Eyelid and Third Eyelid

Question 1

Define blepharospasm.

Answer 1

Spasm of the orbicularis oculi muscle resulting in eyelid closure
Squinting

Question 2

Define cilia.

Answer 2

Eyelashes

Question 3

Define distichia.

Answer 3

Eyelashes which emerge from the Meibomian glands

Question 4

Define ectopic cilia.

Answer 4

Eyelashes protruding through the palpebral conjunctiva

Question 5

Define ectropion.

Answer 5

The outward rolling of the eyelids

Question 6

Define eyelid margin.

Answer 6

Identified by the grey line of Meibomian gland orifices
Important landmark to identify when closing the eyelid surgically

Question 7

Define entropion.

Answer 7

Rolling of the eyelid margin such that hairs are touching the ocular surface

Question 8

Define lagophthalmos.

Answer 8

Incomplete eyelid closure/coverage of the eyeball

Question 9

Define ptosis.

Answer 9

Drooping of the eyelids caused by sympathetic denervation to the eyelid

Question 10

Define tarsorrhaphy.

Answer 10

A surgical procedure in which the eyelids are sutured together

Question 11

Define tarsus.

Answer 11

The fibrocartilaginous layer of the eyelid that contains the Meibomian glands

Question 12

Define trichiasis.

Answer 12

Hairs growing from normal skin reach the corneal and/or conjunctival surface

Question 13

What are the 4 layers to the eyelid?

Answer 13

Skin
Muscle
Tarsus and Meibomian glands
Conjunctiva

Question 14

What does the orbicularis oculi do?

Answer 14

Closes the eyelids like a zipper
CN 7
Dysfunction will cause lagophthalmos

Question 15

What does the levator palpebrae superioris do?

Answer 15

Opens the upper eyelid
CN 3
Dysfunction will cause ptosis

Question 16

What does Muller’s muscle do?

Answer 16

Opens the upper eyelid
Think Horner’s syndrome
General visceral efferent
Dysfunction will cause ptosis

Question 17

What are the 4 common causes of lagophthalmos?

Answer 17

Breed variation
Exophthalmos
Buphthalmos
CN 5 or 7 dysfunction

Question 18

What will secondary eye exposure due to lagophthalmos cause?

Answer 18

Exposure keratoconjunctivitis
Band keratopathy

Question 19

What is a good question to ask clients to determine lagophthalmos?

Answer 19

Does your dog sleep with its eyes open?

Question 20

What are the common clinical signs for Horner’s syndrome?

Answer 20

Miosis
Ptosis
Protrusion of the third eyelid
Enophthalmos

Question 21

What is the most common cause for Horner’s syndrome?

Answer 21

Idiopathic

Question 22

What does using dilute phenylephrine for diagnosis of Horner’s syndrome tell you?

Answer 22

Utilizes concept of denervation hypersensitivity
Post ganglionic Horner’s syndrome should partially or completely resolve in <15 mins

Question 23

What breeds are most commonly affected with trichiasis?

Answer 23

Brachycephalic breeds

Question 24

Where does the hair with trichiasis usually come from?

Answer 24

The nose

Question 25

What breed is common for disticia?

Answer 25

Cockers

Question 26

What is a common treatment for distichia?

Answer 26

Cryotherapy Multiple treatments are occasionally required

Question 27

What is a complication to cryotherapy?

Answer 27

Eyelid depigmentation Eyelid necrosis

Question 28

Where are ectopic cilia generally located?

Answer 28

12 o clock position

Question 29

What is the biologic behavior for eyelid tumors in cats and dogs?

Answer 29

Cats - most often malignant Dogs - most often benign

Question 30

What are the three common factors to consider when surgically removing canine eyelid tumors?

Answer 30

Is there irritation to ocular surface? - remove or debulk if yes Size? - Cannot take more than 1/3 without causing functional disturbance Location - involving nasolacrimal ducts or canthus

Question 31

What are the 4 key concepts for closure of eyelid margin defects?

Answer 31

Limited debridement Closure must be perfect - figure 8 suture pattern at margin Avoid full thickness suture bites The tarsus is the holding layer

Question 32

What can happen if you left a prolapsed gland of the third eyelid untreated?

Answer 32

Chronic conjunctivitis KCS

Question 33

When should be the only reason for removal of the gland of the third eyelid?

Answer 33

Neoplasia