive and persistent watering, ropy mucous discharge in the conjunctival sac. In conservative treatment a lacrimal sac massage is proposed, though it is not always successful. Topical antibiotics are reserved only if secondary conjunctivitis occurs. Fortunately, most cases resolve spontaneously. However, sometimes nasolacrimal duct probing performed under local or general anesthesia is necessary.