2: Cornea Flashcards
1
Q
Bowman’s layer damage
A
- does not regenerate
- will be replaced by epithelial cells or stroma-like fibrous tissue
- however, very resistant to damage by shearing, penetration, or infection
2
Q
stromal damage
A
- leads to scarring/opacification
- newly formed connective tissue components differ slightly from original tissue; alignment and organization of collagen fibrils are not as precise
3
Q
Descemet’s membrane damage
A
- can be secreted and re-formed by stromal keratocytes and endothelium
- however, very resistant to damage by shearing, penetration, or infection
4
Q
epithelial damage
A
- heals within hours to days (turnover time for entire corneal epithelium is 7-10 days)
- if the basement or hemidesmosomes are damaged, takes months to heal completely; if hemidesmosomes are malformed, can lead to recurrent corneal erosion
- increases risk of infection due to break in epithelial barrier
- generally scar-free
- can result in mild stromal edema; loss of tight junctions between surface cells allows fluid from tear film to enter K
- if trigeminal nerve damage or limbal stem cell damage, wound healing will be impaired
5
Q
endothelial damage
A
- endothelial cells do not regenerate
- with cell loss, neighboring cells generally enlarge and flatten to cover the area of loss: results in enlarged endothelial cells (polymegathism), irregularly shaped cells (pleomorphism), and a decrease in cell density
- can result in stromal edema: loss of cells = loss of metabolic pumps; moderate to severe edema in the stroma will cause folds in Descemet’s membrane; corneal edema is directed towards posterior stroma (anterior stroma has more tightly packed lamellae of collagen making it more resistant to edema); cause Descemet’s membrane to buckle giving the appearance of vertical folds (striae)
6
Q
bacterial keratitis (microbial keratitis, corneal ulcer, bacterial ulcer)
A
bacterial infection of the cornea
7
Q
bacterial keratitis (microbial keratitis, corneal ulcer, bacterial ulcer) etiology/associations
A
corneal epithelial defect with subsequent bacterial infection:
- epithelial defect is most commonly the result of contact lens wear, particularly if extended
- epithelial defects can also occur from trauma, surgery, ocular surface disease (e.g., herpetic keratitis, dry eye, trichiasis, severe allergic eye disease, corneal anesthesia)
- most common bacteria include Staph and Strep species, Pseudomonas aeruginosa, and Moraxella catarrhalis
some bacteria can penetrate an intact cornea (no epithelial defect)
- keratitis usually occurs as a result of a severe conjunctivitis
- includes Neisseria gonorrhoeae, Neisseria meningitidis, Haemophilus influenzae, Corynebacterium diphtheriae)
8
Q
bacterial keratitis (microbial keratitis, corneal ulcer, bacterial ulcer) demographics
A
most commonly occurs in CL wearers
9
Q
bacterial keratitis (microbial keratitis, corneal ulcer, bacterial ulcer) laterality
A
unilateral
10
Q
bacterial keratitis (microbial keratitis, corneal ulcer, bacterial ulcer) symptoms
A
- red eye
- ocular pain with tearing and photophobia
- mucous discharge
- blurred vision
11
Q
bacterial keratitis (microbial keratitis, corneal ulcer, bacterial ulcer) signs
A
- conjunctival injection
- infectious corneal ulcer (stromal thinning with overlying epithelial defect and an associated stromal infiltrate): size of epithelial defect is approx. = to size of stromal infiltrate; typically located centrally or paracentrally
- stromal edema
- AC rxn (WBCs in the AC); if severe, hypopyon can form
- mucopurulent/purulent discharge
- eyelid edema in severe cases
12
Q
bacterial keratitis (microbial keratitis, corneal ulcer, bacterial ulcer) complications
A
- corneal scarring
- corneal perforation
13
Q
bacterial keratitis (microbial keratitis, corneal ulcer, bacterial ulcer) management
A
- d/c CL wear
- topical broad spectrum antibiotic(s)
- H. influenzae and N. gonorrhoeae require systemic treatment in addition to a topical antibiotic
- oral analgesic as needed
- cycloplegic for pain
- evaluate daily to monitor for improvement in s/s; improvement should occur in 24-48 hours of initiating tx with resolution in 1-2 weeks
- if not resolving with tx, ulcer larger than 2 mm or in the visual axis, consider culturing
- if not resolving with tx, consider an amniotic membrane in addition to a topical antibiotic
- if severe inflammation persists after bacterial infection is under control, consider a topical steroid
- if significant stromal thinning occurs, limit the risk of corneal perforation by treating with ascorbic acid (promotes collagen synthesis) and citric acid or a tetracycline (inhibits collagenolysis); also discuss eye protection
- if medical therapy fails, corneal perforation occurs, or there is visually significant corneal scarring, refer out for penetrating keratoplasty (PKP, full thickness corneal transplant); another option for corneal perforation is an amniotic membrane transplantation
14
Q
bacterial keratitis (microbial keratitis, corneal ulcer, bacterial ulcer) pearls:
- infectious keratitis is commonly _____; in general, corneal infections are treated as _____
- when infectious keratitis is present, check IOP ____
- with patients in significant pain from a corneal issue, consider _____, but never ___
A
bacterial;
bacterial unless high suspicion for another organism;
using non-contact method or iCare;
instilling a topical anesthetic during exam to aid in evaluation the eye;
prescribe an anesthetic for ocular pain!!!
15
Q
fungal keratitis
A
fungal infection of the cornea
16
Q
fungal keratitis etiology/associations
A
- corneal epithelial defect with subsequent fungal infection
- if filamentous fungi (e.g., Aspergillus and Fusarium species), epithelial defect is most commonly the result of trauma with vegetative matter or contact lens wear, particularly if extended
- if non-filamentous fungi (e.g., Candida species), epithelial defect is most commonly the result of ocular surface disease (e.g., herpetic keratitis, dry eye, trichiasis, severe allergic eye disease, corneal anesthesia)
17
Q
fungal keratitis demographics
A
no predilection
18
Q
fungal keratitis laterality
A
unilateral
19
Q
fungal keratitis symptoms
A
- red eye
- ocular pain with tearing and photophobia
- mucous discharge
- blurred vision
20
Q
fungal keratitis signs
A
- conjunctival injection
- infectious corneal ulcer (stromal thinning with overlying epithelial defect and an associated stromal infiltrate): size of epithelial defect < size of stromal infiltrate; infiltrate has feathery edges if filamentous fungi; typically located centrally or paracentrally
- satellite lesions surrounding the primary infiltrate
- stromal edema
- AC rxn (WBCs in AC); if severe, hypopyon can form
- mucopurulent/purulent discharge
- eyelid edema in severe cases
21
Q
fungal keratitis complications
A
- corneal scarring
- corneal perforation
22
Q
fungal keratitis management
A
- d/c CL wear
- culture to confirm diagnosis; may have bacterial co-infection
- topical anti-fungal; consider epithelial debridement to facilitate antifungal penetration
- oral antifungal in addition to topical antifungal for deep ulcers
- oral analgesic as needed
- cycloplegic for pain
- evaluate daily to monitor for improvement in s/s; stability of infection after initiation of tx is often a favorable sign; resolution may take weeks to month
- if not resolving with tx, consider an amniotic membrane in addition to a topical antifungal
- if significant stromal thinning occurs, limit the risk of corneal perforation by treating with ascorbic acid (promotes collagen synthesis) and citric acid or a tetracycline (inhibits collagenolysis); also discuss eye protection
- if medical therapy fails, corneal perforation occurs, or there is visually significant corneal scarring, refer out for penetrating keratoplasty (PKP, full thickness corneal transplant); another option for corneal perforation is an amniotic membrane transplantation
23
Q
fungal keratitis pearls:
-do not use ____ for fungal keratitis
A
topical steroids (can promote replication of microorganism)
24
Q
acanthamoeba keratitis
A
protozoal infection of the cornea
25
acanthamoeba keratitis etiology/associations
- corneal epithelial defect with subsequent acanthamoeba infection
- epithelial defect is most commonly the result of contact lens wear, particularly if extended
- infection typically occurs when a contact lens wearer uses nonsterile water to clean lenses or exposure to water while wearing contact lenses
26
acanthamoeba keratitis demographics
most commonly occurs in CL wearers
27
acanthamoeba keratitis laterality
unilateral
28
acanthamoeba keratitis symptoms
- red eye
- ocular pain with tearing and photophobia; pain is usually out of proportion to early clinical findings
- mucous discharge
- blurred vision
29
acanthamoeba keratitis signs
- conjunctival injection
- early findings: epitheliitis with pseudodendrites, whorls, epithelial ridges, and/or diffuse subepithelial microcysts; subepithelial infiltrates (SEIs)- sometimes along the corneal nerves, producing a radial keratoneuritis
- late (3-8 weeks): ring-shaped corneal stromal infiltrate
- stromal edema
- AC rxn; if severe, hypopyon can form
- minimal mucous discharge
- eyelid edema in severe cases
30
acanthamoeba keratitis complications
- corneal scarring
| - corneal perforation
31
acanthamoeba keratitis management
- d/c CL wear
- culture to confirm diagnosis; may have bacterial and/or fungal co-infection
- topical antiprotozoal; consider epithelial debridement to facilitate antiprotozoal penetration
- topical propamidine isethionate (disinfectant and antiseptic) in addition to topical antiprotozoal
- oral antifungals in addition to the above treatment have shown success
- oral analgesic as needed
- cycloplegic for pain
- evaluate daily to monitor for improvement in s/s; stability of infection after initiation of tx is often a favorable sign; resolution may take 1-12 months; tx is usually continued for 3 months after resolution of inflammation due to concern for recurrence
- if not resolving with tx, consider an amniotic membrane in addition to a topical antiprotozoal
- if sever inflammation persists after acanthamoeba infection is under control, consider a topical steroid
- if significant stromal thinning occurs, limit the risk of corneal perforation by treating with ascorbic acid (promotes collagen synthesis) and citric acid or a tetracycline (inhibits collagenolysis); also discuss eye protection
- if medical therapy fails, corneal perforation occurs, or there is visually significant corneal scarring, refer out for penetrating keratoplasty (PKP, full thickness corneal transplant); another option for corneal perforation is an amniotic membrane transplantation
32
acanthamoeba keratitis pearls:
-early misdiagnosis as _____ is relatively common; presentation of 2 disease can be quite similar in the early stages; ____ typically responds well to appropriate tx
HSV keratitis;
| HSK
33
marginal keratitis
- also called Staphylococcal Hypersensitivity, Marginal Sterile Infiltrate, and/or Marginal Sterile Ulcer
- inflammation of the peripheral cornea
34
marginal keratitis etiology/associations
- type IV hypersensitivity reaction to staphylococcal antigens
- commonly associated with chronic staphylococcal blepharitis
35
marginal keratitis demographics
typically occurs between the ages of 45-65 years
36
marginal keratitis laterality
bilateral > unilateral
37
marginal keratitis symptoms
- mild red eye
- mild ocular pain with tearing and photophobia
- chronic eyelid crusting and dryness from blepharitis
38
marginal keratitis signs
- sectoral conjunctival injection (in area of infiltrate)
- stromal inifiltrate(s) (WBCs) near the limbus; infiltrates are small, round, and well defined; can coalesce and become circumferential; separated from the limbus by a clear zone
- sterile ulcer (stromal thinning with overlying epithelial defect in the area of the stromal infiltrate); size of epithelial defect < size of infiltrate
- minimal to no AC rxn
- mild pannus
- blepharitis
39
marginal keratitis complications
corneal scarring
40
marginal keratitis management
- eyelid hygiene and warm compress for blepharitis
- topical antibiotic (low dose antibiotics on the eyelids may have to be maintained indefinitely)
- if moderate to severe, topical steroid in addition to topical antibiotic
- oral doxycycline if blepharitis is refractory to eyelid hygiene and warm compress
- if patient is a CL wearer, d/c CL wear
41
marginal keratitis pearls:
- condition is generally _____
- CL wearers can develop _____
chronic and recurrent;
similar sterile infiltrates (also due to hypersensitivity rxn to staphylococcal antigens; often seen in pts who sleep in CLs; may not be a clear zone between infiltrate and limbus; most pts present with mild to no symptoms and do not come in for an exam; if active inflammation, tx includes d/c CL wear until resolution, topical lubrication, and discuss CL hygiene)
42
phlyctenular keratoconjunctivitis (phlyctenulosis)
inflammation of the cornea and conjunctiva
43
phlyctenular keratoconjunctivitis (phlyctenulosis) etiology/associations
- type IV hypersensitivity reaction to staphylococcal antigens; may also be a hypersensitivity reaction to tuberculosis
- commonly associated with chronic staphylococcal blepharitis
44
phlyctenular keratoconjunctivitis (phlyctenulosis) laterality
unilateral or bilateral
45
phlyctenular keratoconjunctivitis (phlyctenulosis) symptoms
- mild red eye
- ocular pain with tearing and photophobia
- chronic eyelid crusting and dryness from blepharitis
46
phlyctenular keratoconjunctivitis (phlyctenulosis) signs
- sectoral conjunctival injection (in area of phlyctenule)
- conjunctival phlyctneule (small, white subepithelial inflammatory nodule); at or near the limbus
- corneal phlyctenule (small, white subepithelial inflammatory nodule); juxtablimbal; migrates toward center of cornea with trail of neovascularization; may have an overlying epithelial defect
- blepharitis
47
phlyctenular keratoconjunctivitis (phlyctenulosis) complications
corneal scarring (typically in the shape of a triangle)
48
phlyctenular keratoconjunctivitis (phlyctenulosis) management
- eyelid hygiene and warm compress for blepharitis
- topical antibiotic (low dose antibiotics on the eyelids may have to be maintained indefinitely)
- if moderate to severe, topical steroid in addition to topical antibiotic
- oral doxycycline if blepharitis is refractory to eyelid hygiene and warm compress
- if patient is a CL wearer, d/c CL wear
- if suspicion for TB, order lab work
49
```
phlyctenular keratoconjunctivitis (phlyctenulosis) pearls:
-condition is generally _____
```
chronic and recurrent
50
peripheral ulcerative keratitis (PUK)
inflammation and subsequent thinning of the peripheral cornea
51
peripheral ulcerative keratitis (PUK) etiology/associations
- white blood cells release collagenase and protease that destroy corneal stroma
- collagen vascular disease and vasculitis; most common diseases include RA, SLE, GPA, PAN
- local or systemic infection; most common infections include staph, strep, gonococcal, herpes simplex, herpes zoster, lyme, syhpilis, TB
52
peripheral ulcerative keratitis (PUK) laterality
unilateral > bilateral
53
peripheral ulcerative keratitis (PUK) symptoms
- red eye
- ocular pain with tearing and photophobia
- blurred vision
54
peripheral ulcerative keratitis (PUK) signs
- sectoral conjunctival injection (in area of corneal thinning)
- crescent-shaped corneal ulceration (stromal thinning with overlying epithelial defect); juxtalimbal; may have surrounding infiltrate
- may have accompanied scleritis and/or anterior uveitis
55
peripheral ulcerative keratitis (PUK) complications
- corneal scarring
| - corneal perforation; can rapidly occur, within days
56
peripheral ulcerative keratitis (PUK) management
infectious:
- aggressive topical lubrication
- treat w/ appropriate anti-infective
- amniotic membrane to relieve symptoms and facilitate healing
non-infectious:
- aggressive topical lubrication
- topical antibiotic
- oral steroids
- oral immunosuppressants for long-term therapy
- bandage contact lens or amniotic membrane to relieve symptoms and facilitate healing
- recommend eye protection
- if etiology is unknown, order lab work based on most likely etiologies
- if systemic etiology, refer out for systemic treatment
- cyanoacrylate adhesive can arrest corneal melting
- if significant stromal thinning occurs, limit the risk of corneal perforation by treating with ascorbic acid (promotes collagen synthesis) and citric acid or a tetracycline (inhibits collagenolysis); also discuss eye protection
- if corneal perforation occurs, refer out for amniotic membrane transplantation or penetrating keratoplasty; PKP has a high failure rate due to graft melt from PUK recurrence
57
peripheral ulcerative keratitis (PUK) pearls:
- very rare
- chronic and recurrent
- _____ is most common systemic association of PUK
- ~35% of patients also have ____
- topical corticosteroids suppress corneal inflammation, but _____
- ____ is a similar condition
RA;
scleritis with necrotizing scleritis being most common;
they are usually best avoided in cases of PUK as they can contribute to corneal melt by suppressing collagen production;
Mooren's ulcer (symptoms, signs, tx are similar; idiopathic; diagnosis of exclusion)
58
Terrien's marginal degeneration
progressive circumferential thinning of peripheral cornea
59
Terrien's marginal degeneration etiology/associations
idiopathic
60
Terrien's marginal degeneration demographics
typically occurs over the age of 30
61
Terrien's marginal degeneration laterality
bilateral > unilateral
62
Terrien's marginal degeneration symptoms
- asymptomatic
| - blurred vision
63
Terrien's marginal degeneration signs
- peripheral stromal thinning; starts superiorly, spreads circumferentially
- mild pannus over the area of thinning
- irregular astigmatism
64
Terrien's marginal degeneration management
- monitor q6-12 months: slit lamp exam, photos
- recommend glasses or eye shield for protection
- correct refractive error with glasses/CLs
- watch for: corneal scarring, corneal perforation (rare; epithelium usually remains intact)
- corneal consultation when perforation seems likely or when astigmatism becomes uncorrectable
65
Terrien's marginal degeneration pearls:
| -_____ is a similar finding that occurs in the elderly
Furrow degeneration:
- non-progressive
- stromal thinning is peripheral to arcus senilis
- no tx necessary
66
keratoconus (KCN)
progressive central or paracentral (inferior to visual axis) stromal thinning accompanied by protrusion of the cornea in the area of thinning
67
keratoconus (KCN) etiology/associations
- unknown etiology
- systemic associations: Down, Ehlers-Danlos, and Marfan syndromes
- ocular associations: atopic disease (i.e., AKC), Leber congenital amaurosis, retinitis pigmentosa, chronic eye rubbing
- family hx of keratoconus in 10% of patients
68
keratoconus (KCN) demographics
typically presents during teenage years
69
keratoconus (KCN) laterality
bilateral > unilateral
70
keratoconus (KCN) symptoms
blurred vision- progressive
71
keratoconus (KCN) signs
- central or paracentral (inferior to visual axis) stromal thinning accompanied by protrusion of the cornea in a cone shape; maximal thinning at the apex of the protrusion; central or paracentral steepening on corneal topography
- progressive myopia and irregular astigmatism; scissoring reflex on retinoscopy; "egg-shaped" mires on keratometry; abnormal corneal topography
- oil-droplet reflex on retroillumination (cone-shape of the cornea produces a dark, round shadow)
- Rizutti's sign
- Munson sign
- Fleischer ring
- Vogt striae; temporarily disappear with pressure on the globe
- superficial apical scarring in advanced disease, due to breaks in Bowman's layer
72
Rizutti's sign
triangle of light on iris when penlight shined from opposite side
73
Munson sign
bulging of the lower eyelid when looking downward
74
Fleischer ring
epithelial iron deposits at the base of the cone
75
Vogt striae
fine, vertical, deep stromal stress lines
76
keratoconus (KCN) complications
corneal hydrops (influx of aqueous into the cornea due to a rupture in Descemet's membrane); symptoms include a red eye, sudden decrease in vision, pain with tearing and photophobia and signs include conjunctival injection, corneal edema, AC rxn
77
keratoconus (KCN) management
- monitor q3-12 months: corneal topography, slit lamp exam, photos
- discuss avoidance of rubbing eyes
- correct refractive error with glasses/CLs (soft, RGP, scleral)
- if CLs cannot be tolerated or produce unsatisfactory results, refer out for intracorneal ring segment transplantation or keratoplasty
- consider referral for corneal collagen cross-linking (CXL)
78
intracorneal ring segment transplantation
- must have minimum corneal thickness of 400 um, clear central cornea, and CL intolerance
- ring segments made of PMMA are implanted in deep corneal stroma
- goal is to reduce corneal irregularity and facilitate CL tolerance
79
keratoplasty
- penetrating keratoplasty (PKP)- full thickness corneal transplant
- deep anterior lamellar (DALK)- partial thickness corneal transplant (epithelium to deep anterior stroma)
- may have residual astigmatism, necessitating CL correction for optimal acuity
80
corneal collagen cross-linking
- minimum of 400 um thickness required
- large area of corneal epithelium removed, riboflavin drops instilled, exposed to UVA light x30 minutes
- goal is to "cross-link" molecular bonds in the cornea to strengthen it and slow down (ideally eliminate) progression
81
hydrops management
- treat with hypertonic saline, cycloplegic, optional large diameter BCL for comfort, and educate the patient on eye protection
- Descemet's break usually heals in 6-10 weeks, edema clears, and a variable amount of stromal scarring occurs
- to speed recovery, refer for pneumatic descemetopexy (placement of air or gas in the anterior chamber)
- if scarring occurs or becomes chronic, refer out for penetrating keratoplasty (PKP, full thickness corneal transplant)
82
keratoconus (KCN) pearls:
- most common _____
- KCN severity based on keratometry values: mild= ____, moderate= ____, severe= _____;
- ____% of patients develop hydrops
```
corneal ectasia (1 in 2000 people);
<48D;
48-54D;
>54D;
2-3
```
83
pellucid marginal degeneration (PMD)
progressive inferior peripheral stromal thinning accompanied by protrusion of the cornea above the thinned area
84
pellucid marginal degeneration (PMD) etiology/association
unknown etiology
85
pellucid marginal degeneration (PMD) demographics
typically presents during the ages of 20-40
86
pellucid marginal degeneration (PMD) laterality
bilateral > unilateral
87
pellucid marginal degeneration (PMD) symptoms
blurred vision- progressive
88
pellucid marginal degeneration (PMD) signs
- crescent-shaped band of inferior stromal thinning accompanied by protrusion above the band; band ~1-2 mm in height and ~1-2 mm from the limbus; inferior "crab claw" or "kissing doves" pattern of steepening on corneal topography
- irregular astigmatism; abnormal corneal topography
89
pellucid marginal degeneration (PMD) complications
corneal hydrops (influx of aqueous into the cornea due to a rupture in Descemet's membrane); symptoms include a red eye, sudden decrease in vision, pain with tearing and photophobia and signs include conjunctival injection, corneal edema, AC rxn
90
pellucid marginal degeneration (PMD) management
- similar to keratoconus
| - keratoplasty has a higher failure rate in PMD because it requires larger grafts
91
pellucid marginal degeneration (PMD) pearls:
| -in contrast to keratoconus, ______ do not occur
scarring, Vogt striae, and Fleischer ring
92
arcus senilis (circumsenilis, arcus)
lipid deposition in the corneal stroma
93
arcus senilis (circumsenilis, arcus) etiology
- age-related
| - in patients < 40 years, MAY be due to hyperlipidemia
94
arcus senilis (circumsenilis, arcus) demographics
typically occurs over the age of 40
95
arcus senilis (circumsenilis, arcus) laterality
bilateral
96
arcus senilis (circumsenilis, arcus) symptoms
- asymptomatic
| - may notice a gray or white ring around eye
97
arcus senilis (circumsenilis, arcus) signs
- gray to white band around the cornea
- starts as an arc superior and inferior and extends circumferentially
- separated from the limbus by a clear zone
98
arcus senilis (circumsenilis, arcus) management
- none if age-related
| - in patients < 40, order a lipid panel
99
```
arcus senilis (circumsenilis, arcus) pearls:
-most common _____
```
peripheral corneal opacity
100
crocodile shagreen
opacities in the corneal stroma; opacities are most likely vacuoles within the cytoplasm of keratocytes
101
crocodile shagreen etiology
age-related
102
crocodile shagreen demographics
typically occurs over the age of 40
103
crocodile shagreen laterality
bilateral
104
crocodile shagreen symptoms
asymptomatic
105
crocodile shagreen signs
gray or white polygonal stromal opacities separated by relatively clear spaces; starts in the peripheral cornea
106
crocodile shagreen management
none
107
limbal girdle of Vogt
elastotic degeneration at the limbus; may also have deposition of calcium
108
limbal girdle of Vogt etiology
age-related
109
limbal girdle of Vogt demographics
typically occurs over the age of 40
110
limbal girdle of Vogt laterality
bilateral
111
limbal girdle of Vogt symptoms
asymptomatic
112
limbal girdle of Vogt signs
whitish superficial band at the limbus; typically at 3 and 9 o'clock; may have chalk-like flecks (calcium)
113
limbal girdle of Vogt management
none
114
corneal dystrophies
group of genetic, inherited disorders in which there is a bilateral, progressive accumulation of deposits within corneal layers
115
epithelial basement membrane dystrophy (EBMD)
- also called Anterior Basement Membrane Dystrophy (ABMD), Map-Dot Fingerprint Dystrophy, and/or Cogan's Dystrophy
- thickening of the corneal epithelial basement membrane with absence of hemidesmosomes and deposition of fibrillary protein between the BM and Bowman's layer
116
epithelial basement membrane dystrophy (EBMD) etiology
genetic abnormality
117
epithelial basement membrane dystrophy (EBMD) demographics
typically becomes apparent during teenage years
118
epithelial basement membrane dystrophy (EBMD) laterality
bilateral
119
epithelial basement membrane dystrophy (EBMD) symptoms
- asymptomatic
- ocular irritation (e.g., burning, FBS)
- blurred vision
120
epithelial basement membrane dystrophy (EBMD) signs
- intraepithelial diffuse gray patches (maps), creamy white cysts (dots), or fine refractile lines (fingerprints) in the corneal epithelium
- negative staining with Fl due to raised areas of epithelium
121
epithelial basement membrane dystrophy (EBMD) complications
recurrent corneal erosion (RCE)
122
epithelial basement membrane dystrophy (EBMD) management
- monitor: slit lamp exam, photos
- topical lubrication (for prophylaxis of RCE)
- if significant discomfort or reduced vision, refer for superficial keratectomy or keratoplasty (superficial keratectomy= smoothing of the corneal surface by removal of epithelium down to Bowman's layer)
- treat RCE
123
epithelial basement membrane dystrophy (EBMD) pearls:
- most common _____
- ____% of patients develop RCE; accounts for ____% of RCE cases
corneal dystrophy;
~10;
~30
124
Fuch's dystrophy
accelerated endothelial cell loss with subsequent polymegathism (change in cell size) and pleomporphism (change in cell shape)
125
Fuch's dystrophy etiology
genetic abnormality
126
Fuch's dystrophy demographics
- typically becomes apparent during the ages of 45-65
| - women > men
127
Fuch's dystrophy laterality
bilateral
128
Fuch's dystrophy symptoms
- asymptomatic
| - decreased vision, worse in the morning
129
Fuch's dystrophy signs
- Guttata centrally (accumulation of collagen in Descemet's membrane; secreted by damaged endothelial cells); seen as tiny dark spots int he endothelium that progress to beaten-metal appearance
- endothelial pigment
- central stromal edema
- central epithelial edema in advanced cases
- stromal opacification in advanced cases
130
Fuch's dystrophy complications
bullous keratopathy:
- bullae (water blisters) form in the cornea as a result of severe stromal edema
- bullae may rupture (lead to an epithelial defect) and cause significant pain
131
Fuch's dystrophy management
- monitor: slit lamp exam, photos, specular microscopy, pachymetry
- to treat corneal edema: hypertonic saline (sodium chloride, Muro 128), use of hairdryer in the morning
- if ruptured bullae, treat with a topical antibiotic (for prophylaxis of bacterial infection) and BCL (for comfort) in addition to hypertonic saline
- if decreased vision, refer for keratoplasty
132
Fuch's dystrophy pearls:
- _____ can cause endothelial cell loss and worsen the condition
- _____ can be non-progressive and not cause K edema
- _____ can be a normal aging change; termed ____ and typically occur _____
```
cataract surgery;
guttata;
guttata;
Hassell-Henle bodies;
in the peripheral cornea
```
133
posterior polymorphous dystrophy (PPMD)
metaplasia (transformation of one differentiated cell type to another differentiated cell type) of endothelial cells; endothelial cells become epithelial-like (raised vs. flat and can divide)
134
posterior polymorphous dystrophy (PPMD) etiology
genetic abnormality
135
posterior polymorphous dystrophy (PPMD) demographics
typically becomes apparent during teenage years
136
posterior polymorphous dystrophy (PPMD) laterality
bilateral > unilateral
137
posterior polymorphous dystrophy (PPMD) symptoms
- asymptomatic
| - decreased vision
138
posterior polymorphous dystrophy (PPMD) signs
- classic vesicle-like lesions in posterior cornea (circular or oval transparent cysts with a gray halo)
- band lesions (AKA snail tracks) in posterior cornea (horizontal lesions with parallel, scalloped edges)
- stromal edema is rare
139
posterior polymorphous dystrophy (PPMD) complications
secondary open angle glaucoma; corneal endothelial cells may migrate over the TM and impair aqueous outflow
140
posterior polymorphous dystrophy (PPMD) management
- monitor q6-12 months (slit lamp exam, photos, IOP, gonio, ON photos, ON OCT, GCC, VF)
- if glaucoma develops, tx is similar to POAG
- if decreased vision, refer for keratoplasty
141
Meesman epithelial dystrophy
thickening of the corneal epithelial basement membrane with epithelial cysts filled with cellular debris
142
Meesman epithelial dystrophy etiology
genetic abnormality
143
Meesman epithelial dystrophy demographics
typically becomes apparent in 1st decade
144
Meesman epithelial dystrophy laterality
bilateral
145
Meesman epithelial dystrophy symptoms
- asymptomatic
| - blurred vision
146
Meesman epithelial dystrophy signs
tiny intraepithelial vesicles in the interpalpebral zone extending limbus to limbus
147
Meesman epithelial dystrophy complications
RCE
148
Meesman epithelial dystrophy management
- monitor (slit lamp exam, photos)
- topical lubrication (for prophylaxis of RCE)
- if significant decrease in vision, refer for superficial keratectomy or keratoplasty
- treat RCE
149
Reis-Bucklers corneal dystrophy
hyaline-like deposits accumulate in Bowman's layer and anterior stroma; stain red with Masson's trichrome stain
150
Reis-Bucklers corneal dystrophy etiology
genetic abnormality
151
Reis-Bucklers corneal dystrophy demographics
typically becomes apparent in 1st decade
152
Reis-Bucklers corneal dystrophy laterality
bilateral
153
Reis-Bucklers corneal dystrophy symptoms
- asymptomatic
| - blurred vision
154
Reis-Bucklers corneal dystrophy signs
irregular, gray-white, reticular opacities; initially in Bowman's layer and anterior stroma centrally; progress to deeper stroma sparing the periphery
155
Reis-Bucklers corneal dystrophy complications
RCE
156
Reis-Bucklers corneal dystrophy management
- monitor (slit lamp exam, photos)
- topical lubrication (for prophylaxis of RCE)
- if significant decrease in vision, refer for keratoplasty
- treat RCE
157
Thiel-Behnke corneal dystrophy
curly collagen fibrils accumulate in Bowman's layer and anterior stroma
158
Thiel-Behnke corneal dystrophy etiology
genetic abnormality
159
Thiel-Behnke corneal dystrophy demographics
typically becomes apparent in 1st decade
160
Thiel-Behnke corneal dystrophy laterality
bilateral
161
Thiel-Behnke corneal dystrophy symptoms
- asymptomatic
| - blurred vision
162
Thiel-Behnke corneal dystrophy signs
irregular, gray-white, honeycomb-like opacities; initially in Bowman's layer and anterior stroma centrally; progress to deeper stroma sparing the periphery
163
Thiel-Behnke corneal dystrophy complications
RCE
164
Thiel-Behnke corneal dystrophy management
- monitor (slit lamp exam, photos)
- topical lubrication (for prophylaxis of RCE)
- if significant decrease in vision, refer for keratoplasty
- treat RCE
165
lattice dystrophy
amyloid deposits accumulate between the epithelial basement membrane and Bowman's layer as well as in stroma; stain with Congo red stain
166
lattice dystrophy etiology
genetic abnormality
167
lattice dystrophy demographics
typically becomes apparent in 1st decade
168
lattice dystrophy laterality
bilateral
169
lattice dystrophy symptoms
- asymptomatic
| - blurred vision
170
lattice dystrophy signs
- refractile white dots that coalesce into linear opacities; described as "glass like" (broken glass appearance); initially in anterior stroma centrally; progress to deeper stroma sparing the periphery
- intervening stroma becomes cloudy
171
lattice dystrophy complications
RCE
172
lattice dystrophy management
- monitor (slit lamp exam, photos)
- topical lubrication (for prophylaxis of RCE)
- if significant decrease in vision, refer for keratoplasty
- treat RCE
173
granular corneal dystrophy, type 1
hyaline-like deposits accumulate between the epithelial basement membrane and Bowman's layer as well as in stroma; stain red with Masson's trichrome stain
174
granular corneal dystrophy, type 1 etiology
genetic abnormality
175
granular corneal dystrophy, type 1 demographics
typically becomes apparent in 1st decade
176
granular corneal dystrophy, type 1 laterality
bilateral
177
granular corneal dystrophy, type 1 symptoms
- asymptomatic
| - blurred vision
178
granular corneal dystrophy, type 1 signs
discrete gray-white crumb-like opacities separated by clear stroma; resemble sugar granules or bread crumbs; initially in anterior to mid stroma centrally; progress to deeper stroma sparing the periphery
179
granular corneal dystrophy, type 1 complications
RCE
180
granular corneal dystrophy, type 1 management
- monitor (slit lamp exam, photos)
- topical lubrication (for prophylaxis of RCE)
- if significant decrease in vision, refer for keratoplasty
- treat RCE
181
granular corneal dystrophy, type 2 (Avellino dystrophy, combined granular-lattice dystrophy)
hyaline-like and amyloid deposits accumulate between the epithelial basement membrane and Bowman's layer as well as in stroma; stain red with Masson's trichrome and Congo red stains
182
granular corneal dystrophy, type 2 (Avellino dystrophy, combined granular-lattice dystrophy) etiology
genetic abnormality
183
granular corneal dystrophy, type 2 (Avellino dystrophy, combined granular-lattice dystrophy) demographics
typically becomes apparent during teenage years
184
granular corneal dystrophy, type 2 (Avellino dystrophy, combined granular-lattice dystrophy) laterality
bilateral
185
granular corneal dystrophy, type 2 (Avellino dystrophy, combined granular-lattice dystrophy) symptoms
- asymptomatic
| - blurred vision
186
granular corneal dystrophy, type 2 (Avellino dystrophy, combined granular-lattice dystrophy) signs
discrete gray-white crumb-like opacities separated by clear stroma combined with deeper linear opacities (sugar granules and broken glass)
187
granular corneal dystrophy, type 2 (Avellino dystrophy, combined granular-lattice dystrophy) complications
RCE
188
granular corneal dystrophy, type 2 (Avellino dystrophy, combined granular-lattice dystrophy) management
- monitor (slit lamp exam, photos)
- topical lubrication (for prophylaxis of RCE)
- if significant decrease in vision, refer for keratoplasty
- treat RCE
189
macular corneal dystrophy
GAGs accumulate within epithelium, Bowman's layer, stroma, Descemet's, endothelium; stain blue with Alcian blue
190
macular corneal dystrophy etiology
genetic abnormality
191
macular corneal dystrophy demographics
typically becomes apparent during 1st decade
192
macular corneal dystrophy laterality
bilateral
193
macular corneal dystrophy symptoms
blurred vision
194
macular corneal dystrophy signs
gray-white crumb-like opacities with stromal haze between deposits; initially in anterior stroma centrally; progress to deeper stroma extending limbus to limbus
195
macular corneal dystrophy complications
RCE
196
macular corneal dystrophy management
- monitor (slit lamp exam, photos)
- topical lubrication (for prophylaxis of RCE)
- if significant decrease in vision, refer for keratoplasty
- treat RCE
197
Schnyder corneal dystrophy
phospholipids and cholesterol accumulate within basal epithelial cells, Bowman's layer, and stroma; stain with Oil-Red-O and Sudan Black stains
198
Schnyder corneal dystrophy etiology
genetic abnormality
199
Schnyder corneal dystrophy demographics
typically becomes apparent during teenage years to 20s
200
Schnyder corneal dystrophy laterality
bilateral
201
Schnyder corneal dystrophy symptsom
blurred vision
202
Schnyder corneal dystrophy signs
- ring or disc-like central opacities with or without crystalline opacities; initially in anterior stroma centrally; progress to deeper stroma sparing the periphery
- prominent arcus senilis; progresses centrally leading to a diffuse haze
203
Schnyder corneal dystrophy management
- monitor (slit lamp exam, photos)
- topical lubrication (for prophylaxis of RCE)
- if significant decrease in vision, refer for keratoplasty or superficial keratectomy
- order lipid profile (has been linked with hypercholesterolemia and hyperlipidemia in some patients)
204
congenital hereditary endothelial dystrophy
congenital focal or diffuse thickening of Descemet's membrane endothelial degeneration
205
congenital hereditary endothelial dystrophy etiology
genetic abnormality
206
congenital hereditary endothelial dystrophy demographics
present at birth
207
congenital hereditary endothelial dystrophy laterality
bilateral
208
congenital hereditary endothelial dystrophy symptoms
blurred vision
209
congenital hereditary endothelial dystrophy signs
stromal edema
210
congenital hereditary endothelial dystrophy management
- monitor (slit lamp exam, photos)
| - if decreased vision, refer for keratoplasty
211
Thygeson's superficial punctate keratitis
opacities within the corneal epithelium (unknown composition)
212
Thygeson's superficial punctate keratitis etiology
idiopathic
213
Thygeson's superficial punctate keratitis demographics
typically presents between the ages of 20-30
214
Thygeson's superficial punctate keratitis laterality
bilateral
215
Thygeson's superficial punctate keratitis symptoms
- ocular irritation
- photophobia with tearing
- mild decreased vision
216
Thygeson's superficial punctate keratitis signs
- multiple small, gray-white corneal epithelial opacities; often central; slightly elevated; stain lightly with fluorescein
- minimal to no conjunctival injection, corneal edema, or AC rxn
217
Thygeson's superficial punctate keratitis management
- self-limiting within 1-2 months (typically resolves completely with no scarring)
- aggressive topical lubrication for mild symptoms
- topical steroid for moderate to severe symptoms
- Restasis, Xiidra, or tacrolimus may be an alternative or adjunctive treatment to a steroid
- BCL for comfort
218
Thygeson's superficial punctate keratitis pearls:
| -chronic course of exacerbations and remissions over the course of _____
10-20 years
219
band keratopathy
linear band of calcium that deposits at the level of Bowman's layer and anterior stroma
220
band keratopathy etiology/associations
- unknown etiology
- most commonly develops following chronic ocular disease (e.g., uveitis, corneal edema, dry eye, exposure keratopathy, glaucoma, phtisis bulbi), trauma, and ocular surgery (esp. retinal detachment repair with silicone oil)
- less commonly associated with hypercalcemia, hyperphosphatemia, gout, corneal dystrophy, myotonic dystrophy, long-term exposure to irritants (e.g., mercury fumes)
- may be congenital
221
band keratopathy demographics
depends on etiology
222
band keratopathy laterality
unilateral or bilateral
223
band keratopathy symptoms
- asymptomatic
- grittiness/FBS
- decreased vision
- corneal whitening
224
band keratopathy signs
white linear plaque of calcium at the level of Bowman's layer and anterior stroma; commonly has a swiss cheese appearance; typically within the interpalpebral fissure; separated from the limbus by a clear zone
225
band keratopathy management
- treat the underlying condition
- mild symptoms (i.e., FBS): aggressive topical lubrication, BCL for comfort
- moderate to severe (i.e., irritation not relieved by lubricants, obstructing vision): refer for chelation using disodium ethylenediamine tetraacetic acid (EDTA)
226
Salzmann's nodular degeneration
superficial corneal nodules composed of hyaline deposition between corneal epithelium and Bowman's layer or beyond into stroma
227
Salzmann's nodular degeneration etiology/associations
- unknown etiology
- most commonly develops following chronic ocular surface disease (e.g., MGD, pterygium, dry eye, exposure keratopathy, prior corneal surgery)
- may also be idiopathic
228
Salzmann's nodular degeneration demographics
- typically occurs between ages of 45-65
| - women > men
229
Salzmann's nodular degeneration symptoms
- asymptomatic
- FBS
- blurred vision
230
Salzmann's nodular degeneration signs
- elevated, smooth gray or blue-gray nodules anterior to Bowman's layer; may extend into stroma; usually midperipheral; single or multiple; base may be surrounded by epithelial iron deposits
- irregular astigmatism
231
Salzmann's nodular degeneration complications
RCE
232
Salzmann's nodular degeneration management
- treat the underlying condition
- correct the refractive error; topography can show associated astigmatism within the visual axis
- if significant discomfort or reduced vision due to progressive increase in astigmatic error, refer for superficial keratectomy or keratoplasty
233
exposure keratopathy
corneal drying due to prolonged exposure
234
exposure keratopathy etiology
- lagophthalmos (incomplete eyelid closure)
| - incomplete blink
235
exposure keratopathy demographics
no predilection
236
exposure keratopathy laterality
unilateral or bilateral
237
exposure keratopathy symptoms
- ocular redness
- ocular irritation (e.g., burning, FBS, pain)
- tearing
- blurred vision
238
exposure keratopathy signs
- inadequate blinking or closure of the eyelids
- conjunctival injection
- conjunctival staining with Lissamine green and Rose bengal; inferior 1/3 or in the interpalpebral region
- superficial punctate keratitis (SPK); inferior 1/3 or as a horizontal band in the interpalpebral region
- corneal epithelial breakdown; typically inferior
- corneal stromal melt; typically inferior
239
exposure keratopathy management
- treat the underlying condition
- aggressive topical lubrication
- eyelid taping or patching qhs in addition to topical lubrication
- punctal plugs in addition to topical lubrication
- BCL or scleral contact lens
- topical antibiotic for epithelial defects
- amniotic membrane in addition to topical antibiotic for non-healing corneal epithelial defects
- if significant stromal thinning occurs, limit the risk of corneal perforation by treating with ascorbic acid (promotes collagen synthesis) and citric acid or a tetracycline (inhibits collagenolysis); also discuss eye protection
- if medical therapy fails, refer for surgery
240
exposure keratopathy complications
- microbial keratitis
| - corneal perforation
241
exposure keratopathy pearls:
- damage to CN V can _____
- CN V plays an important role in _____
- causes of CN V damage include _____
exacerbate any corneal issue (neurotrophic keratopathy);
wound healing, the blink reflex, and tear production and secretion;
HSV and HZO keratitis, CL wear, refractive surgery, keratoplasty, diabetic neuropathy, chemical injury stroke
242
iridocorneal endothelial syndrome (ICE syndrome)
represents a spectrum of 3 diseases linked by a fundamental defect of corneal endothelium and variable iris abnormalities:
- progressive iris atrophy (essential iris atrophy)
- Chandler's syndrome
- Cogan-Reese syndrome (iris nevus syndrome)
243
iridocorneal endothelial syndrome (ICE syndrome) etiology
unknown etiology
244
iridocorneal endothelial syndrome (ICE syndrome) demographics
- typically occurs between the ages of 20-50
| - women > men
245
iridocorneal endothelial syndrome (ICE syndrome) laterality
unilateral
246
iridocorneal endothelial syndrome (ICE syndrome) symptoms
- asymptomatic
- blurred vision, worse in the morning
- may note an irregular pupil or iris appearance
- monocular diplopia
247
iridocorneal endothelial syndrome (ICE syndrome) signs
- corneal endothelial changes (loss of endothelial mosaic similar to Fuch's dystrophy); fine, beaten metal appearance
- variable corneal edema; more severe in Chandler syndrome
- iris abnormalities; progressive iris atrophy: marked iris thinning leading to iris atrophy, holes and corectopia (displacement of the pupil); Chandler's syndrome: mild iris thinning and corectopia; Cogan-Reese syndrome: fine, pigmented nodules on the iris surface, ectropio uveae, and variable iris atrophy
248
iridocorneal endothelial syndrome (ICE syndrome) management
- to treat corneal edema: hypertonic saline, use of hairdryer in morning
- if severe endothelial dysfunction and cornea edema does not clear, refer for keratoplasty
- if glaucoma develops, treatment is similar to POAG; IOP lowering drops may improve corneal edema
249
iridocorneal endothelial syndrome (ICE syndrome) complications
- secondary open angle glaucoma; corneal endothelial cells may migrate over the TM and impair aqueous outflow
- secondary closed angle glaucoma; corneal endothelial cells may migrate over the anterior iris and form peripheral anterior synechiae (which then contract and close the angle)
250
iridocorneal endothelial syndrome (ICE syndrome) pearls:
- _____ is the most common variant (50% of ICE syndrome cases)
- a _____ disease, but in some cases, subclinical abnormalities of the corneal endothelium may be seen _____
Chandler syndrome;
unilateral;
in the asymptomatic fellow eye
