Fleischer's ring (arrowed) around the cone Vogt's striae
Enlarged corneal nerves Corneal scar from previous hydrops
Thinning of the corneal apex with striation of the
stroma and descemet's membrane (Vogt's striaes).
There is Fleischer's ring surronding the cone (blue light
on the slit-lamp can improve its visualization).
Corneal nerves are prominent.
Corneal scars from previous hydrops.
Examine the fellow eye which may show a different
stage of progression or corneal graft
Munson's sign (distortion of the lower lid on down-
Rizzuti's sign (conical reflection on the nasal cornea
when a penlight is shone from the temporal side).
Down's syndrome, atopic eczema, connective tissue
disorders (Marfan's syndrome)
Acute hydrops develops from a break in
the descemet's membrane leading to the
entry of aqueous into the stroma causing
stromal edema. The condition is painful
and the cornea appears opaque.
It is not an indication for urgent corneal
graft because the edema tends to resolve
over weeks and months when the
endothelium cells enlarge and grow over
the descemet's break.
Cycloplegic and topical steroid are often
used because of the pain and
photophobia. Sodium chloride 5% can be
used to reduce the edema.
There is fragmentation of Bowman's layer
Thinning of the stroma and overlying
The descemet's membrane shows folds
Diffuse scarring is often present in the
The main problem is high astimgatism
which is irregular and often progressive.
Glasses can initially correct the
astigmatism and when these become
ineffective hard contact lens is used.
When the vision can not be corrected
with the contact lens or when the cornea
becomes too steep for the contact lens,
corneal graft is indicated.
The topography shows the typical
inferior steepening of the cornea.
Pellucid marginal degeneration
The topography shows inferior
steepening of the cornea, but also
shows the typical flattening of the
There are multiple horizontal lines in the descemet's
membrane (Haab's striae).
The cornea may be edematous if there are insufficient
Look for secondary congenital glaucoma such as
aniridia, anterior chamber cleavage syndrome.
Measure the corneal diameter (the normal corneal
diameter is between 10 and 12 mm) with the slit-lamp.
Check the corneal edge on the temporal side for
any goniotomy scars.
Also look for trabeculectomy scar at the superior
Examine the optic disc for glaucomatous
Check the patient's glasses, the affected side
invariably has a myopic prescription.
There is a band of sub-epithlial whitish depositions in the inter-palpebral
zone. It is separated from the limbus by a clear zone. There are multiple
round clear holes (due to nerve channels).
Look for any coexisting corneal lesions
such as interstitial keratitis
If the patient is young (especially female)
look for pseudophakia and aqueous haze
and signs of arthritis
A unilateral band keratopathy may be
caused by a phthisical eye
If the center of the band is clear with
well-defined edges, the calcium may
have been removed with EDTA
or excimer laser.
The cornea has diffused stromal haze.
High magnification shows ghost (empty) vessels in the deep and
The cornea may be thin. The condition is usually bilateral.
Signs of congenital syphilis
It occurs in congenital syphilis and
usually develops in the first or second
decades of life.
It is divided into three stages:
Early stage: characterized by ocular pain,
photophobia. There is deep stromal and
endothelial edema. KPs may occur.
Florid stage: when the inflammation is at its
peak with iridocyclitis. There is deep stromal
vessels which gives a pink color to the cornea
Regression: vascular regression with clearing
of the stromal infiltrates leaving behind
corneal scarring. This may take up to 1 or 2
years to resolve unless topical steroid is used.
Corneal deposits (basal layer of the epithelium) distributed in whorl's-like pattern
Look for signs of:
Amiodarone intake (for example photosensitivity of
the skin, irregular pulse rate). There may be BRAO or
CRAO from emboli)
Indomethacin intake (look for signs of rheumatoid
Fabry's disease (renal failure with arterio-venous
fistula, angiokeratomas, dilated and tortuous
conjunctival vessels with or without aneurysms)
It is an X-linked disorder due to a
deficiency of alpha-galactosidase.
It causes deposition of glycosphingolipid
in the body tissue.
Renal involvement causes renal failure.
Skin lesion termed angiokeratoma
corporis discusum consists of clusters of
superficial cutaneous dark-red
Apart from vortex keratopathy, there
may be tortuosity and aneurysmal
dilatations of the conjunctival and retinal
There are multiple sub-epithelial ring-shaped opacities (so called
honeycomb appearance) in the center of the cornea
Opacities may extend towards the periphery in severe cases. The corneal
surface is irregular with ferritin deposition.
Look at the opposite eye for: Similar changes, corneal graft
Appear in the first few years of life and mainly
affects the Bowman's membrane
Symptoms begin in the first or second decade
with painful, recurrent epithelial erosion.
Vision is affected by both anterior scarring with
surface irregularity and anterior stromal oedema
(from recurrent corneal erosion)
Histologically, there is disruption and absence of
Bowman's layer, with replacement by fibrocellular tissue
that corresponds clinically to areas of subepithelial
Keratoplasty is the treatment of choice (either
penetrating or lamellar) and recurrence in the
graft is common.
There are refractile, branching lines (in the stroma) The periphery of the cornea is
spared. The lines may be double contoured in advanced cases.
Has the highest tendency for recurrence in the graft.
Look for systemic amyloidosis (rare) such as macroglossia and periorbital papules
Classic type, type AA amyloid
No systemic amyloid deposition
Lattice dystrophy with coexistent systemic amyloidosis
lines are less numerous and located more peripherally
Known as Meretoja's syndrome. The patient may have
cranial and peripheral neuropathy.
Mid-stromal and larger deposit than those in type I
Deposits are of type AP amyloid
The cornea is stained with Congo red,
and contains multiple reddish deposits representing amyloid deposits.
There are multiple greyish white opacities involving the stroma and the corneal
periphery (in granular and lattice dystrophy, the periphery is typically spared). The stroma
between the opacities is diffusely cloudy
Right picture: recipient cornea showing changes of macular dystrophy
(because the dystrophy extends to the periphery).
It is a autosomal recessive condition
Characterized by an accumulation of
glycosaminoglycan both intra and
It is thought to be caused by defective
It is thought to be a type of localized
It is an inborn error of metabolism
characterized by glycosaminoglycan
The condition is usually autosomal
recessive except for Hunter's Syndrome
which is X-linked.
Most of these patients have ocular
involvement which include corneal
cloudiness, retinal pigmentary
degeneration and optic atrophy.
Most patients develop significant visual
impairment by the age of 30
Corneal graft is usually necessary to
Recurrence has been reported in grafted
cornea and re-graft is sometimes
Macular dystrophy is best shown with alcian blue and colloidal iron.
Colloidal iron is used in this case.
There are multiple small, well-demarcated, grayish white opacities(in the anterior
The intervening stroma is clear and the peripheral cornea is not involved.
Classically described ‘bread crumbs’, some have crystalline like appearance
The opposite eye either has similar changes or has corneal graft
It is an autosomal dominant condition.
It usually presents in the teens with
photophobia or abnormal corneal
Recurrent erosion is uncommon.
Vision is often normal or only become
impaired in the 40s.
Full thickness graft is sometimes needed
but recurrence is unusual.
The cornea has been stained with Masson trichrome which shows up the
granular dystrophy as red
There are multiple
small white crystals
in the center of the
cornea (just below
The surface of the
cornea is uninvolved
and there may be
Schnyder central crystalline
There are multiple
separated by crack
like clear zones
resemble crocodile shagreen)
The opacities are
denser in the
center and the
posterior aspect of
Central cloudy dystrophy of
There are multiple
vesicles in the
endothelium. There are
also multiple greyish
opacities which may be
curvilinear or has
In some patients there may
be stromal oedema or
abnormal iris shape such as
or irido-corneal adhesion
(the changes may resemble
ICE syndrome but the
condition is bilateral)
There are multiple
opacities in the
epithelium and has
They can all present with endothelial failure with
Fuchs' endothelial dystrophy: autosomal
dominant; usually present in the 5th-6th decade
with corneal edema
Posterior polymorphous dystrophy: autosomal
dominant; most patients are asymptomatic but
in some there may be corneal edema. The
trabecular meshwork and the iris may be
involved by the abnormal endothelium giving
rise to glaucoma and abnormal iris shapes
Congenital hereditary endothelial dystrophy:
may be autosomal dominant or recessive. The
recessive form is associated with severe corneal
edema at birth.
There are radial incisions (usually four or eight) in the cornea with a clear central
zone. There may be ferritin lines at or around the incisions.
Radial incisions (up to a depth of 90%)
causes flattening of the cornea and
reduces the radius of curvature of the
cornea. This procedure weakens the cornea and
trauma to the eye can easily cause.
The amount of correction (i.e. the
refractive effect) is determined by the
depth, length and number of cuts.
Typical facial feature in acne rosacea Cornea neovascularization in
The face is red with telangiectasia, papules and pustules found mainly on the
nose, cheeks and chin. The nose may have irregular thickening of the skin with
large follicular orifices (rhinophyma).
Look for: Blepharitis, meibomian gland dysfunction, keratitis.
Acne rosacea is a common skin condition of
Ocular involvement is common but most tend to
Ocular problems is more severe in males
Eyelids show blepharo-conjunctivitis sometimes
with thick meibomian secretion (chalazion may
There may be scars on the tarsal conjunctiva
suggesting previous recurrent chalazion.
The cornea show pannus with or without
peripheral corneal thinning.
There are subepithelial opacities especially
The lid problems include blepharitis and chronic
Lid hygiene and hot compresses are needed to keep the
In severe cases, oral doxycycline is useful for a period
of 6 weeks but some patients may need the treatment
for much longer.
The cornea problems are related to dry eyes,
neovascularization and peripheral ulceration.
Dry eyes can be controlled with lid hygiene and artificial
Neovascularization results from chronic corneal
inflammation, and low dose steroid is useful but should
be used with care due to the risk of perforation.
Peripheral ulceration may result from Staphylococcal
hypersensitivity and the treatment involve lid hygiene
and low dose combination of steroid and antibiotic.
has the tendency for
binding to growing
structures that require
teeth and bones). These
can result in unsightly
staining of the teeth,
dental hypoplasia and
should be avoided in
pregnant women and
young children. It is also
contraindicated in breast
feeding women as the
drug is secreted in
A 3-month pregnant
severe blepharitis and
keratitis secondary to
How would you treat
A penetrating corneal graft
with interrupted sutures
A tectonic graft
performed for peripheral corneal
perforation resulting from rheumatoid
arthritis-related corneal melt
Penetrating or lamellar graft (look at the edge of
the graft for the thickness)
The sutures are interrupted / continuous or a
combination of both
Is the graft eccentric (it is likely to be tectonic)
Signs of rejection which may be:
Epithelial, stromal or endothelial.
Rejection lines on the endothelium are called
keratic precipitates, cells or flare in the anterior
Security of the suture and any pannus around
Presence of IOL especially anterior
chamber lens suggest pseudophakic
Look at the recipient cornea for signs for
corneal dystrophy (this is especially obvious with
macular dystrophy which extend to the peripheral cornea)
Examine the other eye for signs of
dystrophies or keratoconus.
In tectonic graft observe the patient's
hands for rheumatoid arthritis which may
be the cause of peripheral corneal melt
Problems related to surgery and sutures
Non-immune corneal problems
Resuturing, patching or contact lenses
Flat chamber/iris incarceration in the wound:
Poor integrity of the wound or high IOP
Early surgical intervention is important
Paracentesis and vitreous tap for culture and sensitivity
followed by intravitreous antibiotic with amikacin and
Tightening, loosening, infectious abscesses and
vascularization along suture tracks etc.
The sutures are removed and appropriate treatment
Primary endothelial failure:
From deficiency of donor endothelium or the cornea is
sutured with the endothelium side up by mistake.
Re-graft is the only option
Persistent epithelial defect:
This usually heal by 14 days.
Treat any dry eyes, exposure keratitis or trichiasis
Recurrence of primary disease:
Treat conditions such as herpes keratitis as appropriate
Intensive topical antibiotics are needed
Late non-immune endothelial failure:
Re-graft is needed
Post-operative corneal astigmatism:
Removal of the offending sutures and consider CL
Refractive surgery may be needed
Usually occurs after the first two weeks and
early recognition is important for good outcome
Endothelial rejection is the most serious.
Keratic precipitates and Khodadoust's lines may be
Patient should be admitted for intensive topical
May resemble adenoviral infection, may be directed at
the donor epithelium or keratocytes and may precede
more serious rejection
Topical steroid is the treatment of choice.
Donor epithelium may be rejected showing as a
As the host cells replace lost donor epithelium, this
rejection is less serious than endothelium rejection but
it may precede endothelium rejection.
The two main methods of storing are by Refrigeration
4°C (USA) in Organ culture at 31-37°C (Europe).
longer storage time
Greater opportunity to detect infection
Reduced risk of Post-op endophthalmitis
Eyes are first washed in several changes of sterile saline,
immersed in a dilute iodine solution, which is neutralized
with sodium thiosulphate, and then given a final wash in
The cornea with a 3-4mm rim of sclera is then carefully
excised taking care to avoid damage to the endothelium.
A suture is placed through the scleral rim and the cornea
is suspended in about 80-ml of tissue culture medium.
The corneas are then stored in an incubator.
After a week, a sample of medium is withdrawn to check
for bacterial and fungal infection. Up to 4% of corneas are
discarded for this reason.
The quality of the tissue is assessed, primarily by
examination of the endothelium to estimate endothelial
cell density and to detect endothelial damage or other
A minimum cell density of 2200 cells/mm2 with no central
stromal opacity is considered acceptable for penetrating
This quality assessment means that no age limits to
corneal donation need be set.
Because corneas become edematous and thickened during
organ culture, they are transferred to tissue culture
medium containing 5% dextran after assessment of the
endothelium. The osmotic effect of the dextran thins the
cornea and returns it towards normal thickness prior to
surgery. The corneas can remain in this medium for four
days by which time they would have been transported to
a recipient hospital and grafted.
Corneas are tested for????
• There is are peripheral
thinning of the superior
cornea which has a
sloping peripherally and a
sharp central edge
• Usually bilateral but
• The epithelium is intact
and contains superficial
• There may be pseudo-
pterygium in advanced
Although usually asymptomatic,
advanced cases may affect the vision by
causing astigmatism which is usually
against the rule.
There is also the risk of corneal
perforation with minor trauma
• There is thinning with
ulceration involving a
sector of the peripheral
• Look for:
• Associated systemic signs
such as symmetrical
arthropathy in rheumatoid
arthritis or saddle nose in
• Associated eye signs such
as keratoconjunctiva sicca
or scleromalacia perforan
both of which may occur in
Peripheral corneal ulceration
due to systemic diseases
• There is peripheral
ulcerative keratitis which
is contiguous with the
limbus without intervening
• The epithelium is
vascularized and there is
• The whole corneal
circumference may be
• The sclera is not involved.
The diagnosis is based on the clinical
history and characteristic appearance in
conjunction with the exclusion of other
causes of peripheral ulcerative keratitis.
There are no histological or blood tests
for its diagnosis.
There is a prominent
irregular ridge which lies
central to the limbus.
It is caused by an
displaced Schwalbe's line.
(junction of the TM with
the termination of
Note: this finding is seen in
about 8 to 30% of normal
Look for other pathology !
There is posterior
embryotoxon with iris strands
attached to it. Peripheral
anterior synechiae and
hypoplasia of the
anterior stroma may be seen.
Axenfeld's anomaly have
posterior embryotoxon plus
Reiger's anomaly have
anterior synechiae, iris atrophy
and pupil distortion
Reiger's syndrome is Reiger's
anomaly plus dental,
craniofacial and skeletal
Corectopia, ectopia uvea and
Abnormal denture and maxillary
Dental dysplasia in a patient with Axenfeld-Reiger's syndrome
There is central corneal
opacity involving the
stroma with iris adhesion
at the edges of the
Evidence of congenital
(if any of these were
present, the condition is
called Peters plus syndrome)
Posterior embryotoxon and Axenfeld-
Reiger's syndrome are usually inherited
in an autosomal dominant fashion.
Peters' anomaly may be sporadic,
recessive and sometimes dominant.
Posterior embryotoxon alone is not
associated with glaucoma.
50% of the patients with Axenfeld-
Reiger's syndrome and Peters' anomaly
will develop glaucoma.
U Ulcers (e.g. herpes simplex)
M Metabolic disorders (e.g. MPS)
P Peters' anomaly
E Endothelial dystrophy (e.g. CHED)