3. Anatomy of lacrimal System. Clinical evaluation.

Question 1

where is the lacrimal gland located ?

Answer 1

in the upper outer corner of each eye , in the lacrimal fossa between anterior & posterior lacrimal crests

Question 2

where is the puncta located ?

Answer 2

medial end of each eyelid there is the upper hand lower puncta

Question 3

how does the lacrimal system work ?

Answer 3

the serous lacrimal gland secretes the tears , its ducts ending at the surface of the eye

the tears are then bought to the puncta which then drain into the canaliculus then the common canaliculus which ends in the lacrimal sac

from the lacrimal sac it moves into the nasolacrimal duct through the valve of hasner

emptying into the inferior nasal meatus

Question 4

how is the lacrimal gland stimulated ?

Answer 4

from the sympathetic nerve of the carotid plexus around the internal carotid artery

parasympatheticaly from the lacrimal nucleus of the facial nerve

Question 5

describe the mechanism of how th tears move ?

Answer 5

With each blink, the superficial and deep heads of the pretarsal orbicularis muscle compress the ampullae, shorten the horizontal canaliculi and move the puncta medially

When the eyes open the muscles relax, the sac collapses and a positive pressure is created which forces the tears down the nasolacrimal duct into the nose