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Flashcards in Corneal Dystrophies Kwan Deck (56)
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1

key characteristics of corneal DEGENERATIONS

-peripheral cornea affected more often
-local and systemic diseases associated
-occurs sporadically, can occur in presence of inflammation and neo
-can be unilateral but often bilateral
-progression varies, but can be rapid

2

list of some age-related corneal degenerations

-arcus
-Vogt's limbal girdle
-crocodile shagreen
-hassall-henle bodies
-corneal farinata
-polymorphic amyloid degeneration

3

list of some NON age-related corneal degenerations

-band keratopathy
-terrien marginal degeneration
-spheroidal degeneration
-salzmann nodular degeneration
-pellucid marginal degeneration
-pigmentary iron lines
-coats white ring
-lipid keratopathy
-corneal deposits

4

what is an Arcus caused by

depositions of lipid in the peripheral corneal stroma

5

where are lipid deposits first seen in Arcus? (what layers)

near Descemet's membrane and later near Bowman's

6

what sectoral pattern does the Arcus usually follow? (which area affected first)

-inferior
-superior
-nasal
-temporal
(complete ring)

7

where is the clear zone in an Arcus?

between limbus and lipid deposition

8

what is "furrow degeneration" in Arcus?

thinning that occurs in clear zone

9

what are some trends for ages/races/sex affected by Arcus

-100% of men over 80
-women later
-african americans earlier

10

what if you have a a patient under 40 with arcus

-indication for laboratory testing
-suspect hypercholestereia, lipid abnormalities

11

what if you have a patient with unilateral arcus?

-eye without arcus is the side where carotid artery disease may be more severe

12

condition that is a bilateral yellow-white band at the nasal and temporal limbus of the peripheral cornea and incidence increases with age

Vogt's limbal girdle

13

which type of Vogt's Limbal Girdle:
-well demarcated white band that may have holes
-clear area adjacent to limbus
-early calcific band keratopathy

Type 1

14

which type of Vogt's Limbal Girdle:
-solid chalky white band without holes or clear zone
-may extend centrally in an irregular linear fashion

Type 2

15

describe the appearance of the age related Crocodile Shagreen

-cobblestone or crocodile-skin appearance in the anterior or posterior cornea
-polygonal gray to white opacities form and are separated by lucent lines

16

condition containing sub epithelial calcium deposits in Bowman's layer that is associated with chronic ocular inflammatory disease (such as uveitis, interstitial keratitis, hypercalcemic states, secondary to topical medication use)

Band Keratopathy

17

what is the appearance and pattern of band keratopathy

-starts as gray-white nasal temporal interpalpebral opacity that advances centrally
-looks like swiss cheese holes in the band

18

condition that is a slowly progressive peripheral corneal inflammatory and degenerative disorder with overlying superficial vascularization and characterized by ATR astigmatism

Terrien Marginal Degeneration

19

what is the patient demographic that gets Terrien Marginal Degeneration (age, sex)

-men more affected than women 3:1
-most offen occurs age 20-40

20

where does Terrien Marginal Degeneration start and what is its appearance

generally starts in the supra nasal peripheral cornea with small white opacities in anterior stroma

21

rare condition that can occur on the cornea, conj, or both and is from UV exposure, aging, environmental, trauma

spheroidal degeneration

22

how does spheroidal degeneration begin and what does it look like as it progresses

-begins with interpalpebral small clear droplets under the epithelium at 3/9 o'clock
-spherules enlarge, become gold or brown, progress centrally
-can coalesce into larger droplets and become elevated

23

what degeneration is characterized by single or multiple white, gray-white, or bluish elevated lesions in the central or peripheral cornea adjacent to an area of corneal scarring, vascularization, edema, or even normal cornea

Salzmann Nodular Degeneration

24

what patients get Salzmann Nodular Degeneration

-occurs in eyes that have or have had chronic inflammation
-increases with age and higher in women

25

signs and symptoms of Salzmann Nodular Degeneration

-foreign body sensation
-erosions of the epithelium can occur with notably elevated nodules

26

corneal thinning and ectatic condition characterized by a crescent shaped band of thinning inferior cornea from 4 to 8 o'clock and high ATR astigmatism

Pellucid Marginal Degeneration

27

describe the thinning that occurs in Pellucid Marginal Degeneration

-crescent shaped band of thinning inferior cornea from 4 to 8 o'clock
-thinned area 1-2mm wide and clear
-corneal stromal thinning and absence of Bowman's layer in affected area

28

what is the most common epithelial iron line and where is it located?

Hudson-Stalhi line in the lower one third of the cornea above eyelid margin

29

what are some key features of corneal DYSTROPHIES

-primary disorders (no systemic involvement)
-bilateral and symmetrical
-early onset, usually by 20s
-involvement of only one layer of the cornea
-central corneal location
-autosomal dominant inheritance (AD)

30

what are some epithelial, basement membrane, and Bowman's layer dystrophies

-epithelial basement membrane dystrophy (EBMD)
-meesmann epithelial dystrophy
-reis-bucklers dystrophy
-stocker-holt, lisch, grayson-willbrandt
-genetic disease

31

other names for epithelial basement membrane dystrophy (EBMD)

-map-dot fingerprint
-cogan's microcystic
-anterior basement membrane

32

signs and symptoms of epithelial basement membrane dystrophy (EBMD)

-bilateral
-age of onset usually 20-40
-about 10% develop painful recurrent epithelial erosions (RCE)
-otherwise asymptomatic or slight blur

33

why does epithelial basement membrane dystrophy (EBMD) occur?

-abnormal turnover, maturation, and synthesis of the corneal basement membrane
-blocks normal migration of epithelial cells towards the surface

34

in epithelial basement membrane dystrophy (EBMD), what are the maps and fingerprint lines due to

thickening of the basement membrane

35

epithelial basement membrane dystrophy (EBMD), what produces the dot appearance

microcysts (trapped cellular debris)

36

what corneal dystrophy is characterized by a myriad of fine, round, intraepithelial cysts of uniform size and shape, interpalpebral zone

Meesmann's Dystrophy

37

what is the age of onset and pattern of progression for Meesmann's Dystrophy

-visible by 12 months of age, increase in number throughout life
-asymptomatic until adolescence
-bilateral, symmetric
-minority may experience rupture of corneal micro cysts

38

what is the dystrophy of Bowman's layer causing thickened epithelium, irregular astigmatic, RCE that occurs in early childhood

Reis-Bucklers Dystrophy

39

what are some signs and symptoms of Reis-Bucklers Dystrophy

-bilateral, symmetrical
-RCE, photophobia, foreign body sensation, irritation, pain
-anterior stromal haze compromises vision in 2nd and 3rd decades
-honeycomb or fishnet shaped opacities within the central cornea, Bowman's and anterior stroma

40

what is the most common stromal dystrophy

granular dystrophy

41

stromal dystrophy from deposition of branching figures containing amyloid and develops in teenage years

lattice dystrophy

42

signs and symptoms of lattice dystrophy

-thin, centrally located branches associated with sub epithelial opacities and anterior stream haze
-can have painful bilateral RCE
-often requires penetrating keratoplasty in third or fourth decade of life (5% recurrence rate in corneal graft)

43

stromal dystrophy characterized by grayish white round opacities in the anterior central stroma from hyaline deposition that onsets in the 1st decade

granular dystrophy

44

signs and symptoms of granular dystrophy

-breadcrumb, snowflake, popcorn looking opacities
-onset in 1st decade but few visual disturbances until 5th decade (after opacities increased in number and size and coalesced)
-photophobia from deposits scattering light
(but RCE episodes are rare)

45

what stromal dystrophy is autosomal recessive, onsets in first decade, is characterized by progressive visual impairment, and is from MPS accumulation?

macular dystrophy

46

signs and symptoms of macular dystrophy

-RCE, attacks of severe irritation and photophobia
-diffuse superficial clouding in central cornea (can extend peripheral)
-gray-white opacities with indistinct borders, ground glass haze
-descemet's membrane and endothelium affected (but epithelium spared)

47

minimum amount of endothelial cells you need

1000-1200 cell/mm^2 (density)

48

what % of endothelial cell loss can you get with intraocular surgery

0-30%

49

what is normal attrition of endothelial cells/year

central cornea loses 100 to 500 cells per year

50

signs and symptoms of Fuchs

-progressive, guttatae, thickening of Descemet's membrane
-loss of endothelial cell density, stream edema
-blur predominately in the morning
-age of onset 40-60
-women affected more 3:1
-epithelial bull, bullous keratopathy

51

what genetic testing is a 96% positive predictive value for Fuchs

repeating trinucleotide (TGC in the TCF4 gene)

52

what are some key features of the rare congenital hereditary endothelial dystrophy (CHED)

bilateral diffuse corneal clouding, hazy to milky
-progression over 1-10 years
-no recurrence in grafted cornea

53

which type of congenital hereditary endothelial dystrophy (CHED) has:
-onset delayed until first year(s) of life
-photophobia, tearing
-hearing deficient, slowly progressive

CHED 1
(autosomal dominant, more common)

54

which type of congenital hereditary endothelial dystrophy (CHED) has:
-diagnosed at or shortly after birth (within 1 year)
-nystagmus, ambylopia
-severe edema - corneal thickness 2-3x the normal values

CHED 2
(autosomal recessive, more severe)

55

what dystrophy is characterized by edematous clouding and secondary sub epithelial band-shaped keratopathy that is slow to non progressive, asymmetric course

posterior polymorphous dystrophy (PPMD)

56

signs/ symptoms of posterior polymorphous dystrophy (PPMD)

-isolated, confluent or clustered vesicular and blister like lesions as well as "railroad tracks"
-secondary glaucoma secondary to trabecular invasion