Silicone tube intubation is used in children and adults when the lacrimal ducts are narrowed but not completely closed (relative stenosis). The principle is to splint and dilate the tear ducts. For this purpose, a thin silicone tube is inserted into the tear ducts under general anesthesia and knotted in the nose. The tube is left in place for 3-6 months and can then be removed under local anesthesia.