corneal stromal dystrophies

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DR. ADITYA RAUT DR. ADITYA RAUT

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Page 1: Corneal Stromal Dystrophies

DR. ADITYA RAUTDR. ADITYA RAUT

Page 2: Corneal Stromal Dystrophies

The word The word dystrophy derived from the Greek (dys = wrong, difficult; dystrophy derived from the Greek (dys = wrong, difficult; trophe = nourishment)[1] was introduced into the ophthalmology trophe = nourishment)[1] was introduced into the ophthalmology

literature in 1890 by Arthur Groenouw when he published his classic literature in 1890 by Arthur Groenouw when he published his classic paper describing two patients with ‘Noduli Corneae.paper describing two patients with ‘Noduli Corneae.

The words ‘corneal dystrophy’ typically refer to a group of inherited The words ‘corneal dystrophy’ typically refer to a group of inherited corneal diseases that are usually bilateral, symmetric, slowly corneal diseases that are usually bilateral, symmetric, slowly

progressive and not related to environmental or systemic factors.’progressive and not related to environmental or systemic factors.’

Page 3: Corneal Stromal Dystrophies

IC3D classificationIn the new classification system, all corneal dystrophies have been categorized into 4 levels:

Category 1: a well-defined corneal dystrophy in which the gene has been mapped and identified and

specific mutations are known

Category 2: a well-defined corneal dystrophy that has been mapped to 1 or more specific chromosomal

loci, but the gene(s) remain(s) to be identified

Category 3: a well-defined corneal dystrophy in which the disorder has not yet been mapped to a

chromosomal locus;

Category 4: this category is reserved for a suspected new, or previously documented, corneal

dystrophy, although the evidence for it, being a distinct entity, is not yet convincing. The category

assigned to a specific corneal dystrophy can be expected to changeover time as knowledge

progressively advances

Eventually, all valid corneal dystrophies should attain the level of category 1; macular corneal dystrophy

is an example of a category 1 dystrophy. Conversely, over time and with further information, some

entities that are category 4 may be shown not to be distinct entities and may be removed

Page 4: Corneal Stromal Dystrophies

Template Used in this presentation

NAMENAME

AGE OF INCIDENCEAGE OF INCIDENCE

GENETICSGENETICS

SIGNS/SYMPTOMSSIGNS/SYMPTOMS

CLINICAL DIAGNOSISCLINICAL DIAGNOSIS

HISTOLOGY IN BRIEFHISTOLOGY IN BRIEF

Page 5: Corneal Stromal Dystrophies

Stromal dystrophiesStromal dystrophies 1 TGFBI corneal dystrophies A Lattice corneal dystrophy i Lattice corneal dystrophy, TGFBI type (LCD)

Classic lattice corneal dystrophy (LCD1) C1, variants (III, IIIA, I/IIIA, IV) are C1 ii Lattice corneal dystrophy, gelsolin type (LCD2) C1

This is not a true corneal dystrophy but is included here for ease of differential diagnosis

B Granular corneal dystrophy C1 i Granular corneal dystrophy, type 1 (classic) (GCD1) C1 ii Granular corneal dystrophy, type 2 (granular-lattice) (GCD2) C1 iii Granular corneal dystrophy, type 3 (RBCD) = Reis-Bücklers) C1

2 Macular corneal dystrophy (MCD) C1 3 Schnyder corneal dystrophy (SCD) C1 4 Congenital stromal corneal dystrophy (CSCD) C1 5 Fleck corneal dystrophy (FCD) C1 6 Posterior amorphous corneal dystrophy (PACD) C3 7 Central cloudy dystrophy of Francois (CCDF) C4 8 Pre-Descemet's corneal dystrophy (PDCD) C4

Page 6: Corneal Stromal Dystrophies

Granular dystrophy Type 1

Name / EponymsName / Eponyms : :

Granular dystrophy type 1/ Groenouw Dystrophy 1Granular dystrophy type 1/ Groenouw Dystrophy 1

Age of OnsetAge of Onset : :

11stst – 2 – 2ndnd decade of life ( early adolescence) decade of life ( early adolescence)

GeneticsGenetics : :

It is a TGFBI gene-related dystrophy, with a mutation of Arg555Trp at It is a TGFBI gene-related dystrophy, with a mutation of Arg555Trp at 5q31 gene locus and it is MIM 1219005q31 gene locus and it is MIM 121900Autosomal DominantAutosomal Dominant

First described by German ophthalmologist  Arthur Groenouw in 1890First described by German ophthalmologist  Arthur Groenouw in 1890..

Page 7: Corneal Stromal Dystrophies

Clinical Features and DiagnosisClinical Features and Diagnosis

Bilateral ,small, discrete, sharply demarcated, grayish-white opacities in the anterior Bilateral ,small, discrete, sharply demarcated, grayish-white opacities in the anterior central stromacentral stroma..Drop-shaped, crumb-shaped, and ring-shaped.Final appearance mayDrop-shaped, crumb-shaped, and ring-shaped.Final appearance may resemble christmas tree / popcornresemble christmas tree / popcorn . .Advanced stages give ground glass appearance of corneaAdvanced stages give ground glass appearance of cornea..

Slit Lamp ExaniationSlit Lamp Exaniation::Fine dots and radial lines in the superficial stromaFine dots and radial lines in the superficial stroma

May stain –ve with fluorescein and there may be areas of rapid tear filmMay stain –ve with fluorescein and there may be areas of rapid tear film breakupbreakup..

HistologyHistology::Stains to use – H & E stain , Masons TrichromeStains to use – H & E stain , Masons Trichrome

Recurrence after treatmentRecurrence after treatment: : Granular dystrophy can recur in the grafts as early as 1 year after surgery, and the Granular dystrophy can recur in the grafts as early as 1 year after surgery, and the recurrence-free interval seems to be independent of size and type of graftrecurrence-free interval seems to be independent of size and type of graft

performedperformedRecurrence pattern - central and superficial producing vortex patternRecurrence pattern - central and superficial producing vortex pattern..

Page 8: Corneal Stromal Dystrophies
Page 9: Corneal Stromal Dystrophies
Page 10: Corneal Stromal Dystrophies

Granular corneal dystrophy, type 2 (granular-lattice)

Name / EponymsName / Eponyms : :

Granular dystrophy type 2/ Combined granular-lattice corneal dystrophy, Granular dystrophy type 2/ Combined granular-lattice corneal dystrophy, Avellino corneal dystrophyAvellino corneal dystrophy

Age of OnsetAge of Onset : :

11stst – 2 – 2ndnd decade of life ( early adolescence) . Homozygous patients have decade of life ( early adolescence) . Homozygous patients have earlier onset, as early as 3 years of ageearlier onset, as early as 3 years of age..

GeneticsGenetics : :

It is a TGFBI gene-related dystrophy, with genetic locus at 5q31 and MIM It is a TGFBI gene-related dystrophy, with genetic locus at 5q31 and MIM number 607541. It is caused by an Arg124 His mutation in the βig-h3number 607541. It is caused by an Arg124 His mutation in the βig-h3 . .

Autosomal DominantAutosomal Dominant

The disorder was first described by Folberg et al. in 1988The disorder was first described by Folberg et al. in 1988

Page 11: Corneal Stromal Dystrophies

Clinical Features and DiagnosisClinical Features and Diagnosis

Anterior, stromal, discrete gray-white granular depositsAnterior, stromal, discrete gray-white granular deposits.;.;Mid to posterior stromal lattice lesionsMid to posterior stromal lattice lesions..Anterior stromal hazeAnterior stromal haze . .

Foreign body sensation, pain, and photophobiaForeign body sensation, pain, and photophobia

Slit lamp examinationSlit lamp examination: : Tiny whitish dots In anterior stroma, stellate ring or snowflake like opacities, deep Tiny whitish dots In anterior stroma, stellate ring or snowflake like opacities, deep stromal large lattice linesstromal large lattice lines..

HistologyHistology::Mixed deposits of amyloid and Hyaline. The amyloid stains red with Congo redMixed deposits of amyloid and Hyaline. The amyloid stains red with Congo red stain and the hyaline stains red with Masson Trichomestain and the hyaline stains red with Masson Trichome..  

Recurrence after treatmentRecurrence after treatment: :

Recurrent granular deposits have been noted in donor corneal tissue after Recurrent granular deposits have been noted in donor corneal tissue after penetrating keratoplasty for this conditionpenetrating keratoplasty for this condition

Page 12: Corneal Stromal Dystrophies
Page 13: Corneal Stromal Dystrophies
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Reis-Bücklers dystrophy (CDB) type I

Name / EponymsName / Eponyms : :

Granular dystrophy type 3,‘True’ Reis-Bücklers corneal dystrophy, Granular dystrophy type 3,‘True’ Reis-Bücklers corneal dystrophy, superficial granular dystrophy, corneal dystrophy of Bowman's layer type I, superficial granular dystrophy, corneal dystrophy of Bowman's layer type I, geographic corneal dystrophygeographic corneal dystrophy

Age of OnsetAge of Onset : :

11stst – 2 – 2ndnd decade of life. Sometimes even at 1 year of age. Usually at 4-5 decade of life. Sometimes even at 1 year of age. Usually at 4-5 years of ageyears of age . .

GeneticsGenetics : :

This variant of granular dystrophy is caused by a mutation in βig-h3 This variant of granular dystrophy is caused by a mutation in βig-h3 (Arg124Leu; Arg555Gln)(Arg124Leu; Arg555Gln) . .

Autosomal DominantAutosomal Dominant

The disorder was first described by Folberg et al. in 1988The disorder was first described by Folberg et al. in 1988

Page 15: Corneal Stromal Dystrophies

Clinical Features and DiagnosisClinical Features and Diagnosis

Patchy geographic opacities at the level of Bowmans membrane. Elevated Patchy geographic opacities at the level of Bowmans membrane. Elevated epithelium leading to epithelial erosionsepithelium leading to epithelial erosions..Hyperaemia, pain, photophobiaHyperaemia, pain, photophobia..

Slit lamp examinationSlit lamp examination: : Elevated epithelium. Reticular pattern of cloudiness. Irregular bowmans membraneElevated epithelium. Reticular pattern of cloudiness. Irregular bowmans membrane

Significant vision lossSignificant vision loss . .No vascularization of corneaNo vascularization of cornea..

HistologyHistology::Masons Trichrome Stain.Masons Trichrome Stain. red stained deposits of mutated red stained deposits of mutated transforming growth transforming growth factor beta-induced proteinfactor beta-induced protein in the superficial corneal stroma in the superficial corneal stroma  

Recurrence after treatmentRecurrence after treatment: :

Recurrence is common after treatmentRecurrence is common after treatment..

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Page 17: Corneal Stromal Dystrophies

Macular Corneal Dystrophy

Name / EponymsName / Eponyms : :

Groenouw corneal dystrophy type II; Fehr spotted dystrophyGroenouw corneal dystrophy type II; Fehr spotted dystrophy

Age of OnsetAge of Onset : :

11stst decade of life. Usually from 3-9 years decade of life. Usually from 3-9 years..

GeneticsGenetics : :

Autosomal recessive traitAutosomal recessive trait..Chromosome 16 (16q22.1)Chromosome 16 (16q22.1),,Keratan Sulfate – Three typesKeratan Sulfate – Three types..

Mutation in carbohydrate sulfotransferase gene (CHST6) has been Mutation in carbohydrate sulfotransferase gene (CHST6) has been identified as the cause of macular dystrophyidentified as the cause of macular dystrophy..

Page 18: Corneal Stromal Dystrophies

Clinical Features and DiagnosisClinical Features and Diagnosis

Diffuse, fine, superficial clouding in the central stromaDiffuse, fine, superficial clouding in the central stroma.. Multiple, irregular, dense, gray-white nodules with indistinct borders can protrude Multiple, irregular, dense, gray-white nodules with indistinct borders can protrude

anteriorlyanteriorly..Corneal periphery, deep posterior focal plaques, grayness, and a guttate Corneal periphery, deep posterior focal plaques, grayness, and a guttate appearance of Descemet's membrane may be seenappearance of Descemet's membrane may be seen

HistologyHistology::

The glycosaminoglycans stain with Alcian blue, colloidal iron, metachromatic dyes, The glycosaminoglycans stain with Alcian blue, colloidal iron, metachromatic dyes, and PASand PAS

Recurrence after treatmentRecurrence after treatment: :

Recurrence involves peripheral donor stroma in the superficial and deep layers. Recurrence involves peripheral donor stroma in the superficial and deep layers. Host keratocytes invade the graft and produce abnormal glycosaminoglycanHost keratocytes invade the graft and produce abnormal glycosaminoglycan..

Size of the graft seems to be inversely related to the recurrenceSize of the graft seems to be inversely related to the recurrence..

Page 19: Corneal Stromal Dystrophies
Page 20: Corneal Stromal Dystrophies

Lattice Dystrophy classic and variants

Name / EponymsName / Eponyms : :

Biber-Haab-Dimmer dystrophy

Age of OnsetAge of Onset : :

Type I - 1Type I - 1stst decade of life decade of life..Type III – 60 – 80 years of ageType III – 60 – 80 years of age..

GeneticsGenetics : :

Lattice corneal dystrophy type I - autosomal dominantLattice corneal dystrophy type I - autosomal dominantmutations at 5q31 genemutations at 5q31 gene Lattice corneal dystrophy type III - autosomal recessive disorderLattice corneal dystrophy type III - autosomal recessive disorder , ,The gene has not yet been mappedThe gene has not yet been mapped . .

Lattice corneal dystrophy type IIIA - autosomal dominant pattern, Lattice corneal dystrophy type IIIA - autosomal dominant pattern, mutation at 5q31 genemutation at 5q31 gene..

Lattice corneal dystrophy type IV – autosomal dominantLattice corneal dystrophy type IV – autosomal dominantLeu527Arg mutation in the βig-h3Leu527Arg mutation in the βig-h3..

Page 21: Corneal Stromal Dystrophies

Clinical Features and DiagnosisClinical Features and Diagnosis

Type IType IBilateral, inherited, primary, localized corneal amyloidosisBilateral, inherited, primary, localized corneal amyloidosis..Round subepithelial opacities, anterior stromal white dots, and small refractile filamentary linesRound subepithelial opacities, anterior stromal white dots, and small refractile filamentary lines..Diffuse central anterior stromal hazeDiffuse central anterior stromal haze..

Progression -> small nodules, dots, threadlike spicules, or thicker, radially oriented branching Progression -> small nodules, dots, threadlike spicules, or thicker, radially oriented branching lineslines . .

Type IIIType IIILate onset of decreasing vision, no recurrent epithelial erosions, and lattice lines much thickerLate onset of decreasing vision, no recurrent epithelial erosions, and lattice lines much thickerThick, midstromal, lattice-like lines that extend from limbus to limbusThick, midstromal, lattice-like lines that extend from limbus to limbus

Slit Lamp ExaminationSlit Lamp Examination::Lattice lines are typically refractile with a double contour and a clear core on retroilluminationLattice lines are typically refractile with a double contour and a clear core on retroillumination . .

Filaments - opaque with irregular margins, radially oriented with dichotomous branching near Filaments - opaque with irregular margins, radially oriented with dichotomous branching near their central terminationstheir central terminations

HistologyHistology::PAS stain PAS stain - Eosinophilic layer separating the epithelial basement membrane from Bowman's - Eosinophilic layer separating the epithelial basement membrane from Bowman's layer is present and is composed of amyloid and collagelayer is present and is composed of amyloid and collage

Irregular, eosinophilic deposits in stromaIrregular, eosinophilic deposits in stroma..Central, superficial corneal stroma - crater-like appearance with fine, short, Central, superficial corneal stroma - crater-like appearance with fine, short, branching or branching or criss-crossing linescriss-crossing lines

RecurrenceRecurrence::Recurs more frequently as compared to others. May recur as soon as 3 years after Recurs more frequently as compared to others. May recur as soon as 3 years after keratoplastykeratoplasty..

Page 22: Corneal Stromal Dystrophies

Fine, spidery, branching lines within stroma.

Later general haze may submerge lesions.

Progression

Page 23: Corneal Stromal Dystrophies
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Thick translucent lattice lines, diffuse subep. opacities.

Lattice dystrophy type III

Page 25: Corneal Stromal Dystrophies

Lattice Dystrophy gelsolin typeName / EponymsName / Eponyms : :

Familial amyloidosis, Finnish (FAF); Meretoja's syndrome, amyloidosis Familial amyloidosis, Finnish (FAF); Meretoja's syndrome, amyloidosis V,familial amyloidotic polyneuropathy IVV,familial amyloidotic polyneuropathy IV

Age of OnsetAge of Onset : :

20-3520-35 yearsyears

HistologyHistology::A regular amyloid layer lies beneath a normal-appearing Bowman's A regular amyloid layer lies beneath a normal-appearing Bowman's membrane, in contrast to type I in which Bowman's membrane is membrane, in contrast to type I in which Bowman's membrane is disrupteddisrupted..

GeneticsGenetics : :

This variety of lattice dystrophy is caused by mutations in the gelsolinThis variety of lattice dystrophy is caused by mutations in the gelsolin gene (GSN) on the long arm of chromosome 9 (9q34)gene (GSN) on the long arm of chromosome 9 (9q34)..

Page 26: Corneal Stromal Dystrophies

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

palsiesSkin Dry, itchy, and lax with

amyloid deposits Renal and cardiac failure.

Cornea:

Few thick lines; extend to Few thick lines; extend to periphery; few amorphous depositsperiphery; few amorphous deposits

Page 27: Corneal Stromal Dystrophies

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

Page 28: Corneal Stromal Dystrophies

Schnyders Crystalline Dystrophy

Name / EponymsName / Eponyms : :

Crystalline stromal dystrophyCrystalline stromal dystrophySchnyder crystalline dystrophy sine crystalsSchnyder crystalline dystrophy sine crystalsHereditary crystalline stromal dystrophy of SchnyderHereditary crystalline stromal dystrophy of SchnyderSchnyder's crystalline corneal dystrophySchnyder's crystalline corneal dystrophy

Age of OnsetAge of Onset : :

22ndnd Decade of life Decade of life

GeneticsGenetics : :

Autosomal dominant trait. It is caused by heterozygous mutations Autosomal dominant trait. It is caused by heterozygous mutations in UBIAD1 genein UBIAD1 gene..

Page 29: Corneal Stromal Dystrophies

Clinical Features and DiagnosisClinical Features and Diagnosis

Bilateral gray, disc-like opacities – anterior stromaBilateral gray, disc-like opacities – anterior stroma..Often central, fine polychromatic cholesterol crystals in the anterior stromaOften central, fine polychromatic cholesterol crystals in the anterior stromaGeographic, annular, or disciform pattern and may extend to the deeper stromal Geographic, annular, or disciform pattern and may extend to the deeper stromal layerslayers

Arcus lipoides or senilis is often a prominent finding in the peripheral cornea in Arcus lipoides or senilis is often a prominent finding in the peripheral cornea in patients over the age of 23 with this dystrophypatients over the age of 23 with this dystrophy..

Clinical VariationsClinical Variations))11 ( (a central discoid lesion without crystalsa central discoid lesion without crystals ; ;

))22 ( (a crystalline discoid central lesion with a garland-like margina crystalline discoid central lesion with a garland-like margin;;) ) 33 ( (a crystalline discoid central lesion with a poorly defined edgea crystalline discoid central lesion with a poorly defined edge;;

) ) 44 ( (a crystalline annular opacity with a clear center; anda crystalline annular opacity with a clear center; and) ) 55 ( (an annular opacity with crystal collections and a clear centeran annular opacity with crystal collections and a clear center..

HistologyHistology::The stroma demonstrates focal round empty spaces . Oil red O or Sudan blackThe stroma demonstrates focal round empty spaces . Oil red O or Sudan black stainstain..

Recurrence after treatmentRecurrence after treatment: : Recurrence of cholesterol crystals may occur in both lamellar or penetrating graftsRecurrence of cholesterol crystals may occur in both lamellar or penetrating grafts..

Page 30: Corneal Stromal Dystrophies
Page 31: Corneal Stromal Dystrophies

Fleck dystrophy(François-Neetens)

Name / EponymsName / Eponyms : :

Francois-Neetens speckled corneal dystrophyFrancois-Neetens speckled corneal dystrophy

Age of OnsetAge of Onset : :

Very Early. ? CongenitalVery Early. ? Congenital

GeneticsGenetics : :Autosomal DominantAutosomal DominantIt is caused by mutations in PIKFYVE geneIt is caused by mutations in PIKFYVE gene..

Page 32: Corneal Stromal Dystrophies

Clinical Features and DiagnosisClinical Features and Diagnosis

Visual acuity unaffected. PhotophobiaVisual acuity unaffected. Photophobia..Grayish specks are in all layersGrayish specks are in all layers oval,rounded, Comma,stellate oval,rounded, Comma,stellate..

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

HistologyHistology::Glycosaminoglycans are demonstrated with Alcian blue or colloidal iron stains, and Glycosaminoglycans are demonstrated with Alcian blue or colloidal iron stains, and the lipids with Sudan black B and oil red O stainsthe lipids with Sudan black B and oil red O stains

Page 33: Corneal Stromal Dystrophies
Page 34: Corneal Stromal Dystrophies

Central Cloudy Dystrophy (François')

Name / EponymsName / Eponyms : :

No other nameNo other name..

Age of OnsetAge of Onset : :

Childhood . 1Childhood . 1stst decade of life decade of life . .

GeneticsGenetics : :Autosomal DominantAutosomal Dominant

Page 35: Corneal Stromal Dystrophies

Clinical Features and DiagnosisClinical Features and Diagnosis

•Nonprogressive dystrophy with faint, cloudy, gray snowflake-like lesions with ill- defined edges deep in the stroma.•Clear intervening stromal linesmosaic pattern.•Do not involve the superficial stroma and do not extend to the periphery.•Polygonal (cracked ice) in shape•The stroma is of normal thickness, and no loss of sensation has been noted.•The epithelium is uninvolved, and erosions do not occur. •Clinically, the lesions are identical to those in posterior crocodile shagreen.

HistologyHistology::The pathologic abnormality has yet to be elucidated. The abnormal collagen found The pathologic abnormality has yet to be elucidated. The abnormal collagen found in posterior crocodile shagreen may represent the same defectin posterior crocodile shagreen may represent the same defect..

Page 36: Corneal Stromal Dystrophies

Central Cloudy Dystrophy (François')

Page 37: Corneal Stromal Dystrophies

Posterior Amorphous Corneal Dystrophy (PACD)

Name / EponymsName / Eponyms : :

No other nameNo other name..

Age of OnsetAge of Onset : :

Neonatal . InfancyNeonatal . Infancy . .

GeneticsGenetics : :Autosomal DominantAutosomal Dominant

Page 38: Corneal Stromal Dystrophies

Clinical Features and DiagnosisClinical Features and Diagnosis

Bilateral, congenital, inherited opacificationBilateral, congenital, inherited opacificationNonprogressive or slowly progressiveNonprogressive or slowly progressiveDisordered stromal fibrogenesisDisordered stromal fibrogenesis..

A diffuse haze made up of flaky lesions is seen primarily in the central anterior A diffuse haze made up of flaky lesions is seen primarily in the central anterior stroma, but also may involve the deeper layers. The lesions are often less dense stroma, but also may involve the deeper layers. The lesions are often less dense

peripherallyperipherally . .The epithelium is intact without erosions, edema, or decreased sensation. Visual The epithelium is intact without erosions, edema, or decreased sensation. Visual acuity is depressed, and dense amblyopia and searching nystagmus may developacuity is depressed, and dense amblyopia and searching nystagmus may develop..

Esotropia also has been reportedEsotropia also has been reported..

HistologyHistology::The epithelium and Bowman's layer are uninvolvedThe epithelium and Bowman's layer are uninvolved . .

Abnormalities of the stromal lamellae are noted, with clefting and layering. All Abnormalities of the stromal lamellae are noted, with clefting and layering. All collagen fibrils in the stroma have a diameter of about 15 nm, which is one-half the collagen fibrils in the stroma have a diameter of about 15 nm, which is one-half the normal diameter of 30 nmnormal diameter of 30 nm..

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Page 40: Corneal Stromal Dystrophies

Pre-Descemet Corneal Dystrophy (PDCD)

Name / EponymsName / Eponyms : :

No other nameNo other name..

Age of OnsetAge of Onset : :

33rdrd Decade of life Decade of life..

GeneticsGenetics : :Inheritance UnknownInheritance Unknown

Page 41: Corneal Stromal Dystrophies

Clinical Features and DiagnosisClinical Features and Diagnosis

In pre-Descemet's dystrophy, focal fine gray dots are seen in the posterior stroma In pre-Descemet's dystrophy, focal fine gray dots are seen in the posterior stroma in a variety of punctate and linear shapesin a variety of punctate and linear shapes

Less commonly, larger lesions occur with circular, comma, boomerang, wormlike, Less commonly, larger lesions occur with circular, comma, boomerang, wormlike, and dendritic shapesand dendritic shapes

These lesions are most often bilateral and symmetric and occur after age 30. They These lesions are most often bilateral and symmetric and occur after age 30. They may be diffuse, central, or form a ring, sparing the peripheral and central cornea. may be diffuse, central, or form a ring, sparing the peripheral and central cornea. Visual acuity is usually not affectedVisual acuity is usually not affected..

HistologyHistology::Curran et al. described a single case with a normal cornea except for enlarged Curran et al. described a single case with a normal cornea except for enlarged keratocytes near Descemet's membrane, which contained PAS-positive material keratocytes near Descemet's membrane, which contained PAS-positive material and vacuolation. This abnormal material also stained for lipid with oil red O, Sudan and vacuolation. This abnormal material also stained for lipid with oil red O, Sudan black B, and Baker's phospholipidblack B, and Baker's phospholipid..

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ManagementTherapeuticTherapeuticRecurrent epithelial erosions should be managed routinely with therapeutic contact lensesRecurrent epithelial erosions should be managed routinely with therapeutic contact lenses

,,artificial tears and hypertonic saline. In case of photophobia tinted contact lenses can be artificial tears and hypertonic saline. In case of photophobia tinted contact lenses can be usedused . .

Debridement can be done in cases with recalcitrant erosions in reis buckler dystrophyDebridement can be done in cases with recalcitrant erosions in reis buckler dystrophyLipid profile must be done in cases of crystalline dystrophyLipid profile must be done in cases of crystalline dystrophy..

SurgicalSurgical

Surgical management varies based on the depth and extent of the stromal lesions. TheSurgical management varies based on the depth and extent of the stromal lesions. Thetraditional surgical approach has been penetrating keratoplasty, which is uncommonlytraditional surgical approach has been penetrating keratoplasty, which is uncommonlyperformed before the fifth decadeperformed before the fifth decade..

If the opacities are extremely superficial, epithelial scraping, superficial keratectomyIf the opacities are extremely superficial, epithelial scraping, superficial keratectomy,,or lamellar keratoplasty can be performedor lamellar keratoplasty can be performed

Phototherapeutic keratectomy (PTK) with the argon-fluoride excimer laser has beenPhototherapeutic keratectomy (PTK) with the argon-fluoride excimer laser has beenused to treat superficial granular dystrophy with good resultsused to treat superficial granular dystrophy with good results

With deeper stromal lesions and significant visual loss, penetrating keratoplasty is theWith deeper stromal lesions and significant visual loss, penetrating keratoplasty is theindicated procedureindicated procedure..

Phototherapeutic keratectomy has been used in early stages of macular dystrophyPhototherapeutic keratectomy has been used in early stages of macular dystrophy..