BY:BY:

DR. SAFAA REFAATDR. SAFAA REFAATFRCSG Ophth, MSc, FRCSG Ophth, MSc,

MBBSMBBS

CORNEAL DYSTROPHIES

Hereditary disorders that progressively affect the

central part of both corneas & are not associated with

inflammation.

CORNEAL DYSTROPHIES

A-EP.& B.M. DYSTOPIES:• Epithelial.• Epithelial B.M.B-STROMAL DYSTROPHIES:• Bowman’s layer• Stroma • Pre Descmet’sC-ENDOTHELIAL DYSTROPHY

CORNEAL DYSTROPHIESA-EP.& B.M. DYSTOPIES:

1. Ep: Mesman’s dystrop 2. Ep.B.M.: Map/Dot/finger print

B-STROMAL DYSTROPHIES:

Bowman’s layer: 1. Reis-Bücklers dystrophy (CDB) I 2. Honeycomb-shaped dystrophy (CDB) II 3. Anterior membrane dystrophy of Grayson-

Wilbrandt.4. Subepithelial mucinous corneal dystrophy.

Stroma:

1. Granular.2. Lattice dystrophy (I,III,IIIA,& IV) 3. Macular I & II4. Avellino’s Dystrophy. 5. Gelatinous Droplike Dystrophy 6. Central Crystalline Dystrophy (Schnyder's)7. Marginal Crystalline Dystrophy (Bietti's) 8. Central Cloudy Dystrophy (François') 9. Fleck dystrophy(François-Neetens)10. Parenchymatous dystrophy of Pillat 11. Posterior Amorphous Stromal Dystrophy 12. Congenital Hereditary Stromal Dystrophy

Pre Descmet’s:

1. Cornea farinata

2. Grayson-Wilbrandt Dystrophy

3. Deep Filiform Dystrophy

C-ENDOTHELIAL DYSTROPHY

1. Congenital hereditary corneal dystrophy

2. Fuchs' Dystrophy (Late Hereditary Endothelial Dystrophy)

3. Posterior Poly morphous dystrophy

A-EP.& B.M. DYSTROPHIES:

1. Epithelial: Meesman’s dyst. AD. 1st few mo. Symptoms 4th decade Intraepithelial

pseudocyst containing desquamated cellular debris.

2.Ep.B.M.:Map/Dot/finger print (A.B.M.)

AD

Sporadic

2nd 3rd decade

The most common dyst.

Most common cause of REE.

Irregular astigmatism.

Dots

Fingerprints

Cysts

Maps

Four types of lesions - in isolation or combinationMicrocystsDots

Maps Fingerprints

Signs of Cogan dystrophy

Pathology of A.B.M.D.

Abnormal multilaminar BMintra epithelially blocks the normal migration of epithelial cells Trapped epithelial cells microcysts & dots

Abnormal BM Map & Fingerprints.

(Treatment)•Débridement . •Superficial keratectomy.•Lubricants, hypertonic saline-bandage soft CL.•Anterior stromal reinforcement or puncture.• PTK .

B-STROMAL DYSTROPHIES:BOWMAN’S LAYER:

1.Reis-Bücklers dystrophy (CDB) type I

•AD•1st 2nd decade.•Patchy geographic opacities at the level of BM central reticulated opacities with stromal haze.• Peripheral cornea spared.•Sensation diminished.

Reis-Bucklers dystrophy..

Painful REE.Attacks typically occurs 5 times / y. Stabelize after 3rd decade. VA decreased.

Treatment.....………………………....................................

2. Honeycomb-shaped dystrophy of Thiel and Behnke.

•(CDB) type II.•AD - Childhood•Fragmentation of the collagen fibrils of Bowman's layer.

3.Anterior membrane dystrophy of Grayson- Wilbrandt.

ADVarient of Reis-Bücklers 10-11y.-In Japanese bilateral ring shaped corneal opacities at adolescenceGray-white mound-like opacities, protruding into the ep. Sparing the periphery

4. Subepithelial mucinous corneal dystrophy

AD

Early childhood REE

Diffuse homogenous sub ep. Hase & gray white patches fading toward the limbus.

STROMA1.Granular Dystrophy (Groenouw's Type I)

AD.

Onset Early adolescence with REE

Sharply demarcated, milky, opaque lesions resembling snowflakes or bread crumbs. intervening cornea is clear

Superficial & extend more posteriorly during evolution.

Clinical varientsDense axial non translucent gray-white deposits simulating bread crumbs More discrete and well-defined round and oval shapes, clear stroma. Christmas tree–like opacities with anterior stromal scarring. Pathol.: Irregularly shaped hyaline deposits within Bowman's layer and anterior stroma.

2.Lattice dystrophy(primary corneal amyloidosis)

I II III & IV.

AD >10 y.No systemic associationREEVA impaired 40-60 y

AD < 20 y.Systemic associationREEVA good until 65y

III AR , <40y.III A AD, 70-90 y.No systemic

associationNo REE VA impaired after 60y

Lattice dystrophy type I

Fine, spidery, branching lines within stroma.

Later general haze may submerge lesions.

Progression

Lattice dystrophy type II(Familial amyloidosis with lattice dystrophy, Meretoja syndrome)

Mask-like facies

Mask-like faciesl Blepharochalasis, Floppy ears Protruding lips Cranial and peripheral

nerve palsiesSkin Dry, itchy, and

lax with amyloid deposits

Renal and cardiac failure.

Thick translucent lattice lines, diffuse subep. opacities.

Lattice dystrophy type III

3.Macular Dystrophy(Groenouw's Type II( AR

(3-9y(

Initial dense, poorly delineated opacities

Later generalized opacification

Thinning

Progression

PATHOLOGY•Central superficial cloudeness progress entire corneal width & thickness gray illdefined denser opacities appear within this sea of hazinessProtrudes: -ant.irregular surface. - post. irregular descmet's with guttate appearance.

CCC.•Corneal thinning. •Localized mucopolysaccharidosis •primary involvement of end. &descmet’s

4. Avellino’s Dystrophy.

AD1st&2nd decade 1-Anterior stromal granular deposits2-mid to posterior stromal lattice lesions3-anterior stromal hase

Hyaline and amyloid deposition

4th & 5th Decade REE

5.Gelatinous Droplike Dystrophy

(primary familial amyloidosis of the cornea( AR1st decade Amyloid interposed between the epithelium and Bowman's layer.PHOTOPHOBIA & LACRIMATION VA..

6.Central Crystalline Dystrophy (Schnyder's(

AD

2nd Decade

polychromatic crystals.in Bowman's layer and the anterior stroma

Neutral fats and cholesterol

cholesterol and lipid studies is important .

7. Marginal Crystalline Dystrophy (Bietti's( AD

Crystalline deposits in the paralimbal anterior stroma

associated with a retinal pigmentary abnormality

AD Axial, posterior, cloudy

opacities. Clear intervening stromal

linesmosaic pattern. Association PEX

8.Central Cloudy Dystrophy (François'(

9.Fleck dystrophy(François-Neetens(

AD rare

very early, ? congenital.

Grayish specks are in all layers oval,rounded, Comma,stellate.

Associations Keratoconus, angioid streaks, pappillitis, limbal dermoid, punctuate cortical lens opacities.

10.Parenchymatous dystrophy of Pillat:AD very rare 6th decadeDeep stromal opacities (punctate or filamentous(

11.Posterior Amorphous Stromal Dystrophy 4 mo. , at birthGray amorphous sheet like opacities involving the stroma posteriorly clear intervening stroma thinningAss. Iris & angle abnormalties.

12.Congenital Hereditary Stromal Dystrophy:ADCongenitalFeathery clouding of the stroma.

Pre Descmet’s1.Cornea farinata:?

Small gray punctate opacities

association with ichthyosis 2.Grayson-Wilbrandt

Dystrophy:Pleomorphic opacities larger and more diffusely scattered than those

in cornea farinata. 3. Deep Filiform Dystrophy:

Middle-aged woman with keratoconus

multiple filiform gray opacities

sparing the perilimbal region.

C-ENDOTHELIAL DYSTROPHY:

1. Congenital hereditary endothelial dystrophy.

2. Fuchs' Dystrophy (Late Hereditary Endothelial Dystrophy(

3. Postrior Poly morphous dystrophy

1.Congenital hereditary corneal dyst.AR at birth nonprogres-sive, Nys-tagmus is common.

AD first or second year of life progressive, photophobia and tearing.No nystagmus.

Diffuse corneal edema

Thinning or Uniform thickening of Descemet's membrane but no guttata

Rule out congenital glaucoma A combination may occur.

Guttata

Peripheral Hassall-Henle bodiesCentral & numerous guttatSecondary cornea guttata.

Beaten-metal appearance of Descemet's membrane excrescences abnormal basement membrane and fibrillar collagens by distressed or dystrophic endothelial cells. with brownish pigmentation

2.Fuchs endothelial dystrophy

Eventually bullous keratopathy

Later central stromal oedema

Gradual increase in cornea guttata with peripheral spread

Progression

AD 5th 6th decade

Edema starts axially peripherally Discrete (guttate) and diffuse thickening of

Descemet's membrane

PATHOLOGY

Progressive deterioration of the endothelial function.

Abnormal basement membrane adhesion complexes breaks in Bowman's layer, subepithelial debris and fibrovascular pannus.

Diffuse thickening of Descemet's membrane (20 µm or more) and posteriorly projecting excrescences .

• Subtle, vesicular, geographic, or band-like lesions• Frequently asymmetrical

3.Posterior polymorphous dystrophy

AD

POLYMORPHOUS OPACITIES VESICULAR OR ANNULAR WITH SURROUNDING HALOS

PAS.

Normal VA , Usually No stromal edema or vascularization.

? Endothelial decompensation.

Posterior polymorphous dystrophy

An aberrant differentiation of the neural crest as in ICES Endothelial cells morphologically and immunopathologically resemble epitheliumEM myriad microvilli

CORNEAL DYSTROPHIES

ALL ARE AD EXCEPT:Lattice type III ARMacular ARGelatinous ARCongenital hered.end. dyst. AR (one

variant)

Mesman’s AR is recordedABMD sporadic is recorded

GENETICS

Big-h3 L :5 q31 (Human TGF beta induced gene ,kerato-epithelin) :Reis Buckler’s GranularLatticeAvellino