Lacrimal sac

(Redirected from Tear sac)

Definition

noun, plural: lacrimal sacs

The upper portion of the nasolacrimal duct from where the two lacrimal canaliculi empty


Supplement

In humans, the lacrimal sac is that part found in the upper portion of the nasolacrimal duct. It is approximately 12 mm in length. It is part of the lacrimal apparatus, which is a system involves in tear production and tear drainage. Apart from the lacrimal sac, the lacrimal apparatus is comprised of the lacrimal glands, lacrimal canaliculi, and nasolacrimal duct. The lacrimal glands are essential in the production of lacrimal fluid. The lacrimal canaliculi and nasolacrimal duct are parts of the tear drainage system of the lacrimal apparatus. The lacrimal canaliculi are from where the tears drain from the surface of the eye whereas the nasolacrimal duct is a passageway of the fluid into the nasal cavity.

The lacrimal sac is the dilated part of the nasolacrimal duct. Its upper end though is closed. Its function is to act as a reservoir of tears when there is an excess production resulting in the overflow of tears.


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