Unit 1 - Conjunctiva and Cornea Flashcards
(159 cards)
1
Q
What are the functions of the conjunctiva?
A
Lines the eyelids and sclera and allows movements
Source of tear film mucin
Conjunctival associated lymphoid tissue
2
Q
Conjunctiva is clear, ____ tissue with thin branching _____.
A
mobile, vessels
3
Q
What are the bacterial flora of the conjunctiva?
A
Gram + aerobes
4
Q
When evaluating the conjunctiva, what should you be evaluating for?
A
Evaluate the bulbar and palpebral surfaces for injected vessels, bleeding, swelling, masses, foreign bodies, etc
5
Q
When evaluating the sclera what should you be looking for?
A
Evaluate for episcleral vessel congestion, masses, etc
6
Q
What are ways that the conjunctiva can respond to ocular or systemic disease?
A
Hyperemia, chemosis, color change, lymphoid follicles, ocular discharge
7
Q
What color change can the conjunctiva go through in cases of ocular or systemic disease?
A
Extreme pallor, icterus, and/or subconjunctival hemorrhage
8
Q
Serous ocular discharge = _________
Mucoid/mucopurulent ocular discharge = ________
Purulent ocular discharge = _________
A
epiphora
KCS
bacteria
9
Q
What can cause ‘red eye’?
A
Conjunctival hyperemia or episcleral injection
10
Q
Conjunctival hyperemia is due to (surface/deep) disease and episcleral injection is due to (surface/deep) disease.
A
surface, deep
11
Q
T/F - Primary conjunctivitis is more common than secondary
A
False - it is very rare, secondary is the most common presentation
12
Q
What can cause primary conjunctivitis?
A
Foreign bodies, infection, and/or allergies
13
Q
What is the most important step to treating conjunctivitis?
A
ID and address the underlying cause
14
Q
How is bacterial conjunctivitis treated?
A
Topical antibiotic QID - make sure to do a STT to check for KCS first
15
Q
How is conjunctivitis due to allergies or conjunctival pocket syndrome treated?
A
Topical gel lube and saline eye rinsing
16
Q
What is another term for neonatal conjunctivitis?
A
ophthalmia neonatorum
17
Q
What is neonatal conjunctivitis?
A
Infection behind closed puppy/kitten eyelids (this is prior to normal lid opening)
18
Q
How is neonatal conjunctivitis treated?
A
Separate eyelids, flush eyes, antibiotic ointment QID, +/- lube
19
Q
Benign or malignant?
Conjunctival melanoma
Hemangioma
Mast Cell Tumor
Subconjunctival fat prolapse
A
Conjunctival melanoma - malignant (not at eyelid or limbus)
Hemangioma - benign
Mast cell tumor - benign
Subconjunctival fat prolapse - benign
20
Q
How are conjunctival hemangiomas and mast cell tumors treated?
A
Excise and freeze the base
21
Q
What miscellaneous ‘disease processes’ can happen to the conjunctiva?
A
Dermoid, inflammatory nodules, foreign bodies, and KCS
22
Q
The cornea is a smooth, clear, and physically ______ window that has major ______ function.
A
tough, refractive
23
Q
‘A _____ cornea is a happy cornea’
A
moist
24
Q
What are the layers of the cornea?
A
Epithelium, stroma, Descemet’s membrane, and Endothelium
25
The corneal epithelium is \_\_\_\_\_philic and provides ______ function.
Lipophilic; barrier
26
The corneal stroma is \_\_\_\_philic, adheres \_\_\_\_\_, and is composed of collagen, keratocytes, and GAGs.
hydrophilic; fluorescein
27
Descemet's membrane is \_\_\_\_\_philic.
lipophilic
28
What is the role of the corneal endothelium?
It maintains 'dehydrated' clear cornea
29
What are the many things that can cause an abnormal corneal appearance?
Superficial vs. deep vascularization (red)
Granulation (pink)
Leukocytes (white, cream, yellow)
Corneal scarring (white/gray +/- vesses or synechia)
Corneal edema (white or blue)
Pigment (brown)
Sequestrum (brown or black)
Foreign body (dark or any color)
Rough or dull surface defects
30
Superficial or deep neovascularization?
Superficial
31
Superficial or deep neovascularization?
Deep
32
What can cause corneal ulcers?
Injury, conformational issues, eyelash disorders, and acquired conditions
33
What injuries can cause corneal ulcers?
Trauma, foreign body, chemical or thermal insult
34
What conformational issues can cause corneal ulcers?
Entropion, macropalpebral fissure, lagophtalmos, nasal fold trichiasis
35
What eyelash disorders can cause corneal ulcers?
Ectopic cilia, distichia (rarely)
36
What acquired conditions can cause corneal ulcers?
Keratoconjunctivitis sicca, facial nerve paralysis, eyelid masses, eyelid injuries, indolent ulcer, exposure, anesthesia, herpesvirus, Moraxella bovis, and others
37
A.
Ectopic cilia
38
B.
Exposure, KCS, trauma, chemical, thermal, M. bovis, etc
39
C.
Nasal fold trichiasis
40
D.
Foreign body behind third eyelid
41
E.
Entropion
42
What clinical signs are associated with corneal ulcers?
Blepharospasm
Epiphora
Rubbing at eyes
Enophthalmos
Elevated third eyelid
'Red eye'
Corneal edema, blood vessels (BV), infiltrates, melting
Corneal defect or surface irregularity
Reflex uveitis
43
What is associated with reflex uveitis?
Miosis, aqueous flare, hypopyon, fibrin, and photophobia
44
What is used to diagnose corneal ulcers?
History, complete ocular exam, fluorescein stain, +/- Rose bengal stain
45
If a corneal ulcer is present, how will fluorescein act when placed on the eye?
the stain will adhere to the exposed stroma
46
What does the Seidel test do?
It demonstrates corneal perforation or leakage
47
How does the Seidel test work?
Apply the stain (do not rinse) and then assess for aqueous leakage diluting stain as lighter green gravitational flow
48
Describe a superficial corneal ulcer.
Loss of corneal epithelium only
49
Describe a stromal corneal ulcer.
Some of the stroma is missing as well - superficial, midstromal, and deep stromal
50
What is a desmetocele?
Loss of epithelium and stroma to Descemet's membrane
51
Superficial or deep?
Superficial
52
Superficial or deep?
Deep
53
Superficial or deep?
Deep - desmetocele
54
Superficial or deep?
Deep
55
Superficial or deep?
Superficial
56
Superficial or deep?
Superficial
57
Superficial or deep?
Deep
58
Superficial or deep?
Superficial
59
Superficial or deep?
Deep
60
Superficial or deep?
Superficial
61
Superficial or deep?
Deep
62
A superficial ulcer will have a _______ corneal curvature.
normal
63
A stromal corneal ulcer will look like what on examination?
Corneal flattening or some indentation
64
A desmetocele will look like what on examination?
severe indentation (and stain + edge)
65
Simple or infected?
simple
66
Simple or infected?
infected
67
Simple or infected?
simple
68
Simple or infected?
infected - melting cornea
69
Simple or infected?
infected
70
Simple or infected?
infected
71
Simple or infected?
infected
72
Simple or infected?
unsure
73
Simple or infected?
infected - fungal
74
What are some findings consistent with ruptured ulcers?
The perforation site may be bulging
It is sealed with fibrin, blood, and iris
Other possible findings - hyphema, shallow anterior chamber, low IOP +
Seidel test
75
Treatment of corneal ulcers varies based on what?
Underlying cause, depth, chronicity, +/- infected, +/- melting
76
Treatment for simple/uncomplicated ulcers aims to do what?
Prevent infection, reduce pain, and facilitate healing
77
What is used to prevent infection in simple corneal ulcer management?
Prophylactic topical antibiotic - TID and QID
78
What are some broad spectrum topical abx options for simple corneal ulcer management?
Neomycin/PolymyxinB/Bacitracin ointment, Neomycin/PolymyxinB/Gramicidin solution, Tobramycin solution, oxytetracycline ointment
79
When is a topical ointment base abx for simple corneal ulcer management preferred?
For superficial ulcers (especially if due to KCS), conformational issues, or eyelash disorders
80
When is a drop abx preferred for simple corneal ulcer management?
When the patient is incooperative
81
What can be used to reduce pain in simple corneal ulcer management?
Topical atropine 1% solution or ointment - SID-BID or systemic NSAID or gabapentin
82
What is used to facilitate healing in simple corneal ulcer management?
E-collar +/- ophthalmic lubricant
83
When should simple corneal ulcers be rechecked?
in 3-5 days
84
If a simple corneal ulcer does not heal within 7-10 days, what may that mean?
The underlying cause persists, the ulcer is infected, it is an indolent ulcer
Change the diagnosis not the antibiotic
85
What diagnostic testing can be done for complicated corneal ulcers?
Culture and sensitivity and/or cytology
86
What are the preferred abx for gram + infected complicated corneal ulcers?
Chloramphenicol or fortified 5% cefazolin
87
What are the preferred abx for gram - infected complicated corneal uclers?
Aminoglycosides - Tobramycin
Fluoroquinolons - Ciprofloxacin (good gram + coverage also)
88
How often should abx be given for infected complicated corneal ulcers?
Initially every 1-2 hours, then every 4 hours if not worsening
Minimum of 6x per day
89
How are complicated corneal ulcers due to reflex uveitis treated?
Atropine drip SID-BID, oral NSAID +/- gabapentin
90
What should be used to treat melting ulcers?
Anticollagenases
91
What is the preferred anticollagenase for melting ulcers?
Serum/plasma given every 1-2 hours
Other options: EDTA, N-acetylcysteine, tetracycline abx
92
What novel ulcer therapy option promotes healing of severe and melting ulcers, is helpful with complicated and neurotrophic ulcers, and is given TID?
Vetrix Eye Q Amniotic Eye Drop
93
What systemic antibiotics can be given for complicated corneal uclers? What is the caveat to using systemic antibiotics?
Clavamox or Doxycycline
Only aids ulcer if vascular supply is present
94
What is contradicted for treatment of corneal ulceration?
Topical steroids, topical nonsteroidals, or topical anesthetics (only okay for initial exam)
95
When is surgical treatment of complicated corneal ulcers warranted?
If midstromal or deeper, worsening condition, or prolonged pain
96
What are the surgical options for complicated corneal ulcers?
Corneal cross-linking, conjunctival graft, collagen graft, corneaconjunctival transposition, and corneal transplant
97
What should be avoided surgically when treating corneal ulcers?
Third eyelid flap or temporary tarsorrhaphy
98
What are the advantages to surgical treatment of corneal ulcers?
More thorough ulcer debridement
Immediate tectonic support
Possible blood supply
Faster healing
Less aggressive medical therapy needs
99
What are the disadvantages to surgical treatment of corneal ulcers?
Requires general anesthesia
Potentially more scarring
Added expense
100
What are some other names for indolent ulcers?
Refractory ulcer, Boxer ulcer, and SCCED
101
What is an indolent ulcer?
Superficial ulcer with loose epithelial edges
102
What is the signalment for indolent ulcers?
middle-aged to older dogs
103
How is an indolent ulcer diagnosed?
Signalment, history of failed healing with appropriate therapy and no infection or other persisting cause, and the classical appearance
104
What is the classical appearance of indolent ulcers?
Epithelial defect only, loose margins, and does not extend into the stroma
105
How can an indolent ulcer be treated?
Thorough debridement with cotton-tipped applicators
Keratotomy
Superficial keratectomy (most effective)
106
What are the general non-surgical management methods for indolent ulcers?
Standard ulcer medications (topical antibiotic, atropine, and pain control) and E-collar
107
What are some additional optional therapies (non-surgical) to treat indolent ulcers?
Contact lens, tetracycline antibiotic, serum QID, 5% NaCl TID, and PSGAGs QID
108
When should indolent ulcers be rechecked after treatment has been initiated?
10-14 days +/- repeat
109
IF there is severe vascularization, what can be added to the treatment protocol for indolent ulcers?
Cyclosporine or tacrolimus BID
110
Corneal foreign bodies are commonly what?
Plant material
111
If a corneal foreign body is superficial, how should it be treated?
Apply a topical anesthetic and remove with hydropulsion or cotton swab
112
If there is a deep or penetrating corneal foreign body, what should be done?
REFER
113
After removal of a corneal foreign body, what should be done treatment-wise?
Treat as a corneal ulcer
Topical abx 4-6x/day
Topical atropine solution SID-BID
Systemic NSAID and/or gabapentin PO
E-collar
114
What is chronic superficial keratitis also known as?
Pannus
115
What is the signalment for chronic superficial keratitis?
German shepherd type breeds and Greyhounds
Young adult to middle-aged
116
What is chronic superficial keratitis?
Progressive inflammatory disease of the cornea and conjunctiva
Usually bilateral +/- symmetrical, immune-mediated, and there is a UV light factor
117
What clinical signs are associated with chronic superficial keratitis?
Corneal neovascularization, pigmentation, and scarring
Starts laterally and moves medially across the cornea
Can cause blindness +/- thickened and depigmented third eyelid
118
What is atypical pannus (plasmoma)?
Chronic superficial keratitis with third eyelid involvement without corneal change
It is a lymphocytic-plasmacytic conjunctivitis
119
What does plasmoma look like?
There is a depigmented margin of the third eyelid and a thickened, cobblestone surface
120
How is chronic superficial keratitis diagnosed?
Signalment and appearance
No other cause of CS (rule out KCS)
Cytology
121
How is chronic superficial keratitis treated?
Topical steroid QID x 2-4 weeks with tapering
Topical cyclosporine or tacrolimus BID (taper to SID)
Reduce UV exposure
Client education
+/- Lifelong therapy
122
What topical steroid is recommended for chronic superficial keratitis management?
Prednisolone acetate or dexamethasone
123
What is the physiologic cause of exposure keratitis?
A disorder of tear coverage or distribution
124
What are the corneal manifestations of exposure keratitis?
Roughened corneal surface, corneal edema, vascularization, pigmentation, scarring, and corneal ulceration
125
What are the many possible causes of exposure keratitis?
Exposure during anesthesia, eyelid deformaties, facial nerve paralysis, macropalpebral fissure, lagophthalmos, exophthalmos, buphthalmos, proptosis
126
How is exposure keratitis diagnosed?
Complete ophthalmic examination - CN testing, baseline diagnostic tests, assess eyelid apposition and closure, corneal status, and globe retropulsion
127
How is exposure keratitis managed?
Ocular lubrication, therapy based on causative agent, and prevention of further corneal changes and vision loss
128
In what breed group is pigmentary keratitis common in?
brachycephalic dogs
129
What is pigmentary keratitis a response to?
chronic irritation or inflammation
130
What are possible underlying causes of pigmentary keratitis?
KCS, chronic superficial keratitis, chronic ulcerative disease, hairs rubbing cornea, and lagophthalmos
131
How is pigmentary keratitis diagnosed?
Signalment and pattern and adnexal exam
132
What medications can be used to treat pigmentary keratitis?
Lube and cyclosporine or 0.5% tacrolimus (preferred) BID
Topical steroids if BV present and NO ulcer risk
133
What surgeries can be used to treat pigmentary keratiits?
Cryotherapy or strontium beta-irradiation to thin pigment
Keratectomy if blinded
134
What is corneal dystrophy?
An inherited, nonpainful, bilateral central/paracentral opacification
135
T/F - Corneal dystrophy is an age related change that affects vision
False - it is not age related and does not affect vision
136
When maginifying the cornea of a patient with corneal dystrophy, what does it reveal?
Sparkling corneal opacities
137
What is juvenile corneal dystrophy?
Congenital subepithelial faint opacities of the cornea that are hazy, grayish-white, mosaic and usually located in the interpalpebral fissure
138
T/F - Juvenile corneal dystrophy is nonpainful and no treatment is needed.
True - it should resolve by ~10 weeks of age
139
What is corneal degeneration?
Corneal opacities with other ocular/intraocular pathology
140
\_\_\_\_\_\_\_\_\_\_\_ exacerbate deposition in patients with corneal degeneration.
Corticosteroids
141
How can corneal degeneration result in a corneal ulcer?
The dense mineral plaques may slough resulting in a corneal ulcer
142
How is corneal degeneration managed?
Address underlying issues, +/- topical EDTA 1-2% BID-QID to bind calcium, +/- keratectomy and corneal/conjunctival graft
143
What are some other less common corneal opacifications?
\*Not on test\*
Perilimbal lipid deposits, superficial punctate keratopathy, lipid keratopathy, macular corneal dystrophy, florida spots, and infectious crystalline keratopathy
144
How are perilimbal lipid deposits diagnosed?
\*Not on test\*
labwork with a thyroid panel
145
In what breeds is superficial punctate keratopathy common in?
\*Not on test\*
Shelties and Daschunds
146
Superficial punctate keratopathy is (painful/nonpainful) +/- fluorescein stain uptake.
\*Not on test\*
painful
147
How is superficial punctate keratopathy treated?
\*Not on test\*
Topical cyclosporine BID long-term
148
What causes lipid keratopathy?
\*not on test\*
Corticosteroid use
149
In what breeds is macular corneal dystrophy common in?
\*not on test\*
Labradors
150
Where (geographically) are Florida spots common in?
\*not on test\*
Tropical and subtropical areas
151
How is infectious crystalline keratopathy treated?
\*Not tested\*
BV or surgery
152
What is endothelial dystrophy?
Endothelial cell loss of the cornea
153
What clinical signs are associated with endothelial dystrophy?
Corneal edema that starts laterally, progresses and intensifies, and is bilateral but commonly not symmetrical initially
It is not painful unless ulcers are present
154
T/F: Endothelial dystrophy is acquired.
False - it is inherited most often in Boston terriers, dachshunds, and chihuahuas
155
What is endothelial degeneration also known as?
Old dog disease
156
What clinical signs are associated with endothelial degeneration?
corneal edema with possible bulla formation that can lead to recurrent ulcers and discomfort
157
What is the preferred medication for endothelial dystrophy or degeneration management?
5% NaCl ointment TID + abx if ulcers are present
158
What is the preferred surgical treatment for endothelial dystrophy or degeneration? Other options?
Preferred - thin conjunctival graft (Gunderson flap)
Other - thermokeratoplasty, corneal transplantation, Descemet's stripping endothelial keratoplasty (best option for repaired vision, but is being investigated)
159
What are some 'other' corneal pathologies that were not discussed?
Epithelial inclusion cyst, dermoid, leukoma, and nodular granulomatous episclerokeratitis
