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102 Cards in this Set
- Front
- Back
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How are corneal dystrophies classified? |
Based on anatomy: 1. Epi and subepi dystrophy 2. Epi-stromal dystrophy 3. Stromal dystrophy 4. Endo dystrophy |
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What is a corneal dystrophy? |
An inherited disorder than affects a single or combination of cells, tissues and/or organs. Usually bilateral, symmetric, slowly progressive and not related to environmental or systemic factors. However there are exceptions to this. |
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EBMD and central cloudy dystrophy of Francois are inherited disorders in the majority of patients. T/F? |
False, they are degenerative rather than hereditary in the majority of cases |
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What are some epithelial and subepithelial dystrophies? |
EBMD = majority degenerative Epithelial recurrent erosion dystrophies (EREDs) - Franceschetti dystrophy, dystrophia smolandiensis, dystrophia helsinglandica Subepithelial mucinous corneal dystrophy Meesman corneal dystrophy Lisch epithelial corneal dystrophy Gelatinous drop-like corneal dystrophy |
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What are some epithelial-stromal TGFBI dystrophies? |
Reis-Bucklers (RBCD) Thiel-Behnke (TBCD) Lattice (LCD, types 1-4) Granular type 1 (GCD1) Granular type 2 (GCD2) |
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What are some stromal dystrophies? |
Macular (MCD) Schnyder (SCD) Congenital stromal (CSCD) Fleck (FCD) Posterior amorphous (PACD) Central cloudy dystrophy of Francois (CCDF) Pre-Descemet (PDCD) |
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What are some endothelial dystrophies? |
Fuchs endothelial (FECD) Posterior polymorphous (PPCD) Congenital hereditary endothelial (CHED) X-linked endothelial (XECD) |
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What are the characteristics of EBMD and it's alternate names? |
Map-dot-fingerprint dystrophy, cogan microcystic epithelial dystrophy, anterior basement membrane dystrophy Rarely category 1 dystrophy It's mostly degenerative of secondary to trauma. Affects gene locus 5q31 Onsets mainly in adults Signs: poor adhesion of epi cells to weird BM laminar material causing recurrent erosions |
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What are maps in EBMD |
Irregular patches of thick, grey, hazy epi with scalloped borders Mostly central and paracentral cornea Sheets of intraepithelial, multilaminar basal laminar material, 2-6nm thick |
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What are dots in EBMD |
Typical of Cogan's microcystic type EBMD Irregular round/oval/comma shaped Nonstaining Grey intraepi opacitis Clustered in central cornea Intraepi pseudocysts containing cytoplasmic debris, degenerating cells |
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What are fingerprint lines in EBMD? |
Parallel, curvilinear lines Usually paracentral Intraepi extensions of basal laminar material Fibrillar substance = 17nm diam Granular substance = 8nm diam |
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What are blebs in EBMD? |
Subepi pattern like patterned glass Irregular subepi accumulation of fibrillogranular material, deposited between epithelium and Bowman's layer |
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What are symptoms of EBMD |
Asymptomatic with painful erosive episodes May cause reduced vision by inducing astig (monocular diplopia, ghosting) |
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EBMD presentations A = maps B = dots C = fingerprints D = blebs |
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What are the characteristics of EREDs? |
Variants: Franceschetti CD, Dystrophia Smolandiensis, Dystrophia Helsinglandica Category 3 Inheritance is AD, and affected genes unknown Onsets in early childhood Signs: recurrent epi erosions in first decades of life lastin 1-7d. In pain free periods, no changes are present. Mid-life: diffuse, central subepi opacity, subepi fibrosis, or protruding keloid-like formations develop |
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What are the symptoms of EREDs? |
Severe, painful attacks start at night Visual impairment from central corneal opacification after erosions in 50% of cases With advancing age there is a reduction in frequency of painful erosive episodes Slow progression of central opacity impairs VA |
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What is the pathophysiology of FRCD? |
Irregular basal epi size and shape with enlarged intracellular spaces Partial destruction and absence of Bowman's layer with connective tissue pannus between basal epi and Bowman's layer |
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What is the pathophysiology of DS? |
Keloid-like structure indicating amyloidosis Fibronectin present in central subepi stroma, localised in areas with subepi fibrosis Immunoreactive keratocytes also in those areas Abnormal thinning of epi, absence of Bowman layer with accumulation of pathological material. Subepi corneal nerves are sparse and tortuous |
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What are the characteristics of SMCD? |
AD inheritance mainly, also possibly X-linked Affected genes unknown Category 4 Onset first decade of lie Signs: diffuse bilateral subepithelial opacitis and haze most dense centrally |
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Symptoms of SMCD? |
Painful episodes of recurrent corneal erosions, decreases in freq during adolescence The course is progressive vision loss in adolescence |
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Pathophysiology of SMCD? |
Subepi depositio of eosinophilic plus other stuff like fibrillar material present anterior to Bowman's layer |
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FRCD A = early life with normal looking cornea B = diffuse central haze of epi/subepi layer in advanced age |
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SMCD Diffuse subepi opacities and haze centrally |
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Describe the characteristics of Meesmann CD? |
Alternately = juvenile hereditary epithelial dystrophy Category 1 Inheritance = AD Gene loci = 12q13, 17q12 Onset = early childhood Signs = multiple tiny intraepi vesicles extend to limbus, most numerous in intrapalpebral area, diffuse grey opacities, with many different patterns, 85% of eyes have grey microcysts affectin entire epi while other are more localised |
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Symptoms of MCD? |
Asymptomatic May have mild reduced vision Some have glare, light sensitivity FB sensation and tearing may be from recurrent epi erosions Rarely blur from corneal irregularity and scarring Course is stationary or slowly progressive |
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Pathophysiology of MCD? |
Thick, disorganised epi, intraepi cysts filled with fribrogranular material and cytoplasmic filaments, vacuolated and degenerating cells Variably thickened BM projecting into epi, Bowman layer and stroma are normal |
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MCD A = diffuse grey superior opacity B = same eye, transparent microcysts |
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Describe the characteristics of LECD? |
Alternately = band shaped and whorled microcystic dystrophy of the corneal epi Category 2 Inheritance = X chromosomal dominant Gene locus = Xp22.3 Onset = childhood Signs= localised grey opacities in different patterns: whorled, radial, band, flame, feathery, club shaped. These are clear cysts. Minimal or asymmetric. |
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Symptoms of LEC? |
Asymptomatic of blurred vision if pupillary axis involved Course is slow progression with possible visual deterioration |
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Pathophysiology of LECD? |
Epi basal cells are cuboidal, in suprabasal and parabasal layers, vacuolated cells progress to epi surface where they become squamous shaped |
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LECD A and B = diffuse grey opacities in radial, feathery or club shaped pattern |
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LECD Whorled pattern |
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What are the characteristics of GDLD? |
Alternately = subepithelial amyloidosis, primary familial amyloidosis Category 1 Inheritance = AR Gene locus = 1p32, gene = TACSTD2 Onset = 1st-2nd decade Signs = intitially subepi patterns in band shapes, or may be grouped nodules, stain with fluoroscein indicating epi hyperpermeability. Superficial vascularisation is often seen Later life = stromal opacification or larger nodules, kumquat-like lesions |
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Symptoms of GDLD? |
Significant reduced vision, photophobia, irritation, redness, tearing Course = progress to protruding subepi deposits and stromal opacity. Recurrences after corneal surgery within a few years |
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Pathophysiology of GDLD? |
Subepi and stromal amyloid deposits Disrupted epi tight jts superficially Amyloid in basal epi layer Mildly disorganised epi structure and irregular cell shape |
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What are the characteristics of Reis-Buckler CD? |
Alternately = CD of Bowman layer type 1, geographic CD, atypical granular CD, granular CD, etc. Category 1 Inheritance = AD Gene locus = 5q31, gene = TGFBI Onset = childhood Signs = confluent early irregular geographic opacity, varying density in Bowman layer and superficial stroma. Initially discrete and subsequently extending into limbus and deeper stroma |
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Symptoms of RBCD? |
Impaired vision from childhood Painfull recurrent erosions Course = slowly progressive deterioration of vision. RCE reduce with time. Similar to TBCD but more aggressive |
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Pathophysiology of RBCD? |
Bowman layer replaced with sheet layer of granular deposits which can extend into the stroma and sparse round deposits appear in middle and posterior stroma |
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GDLD A - band shaped keratopathy B = mulberry shaped C = fluoroscein showing hyperpermeability of epi D = kumquat like diffuse stromal opacity |
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RBCD A = geographic opacity B = geographic opacity extending to limbus |
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What are the characteristics of TBCD? |
Alternately = honeycomb shaped CD, Waardenburg-Jonkers CD category 1 Inheritance = AD Gene loci = 5q31, gene = TGFBI Onset = early childhood Signs = initially solitary flecks or irregularly shaped opacities at the level of Bowman layer, followed by symmetrical subepi honeycomb opacities Peripheral corneal typically uninvolved In older pts - progresses to deeper stromal layers and corneal periphery |
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Symptoms of TBCD? |
RCE cause pain in first and second decades Gradual vision impairment Erosions reduce in freq, onset of vision impairment are later than in RBCD Course = slow progression due to corneal scarring, RCE reduce with time, less aggressive than RBCD |
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Pathophysiology of TBCD? |
Irregular thick and thinning of epi layer to compensate ridges and furrows in stroma, focal absence of epi BM Bowman layer replaced by superficial fibrocellular pannus with wavy sawtooth pattern, curly collagen fibres distinguished TBCD from RBCD Deposits in epi and Bowman layer |
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What are the characteristics of LCD1 and variants |
Alternately = Biber-Haab-Dimmer Category 1 Inheritance = AD Gene locus = 5q31, gene = TGFBI Onset = 1-2 decade Signs = first signs are supericial fleck opacities at end of first decade, lattice lines visible in deeper layers (superficial stroma) Thin branching refractile lines and/or subepi whitish ovoid dots at end of first decade Start central and superificial, spread centrifugally and deep Progresses to: diffuse subepi ground glass haze in central and paracentral cornea with lattice lines and recurrent erosions Variant LCDIIIA shows thicker lattices lines, LCDIV has deeper deposits without epi erosion |
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Symptoms of LCD1? |
Ocular discomfort, visual impairment, as early as first decade Course = progressive, marked vision reduction by fourth decade |
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Pathophysiology of LCD? |
Epi atrophy, disruption and degeneration of basal epi cells, focal thinning/absence of Bowman's, progresses with age Eosinophilic amyloid material accumulates between epi BM and bowman's Stromal deposition of amyloid distorts structure of lamellae Descemet membrane and endo are normal |
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LCD1 A = direct illumination B = retro C = subepi groud glass haze of central and inferior cornea, diffuse lattice lines D = dots and paracentral lattice lines |
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LCD variants A = type 3a, ropey thick lattice lines extending to limbus B = type 4 = mimimal, centra fleck opacities in deep cornea, few lattice lines, erosions absent |
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What are the characteristics of GCD1 |
Inheritance = AD Category 1 Gene locus = 5q31, gene = TGFBI Onset = childhood as early as 2yo Signs = in kids, vortex pattern of brown granules superficial to Bowman layer As they age, well defined white granules with intervening stroma, size and number of granules increases causing snoflake appearance Retro illum makes them look glassy and transluscent, crushed bread crumb like Do not extend to limbus Extend into deeper stroma, approach Descemet's |
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Symptoms of GCD1? |
Glare and photophobia in early disease VA decreases with age RCE seen frequently Course = progresses, opacities become confluent in superficial cornea and reduce VA |
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Pathophysiology of GCD1? |
Multiple stromal deposits from deep epi to Descemet membrane Hyaline opacities |
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GCD1 A = in kids, early subepi opacities B = stromal deposits C+D = adult, more prominent, diffuse, snowflake like opacities |
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What are the characteristics of GCD2? |
Alternately = Avellino CD Category 1 Inheritance = AD Gene locus = 5q31, gene = TGFBI Onset = homozygous at 3yo, heterzygous at 8yo, most diagnosed during teens Signs = subtle superficial stromal tiny white dots, devleop into spokes or thorns. Later, superficial white round patches that have moth eaten centres, appear discoid. Spiky anterior to midstromal deposits develop in star, icicle or spider shape. Could have translucent dash or dot deposits in posterior stroma RCE cause dropout of superficial granules and thickening of cornea, and translucent breadcrumb opacities coalesce in sub-Bowman anterior stroma |
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How to differentiate between LCD and GCD2? |
Dashes/dots in GCD2 can be distinguished from lattice lines in classic LCD 1. dashes appear whiter and lattice lines in LCD are more refractile 2. dashes rarely cross each other, lattice lines in LCD intersect |
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Symptoms of GCD2? |
VA decreases with age, pain accompanies epi erosions Course = slow progression |
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Pathophysiology of GCD2? |
Amyloid and hyalin deposition in anterior stroma |
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GCD2 A = 13yo with few white dots B = older adult with spokes/thorns C = breadcrumb opacity beneath Bowman's, dense icicles and disc opacities D = homozygote with more severe, confluent opacities |
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What are the characteristics of MCD? |
Alternately = Fehr speckled dystrophy Category 1 Inheritance = AR Gene locus = 16q22, gene = CHST6 Onset = childhood Signs = initial central and superficial irregular white flecks, involve limbus and deep stroma down to Descemet's. Progressive haze develops involving entire corneal stroma, epi remains smooth but occasionally erodes Cornea much thinner than normal As disease progresses, Descemet's becomes grayer, develops guttata |
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Symptoms of MCD? |
Severe vision impairment between 10-30yo Corneal sensitivity reduced Photophobia and painful RCE can occur rarely Course = slowly progressive |
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Pathophysiology of MCD? |
Breaks in Bowman's layer GAGs accumulate intra and extracellularly in stroma |
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MCD A = flecks in early stage B = spreading to limbus and deep stroma C = diffuse opacities involving entire stroma |
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What are the characteristics of SCD? |
Many alternate names, used to be called crystalline dystrophy, but this only occurs in 50% Category 1 Inheritance = AD Onset = may be in childhood but diagnosis normally in second/third decade Signs = Pts 23yo or younger have disc like central corneal opacity +/- central comma shaped subepi crystals 23-38yo = arcus lipoides also noted After 38yo = midperipheral panstromal haze, entire cornea appears hazy |
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Symptoms of SCD? |
VA decreases, glare increases with age Scotopic vision good, photopic vision decreased Corneal sensitivity reduces with age Course = slowly progressive, severe reduction of photopic vision |
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Pathophysiology of SCD? |
Abnormal deposition of intra and extracellular phospholipids and cholesterol in basal epi cells, Bowman layer, stroma Secondary amyloid deposition |
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SCD A = central stromal opacity in early SCD B = early crystalline deposits C = central opacity with arcus lipiodes D = central corneal opacity, subepi crystalline ring, midperipheral haze, arcus lipoides E = Non-crystalline diffuse central opacity with midperipheral haze and arcus F = non-crystalline, central opacity, midpeipheral haze, prominent arcus |
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What are the characteristics of CSCD? |
Alternately = congenital hereditary stromal dystrophy Category 1 Inheritance = AD Onset = congenital Signs = diffuse, bilateral, central clouding, with white flake opacities in stroma. Changes are equal in all areas of cornea. Corneal surface is normal, with increased stromal thickness |
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Symptoms of CSCD? |
Moderate to severe visual loss Photophobia in minority Course = nonprogressive or slow progression |
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Pathophysiology of CSCD? |
Irregular stromal lamellae, contains accumulation of decorin Increased corneal thickness Epi cells are normal, endo is normal |
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CSCD Diffuse clouding with flake opacities |
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What are the characteristics of FCD? |
Category 1 Inheritance = AD Onset = congenital or first years of lie Signs = subtle, distinct small traslucent disc opacities or flat grey dandruff opacities through any level of otherwise clear stroma. May extend to limbus Epi, bowman's, Descemet, and endo are uninvolved Asymmetric unilateral corneal involvement is possible |
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Symptoms of FCD? |
Asymptomatic, may have slight photophobia or reduced corneal sensitivity Course = nonprogressive |
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Pathophysiology of FCD? |
Swollen, vacuolated keratocytes containing GAGs and lipids |
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FCD, fleck/dandruff opacities |
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What are the characteristics of PACD? |
Category 1 Inheritance = AD Onset = often in first decade and as early as 16wks Signs = diffuse grey white sheet opacity involving any layer of stroma Can be centroperipheral, extend to limbus, or peripheral with less pronounced findings Stromal breaks often present, decreased corneal thickness and flattening to <41D Descemet and endo may be indented by opacities Prominent schwalbe's line, fine iris processes, pupillary remnants, iridocorneal adhesions, corectopia, pseudopolycoria, anterior stromal tags have been reported |
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Symptoms of PACD? |
VA mildly affected, usually better than 6/12 Course = none or slowly progressive |
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Pathophysiology of PACD? |
Irregular posterior stromal lamellae, thin Descemet membrane, focal attenuation of endo cells |
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PACD A = central deep stromal opacity with peripheral extension B = thinned cornea with posterior stromal lamellar opacification |
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What are the characteristics of CCDF? |
Category 4 Inheritance = unknown, AD occasionally, may be a degeneration Onset = first decade Signs = cloudy central polygonal or rounded stromal opacities, fade anterioral and peripherally and are surrounded by clear tissue UNDISTINGUISHABLE FROM POSTERIOR CROCODILE SHAGREEN |
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Symptoms of CCDF? |
Mostly asymptomatic Course = nonprogressive |
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Pathophysiology of CCDF? |
Faint undulating appearance of deep stroma, extracellular vacuoles some contain fibrillogranular material. Endo vacuoles with fibrillogranular pattern have also been reported |
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CCDF or posterior crocodile shagreen Stromal opacities separated by linear areas of clear cornea |
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What are the characteristics of PDCD |
PDCD associated with X-linked ichthyosis = category 1 Isolated PDCD = category 4 Inheritance = Isolated is not well defined nor clearly hereditary. Other forms may be AD, X-linked, etc Onset = usually after 30yo, has been seen in 3yo Signs = several subgroups which are sporadic, age-related degenerative changes Focal, fine, polymorphic gray opacities that are central, aanular or diffuse in deep stroma Punctiform and polychromatic = changes are uniform and cornea is otherwise normal Associated with systemic diseases = KC, posterior polymorphous dystrophy, EBMD, CCDF |
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Symptoms of PDCD? |
mostly asymptomatic Couse = punctiform and polychromatic are nonprogressive, other forms show progression |
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Pathophysiology of PDCD? |
Normal cornea except enlarged keratocytes in posterior stroma containing vacuoles and intracytoplasmic inclusions of lipid like material |
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PDCD Punctate opacities anterior to Descemet membrane |
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What are the characteristics of FECD? |
Inheritance = mostly unknown, may be AD Onset = 4th decade or later, early variant starts in first decade Predominantly females! Signs = guttata start centrally and spread peripherally, some pts advance to endo decompensation and stormal edema Endo has beaten metal appearance with or without pigment dusting Descemet = thickened, stromal edema may progress to involve epi causing bullae and bullous keratopathy Subepi fibrosis, scarring, peripheral superficial vascularisation from chronic edema |
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Symptoms of FECD? |
Intermittent reduced vision VA worse in morning due to increased edema overnight pain, photophobia, epiphora due to erosions and bullae Progressive vision loss Couse = progressive |
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Pathophysiology of FECD? |
Diffuse, thickening of Descemet, sparse atrophic endo cells, gutta in Descemet's Degeneration, thinning and reduction of endo cells Early onset FECD = Severe disorganisation of stromal collagen lamellae |
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Category of FECD? |
1 = early onset FECD 2 = patients with identified genetic loci 3 = patients without known inheritance |
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FECD A = corneal guttata B+C = epi edema and bullae, endo decompensation and stromal edema |
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What are the characteristics of PPCD? |
Category 1 = PPCD2/3 Category 2 = PPCD 1 Inheritance = AD, isolated unilateral cases with no heredity Onset = early childhood Signs = often asymmetric. Opacities in Descemet and endo Geographic grey opacities, vesicular lesions, single or grouped, often surrounded by grey circular opacity parallel grey white endo bands Some cases have diffuse Descemet opacification and larger vesicular endo opacities Keratoconic and nonkeratoconic steepening are possible Corneal edema in 20-25% of pts Peripheral iridocorneal adhesions in 25%, elevated IOP in 15% |
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Symptoms of PPCD? |
Often asymptomatic, vision impairment may occur secondary to corneal edema Course = rarely congenital corneal clouding. Endo often unchanged for years. Possible slow progression of vesicles and greater thickness of Descemet over years and decades |
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Pathophysiology of PPCD? |
Multiple layers of collagen on posterior surface of Descemet, focal fusiform or nodular excrescence. Blebs, discontinuities or reduplication of endo cell layer, polymegethism Endo cell display epi cell characteristics; microvilli and desmosomes |
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PPCD A = endo plaque lesions B = craters on Descemet membrane C = railroad track alteration |
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What are the characteristics of CHED? |
Category 1 Category 3 = pts with SLC4A11 mutations Inheritance = AR Onset = congenital Signs = bilateral and often asymmetric Corneal clouding = diffuse haze to ground glass milk appearance with occasional focal grey sptos Thickining of cornea Rarely secondary band keratopathy Rarely elevated IOP Endo cell count reduced significantly |
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Symptoms of CHED? |
Blurred vision and nystagmus Minimal to no tearing or photophobia Course = little or no progression |
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Pathophysiology of CHED? |
Diffuse epi and stromal edema, defects in Bowman's, degenerated endo with multinucleated and atrophic endo cells, thickened laminated Descemet due to abnormal secretion by endo cells Severe disorganisation of stromal lamellae |
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CHED C = diffuse stromal thickening |
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What are the characteristics of XECD? |
Category 2 Inheritance = X linked onset = congenital Signs = Males: congenital clouding from diffuse haze to ground glass milk, possible nystagmus, moon crater endo changes, secondary band keratopathy Females: only moon crater endo changes |
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Symptoms of XECD? |
Males = blur Females = asymptomatic Course = males: little progression females: no progression |
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Pathophysiology of XECD? |
Moon crater endo changes, subepi keratopathy Irregular epi and Bowman layer thinning Irregular collagen lamellae in anterior stroma Irregular thickening of Descemet with small excavations and loss of endo cells with weird appearance |
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XECD A = male baby B = mother with moon crater endo changes |
