5 - Lacrimal System Evaluation (Exam 1)

Question 1

What does the lacrimal system do?

Answer 1

Produce, distribute, and drain the tear film

Question 2

What is responsible for reflex secretion?

Answer 2

The lacrimal gland

Question 3

What is the innermost layer of the tear film and what is it produced by?

Answer 3

Mucin layer

Conjunctival goblet cells, tarsal crypts of Henle

Question 4

What is the middle layer of the tear film and what is it produced by?

Answer 4

Aqueous layer

Glands of Krause and Wolfring, lacrimal gland

Question 5

What is the outermost layer of the tear film and what is it produced by?

Answer 5

Lipid layer

Meibomian glands, Glands of Zeis

Question 6

Which layer of the tear film makes up the majority?

Answer 6

Aqueous (middle) layer

Question 7

What 3 things would an aqueous layer deficiency result in?

Answer 7

1. Dry, burning eyes
2. Intolerance of dry air
3. Mucous strands present in the eye

Question 8

What would a mucin layer deficiency result in?

Answer 8

Dry, burning eyes

Question 9

What would a lipid layer deficiency result in?

Answer 9

Dry, burning eyes

True lipid deficiency is very rare

Question 10

What is often a cause of mild lipid deficiency?

Answer 10

Chronic blepharitis or meibomianitis

Question 11

What are the 2 types of lid apposition?

Answer 11

Ectropion

Entropion

Question 12

How does ectropion impact the distribution of tears?

Answer 12

Tears do not properly drain because inferior punctum does not contact tear lake

Question 13

What is epiphora?

Answer 13

Excessive tears running down the cheeks

Often a result of ectropion or entropion

Question 14

How does entropion impact the distribution of tears?

Answer 14

Lashes turn inward and result in reflex tearing

Overabundance of aqueous layer results in change in osmolarity and epiphora

Question 15

What are 3 types of exposure disorders related to dry eye?

Answer 15

1. Partial blinker
2. Nocturnal lagophthalmos
3. Exophthalmos

Question 16

How are tear production disorders commonly treated?

Answer 16

Artificial tears
Punctal plugs
Restasis

Question 17

How are tear distribution disorders commonly treated?

Answer 17

Surgical repair if lid apposition present
Lubricating ointments/taping lids shut during sleep
Treatment of underlying disease (hyperthyroid)

Question 18

How are tear drainage disorders commonly treated?

Answer 18

Medical or surgical treatment

Question 19

What are 3 types of tear drainage disorders?

Answer 19

1. Epiphora (congenital or acquired)
2. Canaliculitis
3. Dacryocytitis

Question 20

What is dacryocystitis?

Answer 20

Infection/ inflammation of the lacrimal sac

Question 21

What are 5 important clinical evaluation procedures involving the lacrimal system?

Answer 21

1. Observe lid position and puncta position
2. Tear meniscus evaluation
3. Vital dyes (fluorescein, rose bengal, etc.)
4. Tear break up time
5. Examine lids/lashes

Question 22

What are 3 additional procedures used to supplement lacrimal system findings?

Answer 22

1. Schirmer tests
2. Jones dye tests
3. TearLab

Question 23

What is a normal tear break-up time?

Answer 23

10-15 seconds

Question 24

What would a dry eye patient’s Schirmer test results show?

Answer 24

Less than 5 mm of tears after 5 minutes

Question 25

What is the normal expectation for Schirmer test results?

Answer 25

> 10 mm of tears in 5 minutes

Question 26

What do normal Meibomian gland expressions resemble?

Answer 26

Baby oil