nasolacrimal duct

anatomy

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Last updated

July 1, 2026

Quick Summary

The nasolacrimal duct is a crucial part of the lacrimal apparatus, which produces and distributes tears. Tears are essential for keeping the eye surface moist, providing nutrients, and offering antibacterial protection.1

Tears are secreted by lacrimal glands and drain from the eye through small openings called puncta, located at the nasal end of the eyelid margins. These openings lead to canalicular ducts, which then connect to the lacrimal sac near the inner corner of the eye. The lacrimal sac empties into the nasolacrimal duct, a tube that directs tears into the nasal cavity.1

Blockages in the nasolacrimal duct can prevent tears from draining, leading to a watery eye and potential inflammation. While often treated in infants with massage, persistent blockages may require surgical intervention.2

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eye disease
Inflammatory conditions of the orbit
…to the nose by the nasolacrimal duct, and infection may ascend this passage from the nose and cause an acute painful swelling at the inner corner of the eye (called dacryocystitis). Blockage of the nasolacrimal duct prevents the passage of tears into the nose and results in a watery eye.…
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…to the nose by the nasolacrimal duct, and infection may ascend this passage from the nose and cause an acute painful swelling at the inner corner of the eye (called dacryocystitis). Blockage of the nasolacrimal duct prevents the passage of tears into the nose and results in a watery eye.…
Read More