Lacrimal System and Conjunctiva Flashcards Preview

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Flashcards in Lacrimal System and Conjunctiva Deck (77)
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1

what is the main provider of the aqueous secretory component of the tear film

the main lacrimal gland

2

where is the main lacrimal gland located

in the fossa for the lacrimal gland (anterio-lateral orbit)

3

what divides the lacrimal gland into orbital and palpebral lobes

the lateral horn of the levator and extensions of Mullers muscle

4

which lobe of the lacrimal gland, orbital or palpebral, is larger

the orbital, it lies behind the orbital septum and above the levator aponeurosis

5

what is the normal color of the lacrimal gland

pinkish-gray

6

what is the lacrimal gland made up of (drains)

many acini that drain into larger tubles

7

what type of tissue are acini made of

basal myoepithelial cell layer with inner columnar secretory cells

8

why is it important that acini are myoepithelial cells

it requires muscle movement to allow the contents to be drained

9

when does the lacrimal gland begin to develop

near the third month of fetal life

10

when does the lacrimal gland begin functioning after birth

it may be as long as 2 months

11

when do newborn babies start to produce tears

2 weeks after birth

12

if the lacrimal gland doesn't produce tears in infants, what keeps their eyes from drying out

their accessory glands are functional

13

what are the secondary providers of the aqueous secretory component of the tear film

glands of krause and wolfring

14

what was the historical perspective of the accessory glands

that they were for the main secretion (basal tearing) and the lacrimal gland was for reflex tearing

15

where are the glands of wolfing located

in the tarsal plate of the eyelid

16

which lid, upper or lower, has more accessory glands

the upper lid

17

what are trilaminar tears

3 layers: aqueous, mucus, and lipid

18

where are the glands of krause located

in the conjunctival fornix

19

what are the 3 arterial supply sources to the lacrimal gland

the lacrimal branch of ophthalmic artery, branch of the infraorbital artery and the recurrent meningeal artery

20

what is the sensory innervation to the lacrimal gland

the lacrimal branch of the trigeminal nerve (5)

21

what other ocular structure has innervation from the trigeminal nerve

the cornea

22

what is the order of the 3 layer structure of the tear film

outer lipid layer, middle aqueous layer, inner mucous layer

23

what is the primary source of oxygen to cornea

the tear film (the cornea is avascular)

24

besides supplying oxygen to the cornea, what are the other functions of the tear film

lubricant between lids and ocular surface, remove foreign bodies, debris, and has antibacterial proteins for protection

25

where does the lipid layer of the tear film come from

meibomian glands and gland of zeiss

26

where does the aqueous layer of the tear film come from

lacrimal gland, fornix accessory lacrimal gland (krause) and palpebral accessory lacrimal gland (wolfring)

27

where does the mucus layer of the tear film come from

goblet cells, epithelial cells, and lacrimal gland (very little)

28

how thick are each of the 3 layers of the tear film

lipid is 0.1 microns, aqueous is 7 microns, and mucus is 0.02-0.05 microns

29

what type of glands are the meibomian glands

sebaceous glands that secrete lipids onto the tear film

30

what is holocrine secretion (meibomian glands)

when the discharged secretion contains the entire secreting cells laden with the secretory material