Disciform Keratitis

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Disciform Keratitis
Clinical
Definition
Disciform keratitis is a stromal deep keratitis
with disc – like oedema. Exact etiology is
unknown. This condition is mainly caused by
herpes virus (and sometimes due to vaccinia
and herpes zoster virus).
Pathogenesis
A delayed type of hyper sensitivity reaction
to HSV – antigen. Low grade stromal
inflammation with damage to the underlying
endothelium passage of aqueous into the
corneal stroma.
Clinical features
1. In mild form only central zone of
focal disc – shaped stromal oedema
with surrounding epithelid edema &
fine KPS. There is no necrosis or no
neovascularisation.
2. In severe form
a. stromal oedema is more diffuse
b. presence of descemet’s folds
c. deep vascularisation
d. focal bullous keratopathy
e. marked anterior uveitis
f. absence of or diminished corneal
sensation. Healed lesions may have
ring of stromal (or) sub epithelial
opacification & thinning
• Topical corticosteroid drops (4-5 times
daily) under anti – viral cover (acyclovir
ointment 2-5 times daily) are given.
• The use of diluted steroid drops reduces
the incidence of any steroid – related
complication
• Cycloplegics like atropine eye ointment
• In majority of the cases, it resolves over a
period of several weeks.
Acanthamoeba Keratitis
Definition – Pathogenic
Acanthamoeba is a free living protozoon. It
is found in stagnant water (pond, swimming
pool, bath tub etc) and contact lens cases.
Cystic form turns into trophozoites in
appropriate condition which produce
enzymes leading to tissue penetration 4
destruction.
Modes of infection
• Contact lens wearer – via contaminated
solution
Treatment
• The first aim is to heal any associated
epithelial lesion.
KPS - Keratic precipitates; Necrosis - death of cells; Stagnant - motionless
A R A V I N D
E Y E
C A R E
S Y S T E M
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• Non – contact lens wearer – direct
contamination after a minor trauma
Clinical Features
• Frequently misdiagnosed as herpetic or
fungal keratitis for many weeks
• Severe pain and it is out of proportion
to the degree of inflammation (radial
keratoneuritis)
• Defective vision
• Progressive chronic stromal keratitis
with recurrent break down of corneal
epithelium
• Frequent development of paracentral
ring – shaped ulcer or abscess which may
perforate.
• Nodular scleritis is frequently found.
Slowly progressive stromal opacification
and vascularization occur.
• It may be associated with limbal
inflammation (limbitis).
• It does not respond to conventional
antimicrobial treatment
Diagnosis
Corneal scrapings calcofluor white staining
for amoebic cyst.
Treatment
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•
•
•
Culture of contact lenses
PCR, invivo confocal microscopy
Debridement of infected epithelium
In resistant cases a therapeutic penetrating
keratoplasty may be required.
• Neomycin drops and ointment
- Ms. M.Sasikala,
Refraction – T.Kallupatti VC
Debridement - Removal of damaged tissue; Contaminate - make something impure
Compassion Apr - June, 2015