Ophthalmology Flashcards
1
Q
What structures does the uvea contain?
A
Ciliary body
choroid
iris
2
Q
Describe the pupil constrictor muscle.
A
Circular
PARASYMP
3
Q
Describe the pupil dilator muscle
A
Radial
SYMP
4
Q
What should be done befroe clipping the periocular region?
A
Fill eye with gel
5
Q
What should the periorbital area be scrubbed with?
A
Povidone-iodine
6
Q
What suture material and size should be used for eye surgery?
A
5-0 or 6-0 vicryl
7
Q
What is Districhiasis?
A
Hairs growing at an abnormal site in tarsal plate and emerging at lid margin.
8
Q
What are the 4 Tx options for districhiasis?
A
Plucking
Electrolysis
Cryo
Tarsoconjunctivial resection
9
Q
What are ectopic cilia?
A
Hair which emerge from the conjunctival surface and impinge directly on the eye.
VERY PAINFUL!
10
Q
Out of districhiasis and ectopic cilia - which can cause ulcers?
A
Ectopic cilia
11
Q
What is entropion?
A
Inward rolling of lid margin
12
Q
What may occur as a result of chronic entropion? Tx?
A
large masses of granulation tissue on eye
Tx: resolve entropion
13
Q
Which procedure is used to relieve entropion?
A
Hotz-Celsus
2mm from lid margin
14
Q
What can be done to relieve entropion in young dogs?
A
Tacking procedure - other surgery done too young will over-correct!
15
Q
What is ectropion?
A
Outward turning of the lid margin - conjunctival exposure present
16
Q
What painful condition is common in middle aged cocker spaniels? Tx?
A
Upper Lid Trichiasis (highly uncomfortable)
Stades procedure
17
Q
What is the most common eyelid tumour in the dog and how does it behave?
A
Sebaceous adenoma
Benign
18
Q
Which suture pattern, used for first knot in eyelid surgery, prevents knots catching the eye?
A
Figure of 8 knot
19
Q
What is “cherry eye”?
A
Prolapse of the nictitans gland
20
Q
Whcih dog breeds are predisposed to cherry eye?
A
Mastiffs and Bulldogs
21
Q
What are the 2 options for fixing cherry eye?
A
Pocket Technique**
Gland excision
22
Q
when is the only occasion where 3rd eyelid removal is acceptable?
A
Neoplasia
23
Q
What can be used to treat conjunctivitis caused by staphs?
A
Isathal (fucidic acid)
24
Q
Which glands produce a lipid film for the eye?
A
Tarsal
25
Which glands produce an aqueous film for the eye?
Lacrimal/nictitans
26
Which glands produce a mucus film for the eye?
Conjunctival goblet cells
27
What is the most common cause of dry eye in the dog?
IM inflammation
| KCS
28
What are the clinical signs of dry eye?
```
Chronic conjunctivitis
Dull ocular srface
Mucopurulent discharge
Discomfort
Corneal ulceration
```
29
Which ABs can cause dry eye?
Sulphonamides
| Salazopyrin
30
How can we quantify tear production? Normal result?
Schirmer Tear Test
20+/-5 mean
10-15 moderate dry
<10 severely dry
31
Which drugs are a useful tear stimulant in dry eye cases?
Optimmune (cyclosporin)
| Tacrolimus ointment
32
Name a tear film replacement used in dry eye cases.
Carbomer Gel (+/- lipid)
33
how can you test the eye for adequate drainage?
Fluorescin drainage test - should come out nose in 3-4min
34
What is a corneal ulcer?
Full thickness defect in ocular epithelium
35
What is the worry with corneal ulcers?
Stroma below epithelium susceptible to keratomalacia by Gram-ve bacteria and inflammation
36
Why is flushing after applying fluorescin essential?
To remove it from old ulcers and avoid false +ves
37
If there is a non-staining area in an ulcer, what does this indicate?
DEEP - exposure of descemets membrane
38
Which breed are predisposed to indolent ulcers?
Boxers
| also corgis and staffies
39
What is the best method for Tx of corneal ulcers?
AB (gent/ciproflox/oflox)
Lubrithal
Atropine 1 drop
40
Which 2 drugs should NOT be used on eye ulcers?
NSAIDs
| Steroids
41
What are the 2 surgical techniques used to fix corneal ulcers?
Conjunctival Pedicle Graft
| Corneal-conjunctival transposition
42
How do indolent ulcers present?
Epithelial involvement only - mild oedema and loose, under-run edges
43
How are indolent ulcers treated?
Local + sedation
Scalpel
Grid keratotomy
Topical AB + lubricant
44
What is the best equipment for removing thorns?
2 needles
45
Which congenital ocular malformation are french bulldogs predisposed to?
Dermoids
46
What is pannus?
Inflm and vasc tissue advances accross the cornea from VL direction
47
How is pannus Tx?
Topical cyclosporine/tacrolimus
| or steroids
48
What are the 3 mainstays of Tx for uveitis?
Mydriatics (pain & dec adhesion)
Topical Steroids (dec inflm)
Oral NSAIDs
49
What happens if anterior uveitis is left untreated?
Extensive posterior synechiae & iris convexity (iris bombe)
w/cataract and glaucoma
50
Define Glaucoma
Abnormal rise in IOP
51
What causes glaucoma?
problem of flow or drainge NOT production
52
Why is glaucoma serious?
VERY painful
| Destroys optic nerve and retina
53
What are the signs of acute glaucoma?
```
Red eye
Pain
Steamy Cornea
Non-responsive pupil
Blind (reversible)
Globe hard & normal size
```
54
What are the signs of chronic glaucoma that are not seen in acute cases?
Variable Pain
Chronic corneal opacity
Blind (irreversible)
Globe enlarged
55
What causes primary closed angle glaucoma?
Bilateral Congenital developmental abnormality of drainage angle - decompensates suddenly in middle age
56
Which breeds are most commonly affected by 1e closed angle glaucoma?
```
Springers
Cockers
Golden/Flat coat retriever
Basset
GRT Dane
```
57
What does tonometry assess?
IOP
58
What does Gonioscopy assess?
Drainage angle
59
What are the 3 topical Tx for glaucoma?
Carbonic Anhydrase inhibitors (trusopt/azopt)
Prostaglandin analogues (lantaprost, xalatan, travatan, lumigan)
Beta Blockers (timolol)
60
How do CAIs treat glaucoma?
reduce production
61
How do PG analogues treat glaucoma?
inc outflow
62
What is the underlying cause of primary lens luxation?
Insidious degen of apparatus supporting the lens
63
Which breed is HIGHLY prone to lens luxation
Jack Russell Terrier (JRT)
64
Which approach is best to spot an anterior lens luxation?
Look and illuminate from ALL directions
65
What are the best 2 Tx options to give to a luxated lens pre-surgery?
Antibiotic/steroid combo drops (maxitrol)
Trusopt/azopt topically
66
What are the surgical options for an anterior luxated lens?
Surgical Removal
| Return it to posterior chamber via external manipulaiton + miosis
67
What are the surgical options for a subluxated lens?
Surgical Removal
| Miosis w/ PG analogues to prevent anterior dislocation
68
What is a cataract?
Any abnormal opacity in the lens
69
What is the effect of cataracts on the light reflex?
NONE
70
How are diabetic cataracts treated surgically?
Phacoemulsification (US to break up cataract and aspirate fragments)
71
What is nuclear sclerosis?
NORMAL condensation of the lens with age - blue/hazy
72
What is asteroid hyalosis?
Snowstorm in vitreous
73
What does hyperreflectivity indicate?
Tapetum being visualised via a THINNED retina
74
What is Generalised Progressive Retinal Atrophy?
Adult onset progressive retinal degeneration - results in total blindness
75
Which breeds are predisposed to GPRA?
English Cocker
Mini poodle
Labrador
76
What can be seen on fundic exam of a dog with GPRA?
Hyperreflectivity
| Vascular Attenuation
77
What is a collie eye abnormality?
Pale area lateral to optic disc w/abnormal blood vessels
78
How does hypertension cause ocular problems?
Retinal and choroidal vascular lesions and detachment
79
what is post-inflammatory retinopathy?
Hyperreflective retinal scars due to (presumed) resolved inflammation
80
Which dog breed is particularly predisposed to excessive myelination of the optic head?
Golden retievers
81
What 3 things may cause abnormal optic disc swelling?
Optic Neuritis
Meningitis
Raised ICP
82
What causes a gradual painless displacement of the globe?
Orbital tumours
83
What imaging modalities are most effective for orbital tumours?
CT/MRI
84
How should a prolapsed globe be treated?
Replace
Suture closed 2w - dont let suture rub cornea!!
Antibiotics and NSAIDs
85
What is the most effective form of pain relief/minimising complications following a globe protrusion?
Enucleation
86
What is the most common surgical approach for an enucleation?
Trans-palpebral: close to sclera!
87
What is the most frequent periorbital tumour in cats?
SCC - nodular or erosive
88
How is chlamydophila felis treated?
Doxycycline OR
| Synulox
89
What is symblepharon?
Permanent adhesion of ocular surfaces following herpesvirus infection of kittens
90
What is a corneal sequestrum? (fe)
Delayed healing of ulcer --> necrosis of exposed stroma
91
What are the 2 tx options for corneal sequestrum?
1. Slough and heal - no surgery req
| 2. Surgery +/- graft
92
What is the most common form of feline uveitis and which cats are most affected?
Lymphoplasmacytic uveitis
Old males w/street history
93
What are the 2e changes associated with lymphoplasmacytic uveitis?
Cataract
Glaucoma
Lens Luxation
94
What are the clinical signs of feline LPC uveitis?
spots/sheets of exudate on posterior cornea
prominent BVs on iris surface
Grey nodules in iris
Vitreous opacities
95
What is the most common form of ocular melanoma in the cat?
Diffuse uveal anterior melanoma
96
How can you differentiate between benign pigmentation of the eye and uveal melanoma in cats?
Thickening = melanoma
97
What is pathognomonic for hypertension in the eye of a teenage cat with no trauma Hx?
Hyphaema
98
Which cat breeds are predisposed to pan-retinal atrophy?
Siamese
| Balinese
99
Overdose with which AB may cause a rapid irreversible blindness in cats?
Baytril
100
How should the traumatised feline eye be treated
LOCAL + wait
Flush eye
Topical + oral ABs
Mydriatics
101
What must you be wary of when performing an enucleation on a cat?
excessive traction = damage nerve at chiasm = blindness!
102
Which bacteria is repsonsible for tear duct infections in the rabbit?
Pasturella
103
Why must we be careful when performing an enucleation in rabbits?
Can cause sudden, profuse, fatal haemorrhage from orbital sinus - MUST work close to sclera!
