Lacrimal disorders and dry eye evaluation

Question 1

what is ephiphora

Answer 1

normal amount of tear production w/ impaired tear drainage

Question 2

what is lacrimation

Answer 2

over secretion or production of tears

Question 3

what does the jones test measure

Answer 3

tests patency/blockages btwn the puncta and inf meatus of the nose

• check puncta all the way to nasolacrimal duct if open, doesnt tell you location but identify presence of blockage
• fl in eye and have pt blow nose in tissue and look for staining

Question 4

what does the regurgitation test check

Answer 4

patency btwn puncta and lacrimal sac

-fl in eye, pull lower lid, locate puncta and press on nasolacrimal sac

Question 5

what is dacryocystitis

Answer 5

infection of the lacrimal sac and/or obstruction of the naso-lacrimal duct

Question 6

what can dacryocystitis lead to

Answer 6

pre-septal cellulitis

Question 7

what glands are involvd in the lipid layer

Answer 7

meibomian glands

gland of zeiss

Question 8

what is the purpose of the lipid layer

what is it composed of

Answer 8

• stabilizes tear film
• reduces evaporation of aqueous component
• outer layer
• composisition of cholest, fatty acids, phospholipds
• lowers surface tension of tear film=> draw water into and thickens aqueous

Question 9

deficiency of the lipid layer is from

Answer 9

lid problems
contact lenses
-bells palsy
-MGD

Question 10

what is the aqueous layer produced by

Answer 10

lacrimal gland and accessory lacrimal gland of kraus and wolfring

Question 11

what is the thickest layer of tear film

Answer 11

aqueous 7-8 microns in thickness

Question 12

what is the composition of the aqueous layer

Answer 12

salts 
proteins
glucose
lactate
water soluble molec

Question 13

what is a deficiency of the aqueous layer from

Answer 13

decrease in lacrimal gland tear production

trauma

Question 14

what is the aqueous responsible for

Answer 14

basic aqueous secretion, major portion of tear film

• carrying nutrients and oxygen towards cornea
• lysozymes prevent infections from reaching cornea

Question 15

what is the mucin layer produced by

Answer 15

goblet cells with crypts of henle, gland of manz

Question 16

what is a deficiency of the mucin layer caused by

Answer 16

vitamin A
trachoma
lasik surgery

Question 17

what does the mucin layer do

Answer 17

converts corneal ep from hydrophobic to hydrophilic

Question 18

what is the contempory model of tear film

Answer 18

one continuous layer

varying amounts of mucin throughout tear film w/ higher conc on bottom (mucin layer)

Question 19

why is elevated tear osmolarity a characteristic of dry eye

Answer 19

goblet cell number is decreased, which decresaes mucin, which decreases aqueous, lipid, lysozymes which all affect osmolarity

Question 20

what is the role of gycocalyx

Answer 20

helps bring mucin to the corneal surface

Question 21

what mucin help to create gycocalyx

Answer 21

mucin 1, 4, 16

Question 22

what are the risk factors to dry eye

Answer 22

1. age: atrophy of meidb glands, decrease in hormone production: androgens
2. hormonal regulatios: adrogens in lacrimal gland/meib glands and an immuno-suppreive effect (women)
3. environmental factors: air dryness, near task, altitude, smoking
4. systemic disease: sjogren’s syndrome (triad symptoms, severe dry eye, mouth, rheumatoid arthritis)

Question 23

what is the neurotrophic theory

Answer 23

severing of nerves in corneal stroma, takes 3 months to regnerate and may contribute to lack of sensory input back to lacimal and accessory lacrimal glands

Question 24

what are the theories of lasik contributing to dry eye

Answer 24

1. neurotrophic theory: severing nerves in corneal stroma lacrimal and accessory lacrimal glands affected
2. suction ring during lasik: disrupts goblet cells at limbus, decrease mucin production

Question 25

what are the underlying causes of dry eye

Answer 25

evaporative: alters ocular surface=> low grade infl inflammatory: low grade infl in tears and ocular surface, infl cytokines and T cells in lac glands and conj

Question 26

patients with what diseases are twice as likely to have dry eye

Answer 26

blepharitis | meibomianitis

Question 27

classfying bleph as ant are what diseases? post?

Answer 27

ant: staph bleph seborrheic blph post: meibomian dys

Question 28

what is the relationship btwn dry eyes and: allergies, bleph, eye drops/dry eye disease, conjunctivitis

Answer 28

1. allergies: loss of goblet cells 2. bleph: impairment of lipid laer=> inc rate of tear evap 3. eye drops and eye dieases: preservatives are cytotoxic 4. viral conjunctivitis: loss of goblet cells, release of cytokines

Question 29

what are the inflammatory mediators in dry eye

Answer 29

cytokines and leukotrines

Question 30

in lid evaluation for dry eye, what are you looking for

Answer 30

1. examin lid margin (bleph, mgd_ 2. inf corneal staining, blinking patterns 3. evaluate blink rate and tear flow (dec w/ prolonged near work, incomplete blinking) 4. examine lacrimal drainage (steonsis of puncta, blockage of nasolacrimal duct) 5. lid apposition abnormalities (ectropian)

Question 31

what is lagophthalmos

Answer 31

inability of lid closure

Question 32

what is the normal tear meniscus height

Answer 32

0.2-0.5mm in height and smooth

Question 33

what does schirmer's test test for

Answer 33

tear volume of reflex and baseline tears | >10mm in 5 min is normal

Question 34

what does schirmer's 2 test test for

Answer 34

use anesthetic so only test baseline tears | 5mm in 5 min

Question 35

what is the norm for phenol red test

Answer 35

>13mm + or - 4mm 15 sec OR >10mm in 15 sec

Question 36

what is the norm for TBUT

Answer 36

20-30 sec 15-20 young 10 in aging cl wearers less TBUT, keep environment in mind

Question 37

what kind of staining will a superficial punctate keratitis give

Answer 37

isolated loss of ep cells, small diffuse

Question 38

what kind of staining will a moderate to severe dry eye give

Answer 38

coalesced areas of ep cell loss, punctate erosions when lose large areas of ep cells

Question 39

what will give a geographic area of fl staining

Answer 39

large area of cell loss, very severe dry eye

Question 40

what does rose bengal and lissamine green stain? | which works better

Answer 40

stains dead ep cells and mucin rose bengal picks up on dead cells on cornea better -lissamine green is less toxic to cells , less cytotoxic

Question 41

how does filamentary keratitis show up

Answer 41

"filaments" | dead cells wrapped w/ mucin, on advanced dry eye