7 - Nasolacrimal System

Question 1

4 functions of tear film

Answer 1

Optic, comfort, metabolism, immune system

Question 2

How does the tear film provide comfort

Answer 2

Keeps the surgace of cornea and conjuctivial moist to allow tissue to slide across one another

Question 3

How does tear film provide metabolism

Answer 3

Transfers oxygen from air to cornea, provides and transports nutrients, electrolytes, growth factors, removes debris

Question 4

How does tear film help with immune system

Answer 4

Prevent infection due to present of anti bacterial substances - IgA, lysozyme, lactoferrin

Question 5

How long foes it take for teaser fil to break up when blinking is prevented

Answer 5

20 - 40 seconds

Question 6

Up to what % of tear volume evaporates normally

Answer 6

25

Question 7

How long does it take for the aqueous tears to evaporate completely - turn over time

Answer 7

10 mins

Question 8

Inner later of tear film

Answer 8

Aqueous mucous layer

Question 9

Outer later of bi layered tear film

Answer 9

Lipid layer

Question 10

What glands produce aqueous

Answer 10

Orbital/ lacrimal and nictans/third eyelid

Question 11

Orbital/ lacrimal gland are along

Answer 11

Internal surgace of zygomatic proces of frontal bone and orbital ligament

Question 12

Nictan / third eyelids are located

Answer 12

Deep in the medial orbit

Question 13

Lipid component are secreted by

Answer 13

Meibomian/tarsal glands

Question 14

What are resonpsile for productions mucin

Answer 14

Conjuctivial goblet cells

Question 15

75% of tears drain down

Answer 15

Nasolactimal duct

Question 16

Afferent nerves arise in

Answer 16

Cornea and conjunctiva

Question 17

Opthalmic division of trigeminal nerve communicates to

Answer 17

Lacrimal nuclues of facial nerve in ponds

Question 18

efferent nerves

Answer 18

Supply the glands

Question 19

Schirmer tear test

Answer 19

Quantifies reflex and basal aqueous production

Question 20

Normal dogs schirmer tear test

Answer 20

15 - 25 mm/min

Question 21

Normal cats schirmer tear test

Answer 21

Great than 8 mm/min

Question 22

Normal horse schirmer tear test

Answer 22

Great than 11 mm

Question 23

Test can you do on excites with small eyes

Answer 23

Phenol red thread test and ended on tic paper point test

Question 24

Jones test

Answer 24

Evaluate passage of fluid down the nasolactimal duct

Question 25

Tear film break up test

Answer 25

Fluorescein stain - evaluates tear stability

Question 26

Lissamine green dye stain

Answer 26

Dead epithelial cells

Question 27

Rose bengal dye stains

Answer 27

Where there is absence of mucin

Question 28

Reflex secretion

Answer 28

Secretion secondary to mechanical irritation from hairs or foreign bodies, painful ocular disease or irritants such as light and wind

Question 29

If overproduction causes epiphora what is it called

Answer 29

Reflex secretion

Question 30

Micropunctum TX

Answer 30

Enlarged the opening

Question 31

Imperforate punctum TX

Answer 31

Create an opening

Question 32

Diagnostics for epiphora

Answer 32

Ophthalmic exam, jones test, nasolacrimal duct flushing

Question 33

Dacryocytstits

Answer 33

Primary infection or infection secondary to foreign body in the duct or lacrimal sac or congenital duct atresia

Question 34

TX for dacryocystitis acute

Answer 34

Attempt to flush the duct, topical AB and systemic AB. + NSAIDs for 6 weeks

Question 35

Feline herpes virus can cause

Answer 35

Cicatrical nasolacrimal obstruction

Question 36

Tear staining

Answer 36

Staining of the hair at the medical canthus due to porphyrins + light coat