LACRIMAL GLAND PART 2

Question 1

what does the schirmer’s tear test test for? when do you do this test? (quantitative test)

Answer 1

quantity of tears produced. you do this test when patient has dry eye or excessive watery eye.

Question 2

describe the schirmer’s test.

Answer 2

give anesthesia, wait a minute, put tear film on temporal side of eye, record result after 5 minutes. Measure wet part of strip: 15mm or more is normal. for patients 60 yrs or older 10mm may be normal.

Question 3

What does a qualitative tear film test for? name the two types of tests.

Answer 3

tear film stability.
TBUT (tear break up time)= invasive (10 seconds or less)
Results:
normal (clear, clear, clear)
not normal (clear, blurry after blink, clear)
Keretometer mire= noninvasive (10 sec or less)

Question 4

what affects the outcome of schirmer’s test? how can you get a false negative?

Answer 4

if you place strip on nasal side instead of temporal side can get false negative result.
Also, reflex tearing, effects of anesthesia, age variation, and subjective measurement.

Question 5

How much tears define normal, mild, moderate or severe dry eye in schirmer’s test?

Answer 5

After 5 min:
normal tears= 15mm or more
mild dry eye= 14mm-9mm
moderate dry eye= 8-5mm
severe dry eye= 4mm or less

Question 6

what does an ocular surface assessment do?

Answer 6

test surface of integrity by using tissue sampling cytology and staining techniques in eye.

Question 7

What is the function of acinar cells do in lacrimal gland?

Answer 7

secrete fluid composed with electrolytes, similar to the plasma

Question 8

what does the Na+ K+ ATPase pump do?

Answer 8

sends Na+ and water out and lets K+ in.

Question 9

what is the difference between hypertonic and isotonic?

Answer 9

hypertonic= low pressure
isotonic= high pressure

Question 10

what do ductal cells do in lacrimal glands?

Answer 10

ductal cells modify acinar cell fluid by secreting fluid rich in KCl.

Question 11

what is the difference between lacrimal fluid and plasma?

Answer 11

higher K+ and Cl- concentration.

Question 12

The secretory cells of the lacrimal gland are innervated by what?

Answer 12

nerves innervated by secretory cells and steroids and peptides found in the blood that stimulate secretion

Question 13

the lacrimal gland is innervated by what?

Answer 13

parasympathetic, sympathetic, and sensory nerves.

Question 14

which one is the main contributor of tear production in lacrimal gland….Sympathetic or Parasympathetic nerves?

Answer 14

Parasympathetic fibers of CN VII is the main contributor of tear film and secretion.
Stimulation of sympathetic nerves produces no change in tear film.

Question 15

stimulation of the lacrimal secretory cells can be caused by?

Answer 15

norepinephrine, bright light hitting optic nerve, sensory nerve at optic surface, acetylcholine and VIP (Vasoactive Intestinal Protein)

Question 16

what is the function of the conjunctiva?

Answer 16

Provides passage for the secretion produced by the lacrimal gland and accessory lacrimal glands
Sero-mucous secreting tissue

Question 17

conjunctiva reactions can be provoked by what?

Answer 17

allergy, infection or inflammation

Question 18

reactions to conjunctiva are characterized by what two structural changes?

Answer 18

papillae formation and follicle formation

Question 19

papillae has macrophages and lymphoctyes…..true or false.

Answer 19

false….follicles are made of macrophages and lymphoctyes.

Question 20

follicles have blood vessels above and below but never inside. true or false

Answer 20

true. follicles are viral.

Question 21

where is papillae commonly found on upper or lower lid? what are they composed of?

Answer 21

upper eyelid. they are composed of neutrophils an eosinophils.

Question 22

papillae have blood vessels in the center. True or False.

Answer 22

true. usually found in contact lens wearers.

Question 23

Are eosinophils and basophils present in normal conjunctiva epithelium? If not, what conditions are they present in?

Answer 23

No. they are present in two conditions. Vernal conjunctivitis
Giant papillary conjunctivitis

Question 24

If a contact lens has dislocated and cannot be seen in the eye, where should you check first?

Answer 24

superior fornix. has the greatest depth. not possible for contact to go to back of eye.

Question 25

Name the layers of conjunctiva.

Answer 25

epithelium and stroma

Question 26

how many layers does the conjunctiva epithelium have? Where does it become continuous with the cornea?

Answer 26

there are 2-4 layers.

it becomes continuous with the cornea at the limbus, where it thickens.

Question 27

what is located immediately peripheral of the limbus?

Answer 27

palisades of Vogt folds (increase of epithelium 4-5 times more). Have increased wing cells.

Question 28

what do limbal stem cells reserve do?

Answer 28

contribute cells continually to cornea and also serve as reserve in event of trauma.

Question 29

what are goblet cells and where are they located?

Answer 29

Goblet cells are unicellular mucin secreting glands. Are sparse in number in bulbar conjunctiva. More frequent in palpebral conjunctiva and fornix. They are located in the bulbar conjunctiva, palpebral conjunctiva and fornix.

Question 30

what is the function of the stroma in the epithelium of the conjunctiva?

Answer 30

rich network of capillaries. supply nutrients and blood needed to create new goblet cells and regeneration of epithelium. consists of adenoid layer and deep fibrous layer.

Question 31

what are mast cells? where are they found usually?

Answer 31

Mast cells (similar to basophils) come from injury. responsible for immediate hypersensitivity reaction (allergies). Contain chemical mediators for inflammation, such as histamine and heparin. 
Found in stroma of the conjunctiva where eosinophils and basophils are. NEVER FOUND IN EPITHELIUM.

Question 32

What happens to make physical properties of mast cells change? What binds to the mast cell?

Answer 32

IgE binds to mast cell causing physical change to membrane and cytoplasm of cell, making it more permeable to Ca+ and let more Ca+ in. This lets more water in and can cause edema.

Question 33

In infections of conjunctiva, what nerves are engorged? In keratitis or iritis what nerves are engorged?

Answer 33

keratitis (inflammation of cornea) or iritis (inflammation of iris) = deep ciliary vessels engorged

conjunctiva infection= superficial posterior vessels engorged

Question 34

Are the lyphatics of the eye located in the conjunctiva, the globe, or both? In what direction does the lymph flow?

Answer 34

Located in the conjunctiva only. NO LYMPHATICS FOUND IN GLOBE.
I flows temporally toward the lateral extremities of the lid to eventually connecting with carotid node.
Medial route leading to submandibular lymph glands.