corneal dystrophies

Download Corneal  dystrophies

Post on 24-Feb-2016

212 views

Category:

Documents

0 download

Embed Size (px)

DESCRIPTION

Corneal dystrophies. Corneal dystrophies. Group of progressive , usually bilateral , mostly genetically determined , non inflammatory opacifying disorders Classification Epithelial Bowman layer Stromal Endothelial . Epithelial dystrophies. Cogan epithelial basement membrane dystrophy - PowerPoint PPT Presentation

TRANSCRIPT

Slide 1

Corneal dystrophiesCorneal dystrophiesGroup of progressive , usually bilateral , mostly genetically determined , non inflammatory opacifying disorders

Classification EpithelialBowman layerStromalEndothelial Based on biomicroscopical and histopathological features3Epithelial dystrophiesCogan epithelial basement membrane dystrophy

Meesman epithelial dystrophy

Lisch epithelial dystrophy4Epithelial dystrophiesCogan epithelial basement membrane dystrophyInheritance SporadicHistology Thick basement membraneDeposits of fibrillary proteinAbsence of hemidesmosomes

Most common dystrophy seen in practiceDeposits b/w basement memb and bowman layerHemi of basal epithelial cells responsible for recurrent corneal errosions5Epithelial dystrophiesCogan epithelial basement membrane dystrophyOnset Signs Dot like opacitiesEpithelial microcystSubepithelial map like patternWhorled fingerprint like lines

2nd dacade ----10% develop recurrent corneal errosions in 3rd decadeSigns may b seen in isolation or combinationOver time one pattern frequently changes to other ----distribution of the lesion also vary6Epithelial dystrophies2. Meesmann epithelial dystrophy

Inheritance Histology Basement membrane thickningIntraepithelial cystSymptoms AsymptomaticOcular irritation

AD

7Epithelial dystrophies2. Meesmann epithelial dystrophy

Signs Tiny intraepithelial cystsReduced sensationsSlightly thinned

Treatment

1-Of uniform size,maximal centrally and extends towrds but do not reach limbusTreatment not normally required other than lubricants8Epithelial dystrophies3. Lisch epithelial dystrophy

InheritanceAD or XLDGene locus on Xp 22.3 in XLD

Signs Grey band with whorlsDensely packed microcysts

On reteroillumination9Bowman layer dystrophies1. Reis Bucklers dystrophy ( CDB1, GCD type 3)

Inheritance ADGene locus 5q31

Histology Replacement with fibrous tissue

Onset 1st or 2nd decade

Corneal dystrophy of bowman layer type 1/ granular stromal dystrophy type 3 Replacement of bowman layer and epithelial basement membraneWith severe recurrent corneal errosion10Bowman layer dystrophies1. Reis Bucklers dystrophy ( CDB1, GCD type 3)Signs Grey white , fine ,round and polygonal subepithelial opacitiesIncrease with age Reduced corneal sensations

Treatment Directed at recurrent errosionsExcimer laser keratectomy

Increase and give rise reticular pattern due to laying down of irregular bands of collagen replacing bowmans layerLaser achieve satisfactory control in some patients11Bowman layer dystrophies2. Thiel-Behnke dystrophy(CDB2,honeycomb-shaped corneal dystrophy)Inheritance HistologyOnset End of 1st decadeRecurrent erosionsSigns Honeycomb subepithelial opacityTreatment

AD GENE loci 10q24 and 5q31 gene TGFB1Histologycurly fibres in bowman layer on electron microscopeSigns----involve central corneaTreatment----may not be necessary coz visual impairment is less than in ries-buckler12Bowman layer dystrophies3. Schnyder central crystalline dystrophyDisorder of corneal lipid metabolismInheritanceHistology Onset 2nd decade , visual imparementSigns Central ,oval, subepithelial crystalline opacityDiffuse corneal hazeProminent arcus in 3rd decadeTreatment

50% pt hav raised serum cholestrolAD gene loci on 1p36Histo---deposits of phospholipid and cholestrolTreatment---by excimer laser13Stromal dystrophies1. Lattice corneal dystrophy type 1(LCD1, Biber-Haab-Dimmer)Inheritance AD, 5q31Histology Amyloid stainGreen birefringence Onset End of 1st decade

Stain with congo redGreen bi with polarizing filter14Stromal dystrophiesLattice corneal dystrophy type 1

Signs Anterior stromal dotsFine lattice linesSpread Stromal hazeReduced sensationsTreatment PKP or DALK

In chronologic orderAnt stromal , glassy , refractile dotsCoalese into fine lattice lineDeep ane outward spread sparing peripheryGeneralised stromal haze progressively impair vision15Stromal dystrophies2. Lattice corneal dystrophy type 2 (LCD2,Finnish type amyloidosis, Meretoja syndrome)

Inheritance AD , gene locus 9q34Histology Amyloid deposits in stromaOnset 2nd decadeSigns fine lattice lines impaired corneal sensationsTreatment keratoplasty Randomly scattered , short, fine lattice lines, which are sparse, more delicate,more radially oriented , more peripherally located than LCD1Keratoplasty may rarely required in later life to improve vision16Stromal dystrophies3. Lattice corneal dystrophy type 3

Inheritance ADOnset 70 90 yearsSigns Thick rope like bands of amyloid

Stromal dystrophies4. Granular corneal dystrophy type 1 (GCD1 , Groenouw type 1)Inheritance Onset 1st decadeSigns Anterior stromal depositsDeeper and outward spreadImpaired corneal sensationsTreatment

Small well defined deposits like sugar granules , crumbs, rings or flakesHistology ---hyaline depositsPKP or DALK18Stromal dystrophies5. Granular corneal dystrophy type 2(GCD2, combined granular-lattice dystrophy)

Inheritance Onset 2nd decadeSignsSuperficial opacitiesDeeper linear opacities

AD gene locus 5q31Histoboth hyalin and amyloid deposits

Deeeper linear opacities reminiscent of lattice dystrophyTreatment usually not required19Endothelial dystrophies1. Fuchs endothelial dystrophy

Bilateral accelerated endothelial cell lossMore common in women

Inheritance ADOnset Old age, slow progressiveHistology Guttata

Assocated with slightly increased prevalence of open angle glaucomaGuttata==irregular excrescence of descement membPAS stain20Endothelial dystrophies1. Fuchs endothelial dystrophy

Signs Corneal guttataBeaten metal appearanceStromal edemaEpithelial edemaMicrocyst and bullae

Corneal guttata----refers to irregular warts of descement memb,secreted by abnormal endothelial cellsSpecular reflection show tiny dark spots due to disruption of regular endothelial mosaicProgression occurs to beaten metal appearanceEndothelial decompensation gradually lead to stromal edema and dec visionworsen in the morningEpithelal edema develop when stromal thickness >30%Persistant epithelial edema---microcyst and bullae which cause pain on rupturedue to nacked nerve endings21Endothelial dystrophies1. Fuchs endothelial dystrophyTreatment Conservative options0.5% topical sodium chlorideCorneal dehydrationBandage contact lensesPKP or DLEKOther optionsConjunctival flapAmniotic membrane transplantUse hair dryer to speed corneal dehydration in the morningBCL- to protect exposed nerve endings and flatten bullaeKeratoplasty-high success rateOther--- in eye with poor visual outcome

22Endothelial dystrophies2. Posterior polymorphous dystrophy (PPCD)

Innocuos asymptomatic Inheritance ADOnset - at birthSigns vesicular endothelial lesion band like or diffuseTreatment

RareOnset-may be incidently diagnosed later in lifeTreatment is not usually required23Endothelial dystrophies3. Congenital hereditary endothelial dystrophyFocal or generalized absence of corneal endotheliumTwo main forms CHED1 and CHED2Inheritance Onset perinatalSigns Corneal edemaOpacification

Type 1-AD ,,type 2 ARBilateral symmetrical diffuse corneal edema---resulting in blue grey ground glass appearance----to total opacification24Thank you

Recommended

View more >