This document summarizes various corneal dystrophies. It discusses lattice corneal dystrophy types 1 and 2, which are caused by mutations leading to amyloid deposition. It presents the clinical features, histopathology, treatment and prognosis. Macular dystrophy is outlined as being caused by glycosaminoglycan accumulation. Other dystrophies mentioned include Schnyder corneal dystrophy, congenital hereditary stromal dystrophy, and posterior polymorphous corneal dystrophy. Fuchs endothelial dystrophy is described in detail, including its inheritance, symptoms, signs, course of disease, and treatment options such as transplantation.

1. CORNEAL DYSTROPHIES
(CONTINUED…)
Presenter- Dr Harshitha K M
Moderator- Dr Usha B R

2. LATTICE DYSTROPHY
• TYPES- Type 1- classic, Type 2- Gelsolin
• LCD type I:
– Classic Lattice Corneal Dystrophy/Biber-Haab-
Dimmer
– TGFB1 gene mutation-5q31 gene locus. (AD
inheritance)
– Isolated amyloid deposition in the stroma in a linear
pattern

3. CLINICAL FEATURES
 Manifests in 1st or 2nd decade with
apparence of thin branching
refractile lines and/or
subepithelial, whitish, ovoid dots.
 The lines start centrally and more
superficially , spreading
centrifugally and deeply but
leaving the periferal 1mm and
Descemet’s membrane
&endothelium clear

4. Progression
Fine, spidery, branching lines
within stroma.
Later general haze
(ground glass
apparence ) may
submerge lesions.

5. HISTOPATHOLOGY
 Amyloid stains intensely with Congo Red, shows
birefringence and dichroism.

6.  Electron miscroscopy shows fine filaments 8 to 10 nm
intermingled with collagenous fibers
 In Vivo confocal microscopy shows linear and branching
structures in the stroma with changing reflectivity and poorly
demarcated margins

8. TREATMENT
 Recurrent erosions  patching, hypertonic agents,
artificial tears or therapeutic contact lens
 Excimer laser PTK- optional treatment
 If vision is impaired  lamellar /penetrating
keratoplasty
 Recurrence after PK- early ( about 3 years)

9. LATTICE CORNEAL DEGENERATION- TYPE 2
 Gelsolin type /Finnish type/ familial amyloidosis/
Meretoja syndrome .
 Mutation of gelsolin gene- 9q34.
 Gelsolin is an actin filament modulating protien with
an actin-regulating domain found in leucocytes,
platelets and other cells.
 The amyloid protien in this type of LCD is a
fragment of actin filament binding region of a
variant gelsolin molecule.

10. CLINICAL FEATURES
 3rd to 4th decade
 Recurrent epithelial erosions
 Vision loss is less compared to other LCD.
 SLE- fewer more periferal lattice lines in corneal
stroma spreading centripetally from the limbus.
 Central cornea is relatively spared .
 Systemic features : Cranial and peripheral
neuropathies- facial paresis, bulbar palsy,
lagophthalmos and autonomic nervous dysfunction.
Lax skin, nephrotic syndrome, renal failure and
cardiomyopathy.

11. HISTOPATHOLOGY
 Amyloid is deposited in the cornea in lattice lines as a
discontinuous band under the bowmans layer .
 Deposition of gelsolin is also detected in conjunctiva,
sclera, stroma of ciliary body, along chorio capillaries

12. MACULAR DYSTROPHY
 Slowly progressive
 Autosomal recessive trait
 N acetyl glucosamine 6 sulfotransferase gene
(CHST6 gene) on chromosome 16q 21
 Pathogenesis- ? Incomplete glycosaminoglycan
sulfation

13. CLINICAL FEATURES
 1st and 3rd decade
 Diffuse stromal haze intially affecting the central cornea,
then extending till the limbus
 Later superficial central elevated irregular whitish
opacities(macules) develop
 NO CLEAR AREAS between the opacities.
 Lesions are more posterior peripheral white lesions.
 The cornea is thinner than normal in early disease and
is probably due to close packing of collagen fibrils.
 In late stages endothelium is affected, guttae+
 Reccurent corneal erosions also +

14. MACULAR DYSTROPHY

15. HISTOPATHOLOGY
 GAGs stain with Alcian blue, PAS, metachromatic
dyes and colloidal iron.
 Accumulate intracellularly and extracellularly in the
corneal stroma as well as in the DM.

16.  The extracellular matrix observed in electron microscopy
contains clumps of fibrogranular material staining positively for
GAGs while keratocytes also stain positive for GAGs.

17. TREATMENT
 PK is the treatment of choice.
 Reccurences are common
 Perifery of the graft is the most affected as the
keratocytes invade its superficial and deeper layers.

18. SCHNYDER CORNEAL DYSTROPHY
 Schnyder crystalline corneal dystrophy
 Rare
 1p36 chromosome
Clinical features :
 Presents early in life
 Central discoid opacity just posterior to the bowman’s
membrane, in the anterior stroma.
 Opacity consists of small, needle shaped refractile
crystals with glass wool appearance.
 May be associated with hyperlipoprotienemia
 Vision decreases with age.

22. CONGENITAL HERIDITARY STROMAL
DYSTROPHY
 Non progressive, heriditary, congenital, bilateral
 Pathogenesis- ? Disordered stromal fibrinogenesis
 12q22
Clinical features:
 @birth, diffuse bilateral corneal clouding with flake like,
whitish opacities, both equally distributed through out the
stroma.
 Epithelium and endothelium are normal
 Stromal thickness is not increased.
 NO signs of vascularization.
 Moderate to severe visual loss, amblyopia and nystagmus
may develop.
 Recurrence after PK is rare

26. DESCEMET’S MEMBRANE AND ENDOTHELIAL
DYSTROHIES
1. Posterior polymorphous corneal dystrophy
2. congenital heriditary endothelial dystrophy
3. Fuch’s endothelial dystrophy

27. POSTERIOR POLYMORPHOUS CORNEAL
DYSTROPHY (PPCD)
 Schlichting dystrophy
 Typically non progressive
 VSX1 and COL8A2
Clinical features:
Clinically classified into 3 main forms
Vesicular , band and diffuse.
Vesicles- appear as endothelial blisters or blebs on SLE ,
may be isolated or in clusters or curvilinear patterns
Bands – strips of guttae like irregularities in DM
Diffuse- diffuse irregularities in DM

28.  Periferal iridocorneal adhesions and rarely
secondary sub epithelial band keratopathy may be
seen
 Glaucoma and keratoconus- associations.
 D/D- ICE syndrome, however sporadic and
unilateral involvement of ICE are distinguishing
factors.

29. POSTERIOR POLYMORPHOUS DYSTROPHY

30. HISTOPATHOLOGY
 Descemet’s membrane consists of abnormal anterior band
and an abnormal posterior collagenous layer.
 In the periphery the endothelial cells show metaplasia and
epithelialization with desmosomal attachments, microvilli and
intermediate filaments.

33. CONGENITAL HERIDITARY ENDOTHELIAL
DYSTROPHY
 Rare cause of congenital corneal edema
 CHED 1(AD) and CHED 2 (AR)
Clinical features:
 Recessive CHED is more common with diffuse corneal
clouding being present at birth
 Nystagmus is often present
 B/l symmetrical, gray blue, ground glass haziness of the
corneal stroma extending to the limbus with no
intervening clear zones.
 Associated marked corneal thickening (2x to 3x)
 Rarely congenital glaucoma may co exist.

35. HISTOPATHOLOGY
 DM- diffuse thickening and lamination
 Endothelial cells are spare and atrophic
 On electron microscopy- multiple layers of
basement membrane like material can be seen
within posterior collagenous layer of DM.

36. FUCHS ENDOTHELIAL DYSTROPHY
•1910 Fuch’sgave first clinical description- as the most
common primary disorder of corneal endothelium
• Bilateral ,non inflammatory progressive loss of
endothelium that results in reduction of vision.

37. Inheritance-
• Most are sporadic
• Occasional AD inheritance
• Mutation in COL8A2 genealso identified
Female preponderance 4: 1
Elderly onset >50 years

38. SYMPTOMS
• Initially asymptomatic
• Gradual worsening of vision in the
morning, spontaneous improvement
during the day
• Glare
• Halos
• Recurrent foreign body sensation
• Pain due to rupture of bullae

39. SIGNS Slitlamp
examination-
• Corneal guttata-
irregular warts or
excresences seen in
the DM
• DM folds
• Stromal edema
• Microcystic epithelial
edema

40. Guttata seen on
PAS stain
Guttata on specular
reflection

41. –The guttata increase, enlarge
and coalesce and may fuse
with adjacent guttata
disrupting normal
endothelial integrity
known as beaten metal
appearance

42. • Endothelial decompensation
leading to stromal edema
• Epithelial microcysts
• Bullae
• Bullous keratopathy

43. COURSE OF DISEASE
• First phase- Asymptomatic with corneal guttata and fine
pigment dusting in the posterior corneal surface,advanced
cases‘beaten metal’.
• Second phase- Corneal edema, Pt experiences glare
and hazy vision. Edema progresses to epithelial
bullae, rupture of these cause severe pain
• Third phase- DM thickening and corneal thickness
upto 1 mm with bullous keratopathy
• Fourth phase- Growth of subepithelial connective tissue ,
decrease in corneal sensations, peripheral
neovascularisation+,

44. TREATMENT
1. Conservative management with topical Hypertonic
solution sodium chloride 5 % or 6%
2. Reduction of IOP
3. Corneal dehydration with hair dryer
4. Ruptured bullae - Bandage Contact lens ,
cycloplegics, antibiotics and lubricant drops,
Anterior stromal puncture maybe helpful

45. • When vision is severely affected posterior lamellar
keratoplasty (DSEK,DSAEK,DMEK) can be done
• Full thickness KP when Fuchs has advanced and whole
cornea is affected
• In eyes with poor visual potential conjunctival flap and
amniotic membrane transplantation
• New treatment method of using topical Rho-kinase inhibitor
with prior trans corneal endothelial cryotherapy , stimulates
the endothelial cell proliferation and improve function.

46. – When associated with cataract- Dilemma arises
whether cataract sx alone can improve vision or
whether cataract sx combined with KP
– The any one of the following indicators if +, combined
procedure should be done- triple procedure of
combined cataract extraction + lens implantation+
keratoplasty
1. The presence of microcystic edema
2. Stromal thickening ( CCT> 640 microns)
3. Low endothelial cell count ( < 1000 cell/mm²)

47. CORNEAL
GUTTAE

49. HISTOPATHOLOGY

50. REC
AP

51. THANK YOU! 