Anything passes through the nasolacrimal canal
- The nasolacrimal duct opens into the anterior portion of the inferior nasal meatus of the nasal cavity.
- Tears are secreted by the lacrimal glands located just below the superior margin of the orbit in the lateral angle of eye. Tears drain from the lacrimal punctum, which are openings in the upper and lower eyelid margins of the medial angle of eye, and enter the lacrimal canaliculus to the lacrimal sac.The lacrimal sac is connected to the nasolacrimal duct mentioned above.
- Thus, tears normally flow into the nose, but when secretion is increased, they cannot be expelled by the above methods and overflow, wetting the cheeks.