Lacrimal canaliculi

For nasolacrimal duct obstruction. Catheterization of intranasal lacrimal canaliculi: 1. The eyelid must be fixed when probing, so that the lacrimal canaliculus is always tightened and straightened, so as not to damage the lacrimal canaliculus and normal tissues around it, causing false ducts. 2. When probing the nasolacrimal duct, the probe should use the nasal bone wall of the dacryocyst as the fulcrum, and rotate the tail of the needle by 90 °. Advance, the same operation when intubation, so as not to damage normal lacrimal duct tissue. 3. The plastic pipe ring located between the upper and lower punctum of the inner crotch must be placed tightly and moderately. If it is too loose, the plastic tube will rub the eyeball when the eyeball moves, causing a foreign body sensation; if it is too tight, it will easily break off the tear duct. The lower plastic tube should also be properly hidden in the nasal vestibule to prevent tears and tear ducts from being accidentally pulled.