Conditions of the Lacrimal Secretory & Excretory Systems

Question 1

what are the functions of membrane-bound mucins?

Answer 1

prevent pathogen penetrance and enhance aqueous coherence

Question 2

what are the functions of the secretory mucins of the tear film?

Answer 2

remove debris, hold fluid in place and bind

defence molecules

Question 3

what tear proteins are found in the aqueous layer?

Answer 3

secretory IgA, IgG, IgM, albumin, lysozyme, lactoferrin, lipocalin, epidermal growth factor, transforming growth factors and interleukins

Question 4

The glycocalyx:

a. is produced by the meibomian glands in the eyelid margins
b. is an antimicrobial protein that binds and destroys bacteria
c. is an immune protein found in the aqueous portion of the tear film
d. allows binding of the tear film mucins to the corneal epithelial cells

Question 4

The glycocalyx:

a. is produced by the meibomian glands in the eyelid margins
b. is an antimicrobial protein that binds and destroys bacteria
c. is an immune protein found in the aqueous portion of the tear film
d. allows binding of the tear film mucins to the corneal epithelial cells

Answer 4

d. allows binding of the tear film mucins to the corneal epithelial cells

Question 5

Meibomian glands produce:

a. tear film immune proteins
b. tear lipids
c. tear mucins
d. aqueous tears

Answer 5

b. tear lipids

Question 6

Keratoconjunctivitis sicca is diagnosed by the presence of compatible clinical signs and a Schirmer Tear Test (STT-1) reading of:

a. >15mm/min
b. <15mm/min
c. <10mm/min
d. <5mm/min

Answer 6

c. <10mm/min

Question 7

Rose Bengal will stain a cornea when:

a. pathogenic bacteria are present
b. tear film lipid is absent
c. tear film mucin is absent
d. the Schirmer tear test is <5mm/min

Answer 7

c. tear film mucin is absent

Question 8

The lacrimal gland is innervated by:

a. sympathetic nerve fibres running with the optic nerve
b. parasympathetic nerve fibres running with the facial nerve
c. sympathetic nerve fibres running with the oculomotor nerve
d. parasympathetic nerve fibres running with the oculomotor nerve

Answer 8

b. parasympathetic nerve fibres running with the facial nerve

Question 9

Drug-associated keratoconjunctivitis sicca has been reported with:

a. oral sulphonamides
b. oral carprofen
c. topical pilocarpine
d. oral cyclosporine

Answer 9

a. oral sulphonamides

Question 10

The Jones 1 test is a test of:

a. tear film mucin presence
b. lacrimal gland innervation
c. corneal sensation
d. nasolacrimal patency

Answer 10

d. nasolacrimal patency

Question 11

Dacryops is:

a. a cyst of the nasolacrimal duct
b. a cyst of lacrimal gland secretory tissue
c. a cyst of the canaliculus
d. a cyst of the maxillary bone

Answer 11

b. a cyst of lacrimal gland secretory tissue

Question 12

The most common cause of nasolacrimal system obstruction in the cat is:

a. symblepharon obstruction of the nasolacrimal punctae
b. atresia of the nasal punctum
c. foreign body obstruction of the nasolacrimal duct
d. atresia of the nasolacrimal duct

Answer 12

a. symblepharon obstruction of the nasolacrimal punctae

Question 13

Third eyelid gland surgical excision is indicated in:

a. gland prolapse
b. gland neoplasia
c. chronic epiphora
d. scrolled cartilage

Answer 13

b. gland neoplasia

Question 14

LIST the 4 main clinical benefits of topical cyclosporine for canine ocular surface disease

Answer 14

1. reduces immune-mediated inflammation within lacrimal gland (improved aqueous tear production)
2. increased mucin production (improved tear film quality)
3. direct lacrimal stimulation
4. reduces immune-mediated inflammation in cornea (e.g. chronic superficial keratitis, eosinophilic keratitis) and conjunctiva (e.g. eosinophilic conjunctivitis)

Question 15

list 5 uses of fluorescein

Answer 15

1. Stain corneal ulceration
2. Tear film break up test (TFBUT)
3. Jones test – for nasolacrimal patency –
4. Seidel test - for aqueous leakage from a corneal perforation
5. Fluorescein angiography – to assess vascular abnormalities (usually retinal but can also be iris)

Question 16

List the causes of keratoconjunctivitis sicca in domestic species (12)

Answer 16

1. Congenital alacrima
2. Congenital KCS (in conjunction with ichthyosiform dermatosis in Cavalier King Charles spaniel (CKCS) dogs
3. Immune-mediated KCS
4. Neurogenic KCS
5. Drug-induced KCS
6. Irradiation
7. Secondary to metabolic disease (diabetes mellitus, hypothyroidism)
8. Trauma/inflammation of lacrimal gland, orbit, or innervation
9. Canine distemper virus
10. Chronic blepharoconjunctivitis
    Iatrogenic KCS (excision of third eyelid gland)
11. Symblepharon or conjunctival swelling (ductule obstruction) due to FHV-11.

Question 17

what does STT 1 measure?

Answer 17

the tear lake, and both basal tear

production and reflex tear production

Question 18

list 6 breeds predisposed to KCS in the UK

Answer 18

West Highland white terrier 
English cocker spaniel 
English bulldog
Lhasa Apso
English springer spaniel 
Toy poodle

Question 19

what is the most common cause of KCS in cats?

Answer 19

FHV1 virus

Question 20

give two important bacterial isolates in dacryocystitis in rabbits

Answer 20

staphylococcus and pasteurella

Question 21

how thick is the pre-ocular tear film?

Answer 21

-10um