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
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
7.
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
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 +
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.
19.
20.
21.
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
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.
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.
31.
32.
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.
34.
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
41. –The guttata increase, enlarge
and coalesce and may fuse
with adjacent guttata
disrupting normal
endothelial integrity
known as beaten metal
appearance
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)