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Flashcards in The wet eye Deck (60):
1

Define epiphora

wet face due to tearing, doesn't indicate cause, simply an overflow of tears, 2 categories:
- lack of drainage through nasolacrimal apparatus
- irritation --> reflex tearing

2

What should epiphora investigation focus on?

1. blockage
2. irritants

3

Location - lacrimal gland

under the dorsolateral orbit, 70% tears

4

What do the lacrimal puncta lead to?

a canaliculus on each side --> NSLD (intraosseous, potential additional duct openings e.g. nasopharynx)

5

Describe NSLS in rabbits

- single, large punctum in medial conjunctiva of lower eyelid
- runs in close proximity to root of primary maxillary incisor
- bends over root
- important site for NLD blockage when there are tooth problems

6

Where does the nasal punctum end?

lateral nasal wall

7

Outline NSLS in horses

- like in cats/dogs
- BUT have large, visible nasal punctum (retrograde cannulation possible)

8

Causes - delayed appearance of fluorescein for jones' test

- opening onto nasopharyngeal area
- partial blockage possibly

9

Absence of fluorescein at nasal planum for jones test indicates

strongly suspicious of blockage but not proof

10

What should you do with absent or delayed fluorescein appearance in the jones test?

flush with a disposable cannula (cats ==22gz, dogs = 26gz), alternatively use a small IV catheter without the stylette

11

Risks of flushing the NSLS after Jones test

1. damage to NSLS
2. pain during flushing (TA always proxymetacaine, sedate for some dogs/cats, probably all horses, may require GA, don't force fluid, 'pulse' it
3. aspiration of fluid (avoid inadvertant aspiration into nasopharynx, severe --> aspiration pneumonia, ensure nose tilted down, especially if sedated, OR if GA place an ETT with a cuff)

12

Causes - blocked punctum/puncta

- CONGENITAL: uni or bilateral, upper/lower, may also affect canaliculi (dysplasia or aplasia)
- POST-INFLAMMATORY/TRAUMATIC: hx of previous dz/trauma, look for clues (scars), might affect rest of NSLS

13

Tx - blocked punctum/ puncta

Cannulate other punctum, ipsilaterally if possible, irrigate pulsating fluid gently, find a pulsating bulge in conjunctiva, if confirmed, gently cut into it with tip of an 1--blade, may leave or continue with suture cannulation (GA), check other side.
- Under Sd, TA, GA or GA/TA
- if cannulation through punctum not possible, try retrograde cannulation (larger dogs, difficult, requires GA), consider further investigation (dacryoscystorhinography with xray or CT study)

14

What is dacryoscystorhinography?

In the nasal cavity where there is space in the NSL duct, put contrast in then image with xrays or CT

15

Tx - blockage of (nasolacrimal duct) NLD in the interosseous part

- more difficult
- manual expression by gentle massage
- explore with sx
- imaging to help dx
- cannulate with suture, tie to skin, both ends, leave 14 d so epithelial cells grow round it.

16

Sources of irritants causing epiphora

1. ocular surface (eyelids, TE, conjunctiva, cornea)
2. intraocular structures
3. retrobulbar area

17

Common source of pain in eyelid/ TE

ifxn or trauma

18

Describe corneal pain as a cause of epiphora

more common than eyelid/TE and potentially severe, problems with hairs, eyelid or TE, exposed corneal nn with ulcer, FB

19

What usually causes a primary eyelid/ TE problem?

trauma (especially cat claws from fights)

20

List inflammatory/ immune-mediated/infectious cuases of eyelid irritants --> epiphora

- bacteria
- mycotic (ringworm)
- parasite (demodex dogs, habronema horses)
- mediterranean countries (leishmania)
- immune-mediated (systemic problem e.g. pemphigus)

21

Define hordeolum

an internal or external stye affecting primary or third eyelid
- painful
- ifxn of glands of Zeiss or Moll (skin cilia, modified sebaceous and sweat glands) = EXTERNAL
- ifxn of meibomian glands (INTERNAL)

22

Define chalazion

= meibomian cyst
- non-painful itself but irritates cornea
- granuloma around extruded sebaceous gland material

23

What is Staphylococcal blepharitis?

= eyelid inflammation due to staph hypersensitivity
- young to young-adult
- self-harm causes most of the damage
- skin abscesses and ulcers

24

Tx - Staphylococcal blepharitis - 4

- clean, debride, lance
- protective collar to avoid self-harm (4-6 weeks)
- ABs - oral and topical (cephalosproin orally, Fucithalmic)
- Oral or injectable steroid (short term)

25

What instrument can be used to hold the eyelids open?

wire eyelid speculum

26

Tx - FB under the TE

- TA (proxymetacaine CI with ulcers, also for short term use only as epitheliotoxic)
- topical AB (chloramphenicol, Fucithalmic)
- Should heal quickly once FB removed if otherwise healthy surface and no irritants remain

27

Tx - TE trauma

- heals quickly on own if healthy
- ulcers can form
- can suture with 6-0 vicryl but debride first, magnify, small round bodied needle, requires specialist skills and equpment

28

What is 'cherry eye'?

Prolapsed gland of the TE

29

Describe cherry eye/ TE gland prolapse

- produces 30% aqueous tear film
- unilateral or bilateral
- young dogs

30

What is conjunctivitis - follicular?

- an irritant, primary eyelid / TE problem
- very common in young dogs
- allergic response to environmental allergens
- in TE mostly, eyelid side less obvious, bulbar side most obvious
- horses and stalled animals (dust, flies)

31

Tx - conjunctivitis - follicular

- avoid and protect (preservative-free, viscous, lubricant)
- topical anti-inflammatory (steroid, no AB, short term)
- sodium chromoglcate (mast cell stabiliser - tricky as must be used before degranulation)

32

List 2 primary infectious causes of conjunctivitis

- CHLAMYDOPHILA: young cats, uni/bilateral, VERY hyperemic conjunctivitis, Tx with doxycycline for 21-28d, response starts after 4-5d but don't use in pregnant queens or kittens, swab to confirm
- FHV-1: more of a cornea problem but affects conjunctiva secondarily

33

Primary infectious causes of conjunctivitis in large animals,

- IBR: signs in adults are URT red nose and ocular (redness, dryness), different signs if in utero --> ocular developmental problems
- MORAXELLA BOVIS (= pink eye): fomites, typically seasonal, very hyperemic conjunctivitis
- LISTERIA MONOCYTOGENES (= silage eye): fomites, typically seasonal

34

What is corneal LPI?

Corneal lymphoplasmacytic infiltrate = pannus = CSK = Chronic Superficial Keratitis
- causes conjunctivitis
- 2 types: cornea only, TE and cornea, TE only (= LPI of the TE, aka plasmoma)
- DOGS
* Cats = EK = eosinophilic keratitis and keratoconjunctivitis in cats*

35

Name 3 follicular problems that cause primary eyelid/ TE irritation

- distichiasis = dogs and cats
- trichiasis = breeds with prominent and hairy facial features and/or long hair near the eyes
- ectopic cilium = dogs and horses

36

Tx - trichiasis

*cut hair short*
+/- remove prominent feature if possible (nasal fold)

37

Tx - distichiasis

*electrolysis for multiple hairs
* wedge resection for single hairs

38

Tx - ectopic cilium

* wedge resection

39

Outline primary eyelid/ TE neoplasias in dogs

* commonly benign (75-90%)
- meibomian gland adenoma and papilloma are commonest
- MCTs (may be less aggressive in the eyelid)

40

Outline primary eyelid/ TE neoplasias in cats

* variable, most malignant
- SCC
- melanoma
- MCTs

41

Outline primary eyelid/ TE neoplasias in horses/cattle

* most are malignant
- sarcoid
- SCC - potentially v serious (locally recurring and mets)
- melanoma

42

Define wedge resection

= removal of a full thickness wedge of eyelid, allows for removal of small eyelid mass
- eyelid left should allow for closure without tension (i.e. up to 25% of eyelid length but variable: cocker/chihuahua, dogs/horses)

43

What is a house resection?

= a modification of a wedge resection, it allows for slightly better closure of the resections in the larger end, doesn't provide additional tissue to the eyelid, large resections will require complex reconstruction, only works in some cases, relieves tension

44

Describe the closure of a wedge resection

In two layers:
1. an internal tarsal plate suture
2. figure of 8 suture

45

What is upper eyelid agenesis?

- affects cats
- lateral upper eyelid missing (eyelid coloboma)
- leads to trichiasis
- requires reconstruction (REFER)

46

Define coloboma

a gap in part of the structures of the eye

47

List conformational problems of the primary eyelid / TE

- upper eyelid agenesis (cats)
- entropion
- ectropion

48

Where can entropion occur? (think entropion chart)

- MEDIAL LOWER EYELID +/- CANTHUS
- UPPER EYELID
- LATERAL UPPER AND LOWER EYELID AND LATERAL CANTHUS
- LATERAL LOWER EYELID

49

Which animals are prone to medial lower eyelid +/- medial canthus entropion?

- brachcepahilcs
- high prevalence in pugs

50

Which animals are prone to upper eyelid entropion?

- cockers and hounds
- heavy ears and forehead, cause in-turning of upper eyelid

51

Which dog breed suffers from lateral upper and lower eyelid and lateral canthus entropion?

Shar Peij

52

Which animals suffer from lateral lower eyelid entropion?

- young dogs of medium-big size
- young and old cats (--> fat loss --> eyes sink in)
- blepharospasm (cause/worsen entropion)

53

What can inturned hairs from eyelid cause?

ulcerative dz

54

Tx - Entropion

Celsus-Hotz
- amount to remove depends on severity (measure the pinch or roll-out method, always measure after TA to remove the spastic component)
- suture with 6-0 absorbable material following 'rule of bisection = first at either end and then half the distance until it is all closed)
- possibly with wedge resection (long eyelids leading to in-turning)

55

Tx - ectropion

possibly with wedge resection (long eyelids leading to overhanging)

56

T/F: primary eyelid/ TE repair should only be done for medical reasons

true

57

Name intraocular sources of irritants

- spasm (CB mm and iridal mm)
- miosis and photophobia
CAUSES: various intraocular dz (glaucoma, uveitis), prolonged or intense corneal stimulation causing a reflux uveitis

58

What is 'reflux uveitis'?

when iris mm go into spasm (atropine tx will help)

59

How painful is retrobulbar dz?

can be very painful

60

List examples of retrobulbar disease

- abscessatin/ cellulitis (painful)
- salivary gland disease (variably painful)
- neoplasia (rarely painful)