What is the function of the lacrimal gland and the nasolacrimal gland and how does their positioning aid that function?
The lacrimal gland and nasolacrimal duct are located diagonal from each other across the eye. The nasolacrimal duct appears lower than the lacrimal gland, which creates tears. This positioning creates a flow of fluid across the eye.
Where are the nasolacrimal ducts located and what are they responsible for?
The eye’s tear ducts, also called the nasolacrimal ducts, are small tubes that stretch from the outside of the eye into the nose. They are responsible for carrying tears away from the eyes into the nasal cavity, where they naturally are absorbed or eventually swallowed.
What is the function of lacrimal gland?
The lacrimal gland is located within the orbit above the lateral end of the eye. It continually releases fluid which cleanses and protects the eye’s surface as it lubricates and moistens it. These lacrimal secretions are commonly known as tears.
Where is the nasolacrimal canal?
The nasolacrimal duct (also called the tear duct) carries tears from the lacrimal sac of the eye into the nasal cavity. The duct begins in the eye socket between the maxillary and lacrimal bones, from where it passes downwards and backwards.
What is lacrimal fluid and what are its functions?
It secretes lacrimal fluid (tear fluid), a watery fluid isotonic to plasma, onto the surface of the eyeball. This fluid forms the aqueous portion of a multilayered tear film that lubricates, protects and provides nutrients to the conjunctiva and cornea.
What is nasolacrimal duct?
Tears drain into openings (puncta) on the inside corners of your upper and lower eyelids. The puncta lead to small canals (canaliculi) that move tears to a sac to a reservoir on the side of the nose (lacrimal sac). From there tears travel down a duct (the nasolacrimal duct) and drain into your nose.
What produces lacrimal fluid?
The lacrimal gland (tear gland) is an exocrine gland located above the eyeball, in the anterior part of the upper outer aspect of each orbit. It secretes lacrimal fluid (tear fluid), a watery fluid isotonic to plasma, onto the surface of the eyeball.
What is the nasolacrimal canal?
The nasolacrimal canal is the short bony passage along which the nasolacrimal duct courses in the face. Epiphora accounts for 3% of referrals to ophthalmology, and therefore knowledge of the anatomy of the nasolacrimal drainage system is important 2.
What is the function of the nasolacrimal duct?
The nasolacrimal duct functions by draining old tears from the eye into the nose. From there, the tears are reabsorbed, are wiped away with a tissue or drain into the throat to be swallowed. Tears drained through the tear ducts include more than the ones that appear when we cry.
What is the nasolacrimal system?
From both lacrimal puncta the nasolacrimal system continues as two canaliculi that converge beneath the medial canthal ligament at the level of the lacrimal bone and fossa to form a poorly developed nasolacrimal sac.
How does the nasolacrimal sac enter the nasal cavity?
From the ventral portion of the lacrimal sac emerges the nasolacrimal duct to traverse the small intraosseous canal of the maxillary bone to enter the nasal cavity within the maxilloturbinate to the nasal meatus.