The Wet Eye

Question 1

What does epiphora indicate?

Answer 1

wet face d/t tearing, does NOT indicate cause

• lack of drainage
• irritation -> reflex tearing

Question 2

Which direction does blinking occour in?

Answer 2

lateral-medial brings tears to medial canthus

Question 3

Outline the nasolacrimal system

Answer 3

• inferior and superior puncta medially
• lead to canaliculus on each side
• connect to lacrimal sac
• continue as nasolacrimal duct (INTEROSSEOUS part)
• potential additional duct openings (can -> drainage into throat not nose)
• ends in nasal punctum lateral nasal wall

Question 4

How doesthe nasolacrimal system of rabbits differ to other smallies?

Answer 4

• single, large ppunctum lower lid
• nasolacrimal duct interosseous is tortuous and follows tooth roots (1* maxillary incisor) -> blockage with tooth prblems

Question 5

How does the nasolacrimal system of horses differ to smallies?

Answer 5

• large, visable nasal punctum
• cannulation of this is possible
• retrograde flushing of NLD

Question 6

What does a delayed or absence of fluorescin in the Jones test indicate?

Answer 6

• potential blockage

- indication to FLUSH and find out more

Question 7

What can damage of the NLD with a canula dispose to?

Answer 7

stricture

Question 8

What could be used instead of a nasolacrimal cannula to flush ducts?

Answer 8

• small IV caqtheter`

Question 9

Risks of flushing the nasolacrimal duct?

Answer 9

• damage and stricture-
• pain (always use topical anaesthetic proxymetacaine, do not force fluid, pulsate it)
• aspiration of fluid (tilt head down, or inflate cuff if under GA)

Question 10

Potential causes of blockage -> epiphora?

Answer 10

> imperforate punctum (congenital) 
- uni or bilateral 
- upper +- lower puncta
- may also affect caniliculi (malformation or aplasia) 
> closed puncta (2* to inflame/trauma) 
- eg. cat flu/herpes when young

Question 11

ID and Tx of puncta blockage?

Answer 11

• cannulate other punctum ipsilaterally
• pulsate fluid and look for pulsating bulge in conjunctiva
• cut if located, and place large 3-0/4-0 non absorbable suture cannulation for 14d to avoid closure
  > if cannulation not possible consider further dx
  = Dacryocystorhinography xray study with contrast
• CT with contrast

Question 12

ID and TX NLD blockage?

Answer 12

> much more difficult as interosseous 
- bulging under skin near medial canthus
- mucous production 
- surgical exploration 
- foreign material
- imagine
> cannulate with suture again

Question 13

3 main sources of pain irritants -> epiphora?

Answer 13

1. ocular surface (eyelids, TE - poss infection/trauma; conjunctiva, cornea - more common and severe, d/t hairs, eyelid, nerves exposed with ulcers, FBs)
2. intraocular structures
3. retrobulbar area

Question 14

Potential causes of 1* eyelid /TE problems

Answer 14

> trauma
inflam/immune/infectious (bacterial/mycotic/parasitic)
- leishmania
- part of systemic derm eg. pemphigus
- Hordoleum (stye) internal meibomian gland infection or external glands of Moll and Zeiss infection
- Chalazion (non painful blockage of sebaceous gland -> granuloma formation around exuded material cuasing 2* trauma to cornea)
- staphylococcal blepharitis (young/adult dogs, hypesenstivity + self harm - skin ulcers, abscesses)
- FB

Question 15

What is the tx of staphylococcal blepharaiitis?

Answer 15

• clean debride and lance
• protective collar
• Abx, cephalopsporin oral and Fucithalmic topically)

Question 16

Are long term topical local anaesthetics indicated following FB removal from under the TE?

Answer 16

No

• remove pain sensation will v tear production
• proxymetacaine is cytotoxic with prolonged use and will prevent ulcers healing

Question 17

What should be used to suture a TE trauma?

Answer 17

• 6-0 vicryl
• round bodied needle
• knots to the superficial side!

Question 18

What type of forceps are use dto handle delicate tissue?

Answer 18

• Von Graeffe

Question 19

Treatement of chery eye?

Answer 19

• prolapsed gland of TE
• produces 30% tear film so DO NOT REMOVE, also breeds pdf cherry eye pdf KCS too
• reposition using Morgans pocket technique
• if this fails anchoring techniques though these limit movement of TE so last resort

Question 20

Which dogs is follicular conjunctivitis seen more commonly? Cuases?

Answer 20

• young dogs
• allergic response to environmental allergens
• bulbar side more obvious
• seen in horses with dust/flies

Question 21

Prognosis or tx of follicular conjunctivitis?

Answer 21

• will rsolve spontaneously
• lubricant
• if persisting >6 months give topical steroids short term
• sodium chromoglycate (MC stabiliser, must be given before onset)

Question 22

What 1* infectious agents cause conjunctivitis?

Answer 22

> Clamydophila 
- young cats
- uni/bilateral 
- v hypeaemic
- Doxycyline BID for a month 
- Always Tx if suspected, can do swabs but stat tx before results if all other causes r/o. 
> FHV1
- more of a corneal problem
- affect conjunctiva 2*

Question 23

Which 1* infectious agents cause conjunctivitis in large animals?

Answer 23

> IBR
- adults: URT, red nose, ocular discharge and redness
- in utero -> ocular development problems 
> Moraxella bovis (Pink EYe) 
- typically seasonal
- fomites
- very hyperaemic conjunctivitis 
> listeria monocytongenes (Silage Eye) 
- typically seasonal
- fomites

Question 24

Which infiltrative diseases can cause 1* eyelid/TE irritation?

Answer 24

> LPI (dogs)
- aka pannus, CSK [chronic superficial keratitis], corneal LPI
- may affect cornea only, cornea and TE or TE only [plasmoma]
EK (Cats)
- easinophilic keratitis and keratoconjunctivitis
- similar pathophysiology but more eosinophils less lymphocytes

Question 25

Tx of trichiasis, distichiasis andectopic cilium?

Answer 25

• trichiasis: remove hair or prominent feature
• distichiasis: electrolysis for multiple, wedge resection for single
• ectopic cilium: wedge resection

Question 26

How does neoplasia of the eyelid differ betweenspecies?

Answer 26

> dogs
- commonly benign
- meibomian gland adenoma and papilloma
- MCT have less aggressive biological behaviour in the eyelid
> cats variable, mostly malignant
- SCC
- melanoma
- MCTs
> horses/catle, most malignant
- sarcoid
- SCC potensh v serious 
- melanoma

Question 27

How may tension on a wedge resection wound be minimised?

Answer 27

House resection - cut wedge edges parallel instead of V shaped

Question 28

How are wedge resections closed?

Answer 28

• internal tarsal plate suture

- figure of 8 suture

Question 29

What conformational problems may affect the eyelid? `

Answer 29

> upper eyelid agenisis in cats 
- lateral upper eyelid missing (eyelid coloboma) 
- leads to trichiasis
- requires reconstruction 
> entropion
> ectropion

Question 30

What is the entropion chart?

Answer 30

Awaiting email response!

Question 31

How may entropion be repaired?

Answer 31

Celsus-Hotz or Hotz-Celsus repair

• remove wedge from under eye
• suture with 6-0 absorbable material
• Rile of Bisection (start at either end then half distance until it is all closed)

Question 32

What ethics are asscoaited with conformational issues?

Answer 32

• inform owners for showing
• breeding?
• repair only for medical reasons not looks

Question 33

What intraocular sources may -> epiphora? How?

Answer 33

> glaucoma, uveitis, others
prolonged/intense corneal stimulation cuasing reflex uveitis
- spasm of ciliary and iridial musculature
- miosis and photophobia

Question 34

What is the tx of iris spasm?

Answer 34

Atropine relaxes ciliary body for ~ week

Question 35

What type of retrobulbar disease may cause epiphora?

Answer 35

• abscessation/cellulitis (painful)
• salivery gland dz (variably painful)
• neoplasia (rarely painful)

Question 36

What is reflec uveitis?

Answer 36

• chronic corneal pain d/t ulcer -> psasm of iris and ciliary body