What is Nasal Lacrimal Duct Obstruction?
Tears normally drain through small openings in the corners of the upper and lower eyelids called puncta and enter the nose through the Nasal Lacrimal Duct. Nasal Lacrimal Duct Obstruction prevents tears from draining through this system normally. What causes Nasal Lacrimal Duct Obstruction in children? The most common cause is the failure of a membrane at the end of the Nasal Lacrimal Duct (valve of Hasner) to open normally at or near the time of birth. Other causes of blocked Nasal Lacrimal Ducts in children include: • Absent punctum (upper and/or lower eyelid) • Narrow or stenotic system • Infection • Nasal bone that obstructs the Nasal Lacrimal Duct entering the nose. How common is Nasal Lacrimal Duct Obstruction? Over 5% of infants have symptoms of Nasal Lacrimal Duct Obstruction affecting one or both eyes. Over 90% clear spontaneously during the first year of life. What are the signs/symptoms of Nasal Lacrimal Duct Obstruction? Blockage of the drainage system causes tears to well
