Keratoconus

KERATOCONUS

1. Dr. Christina

2. Progressive disorder in which the cornea
assumes a conical shape secondary to corneal
thinning and protrusion
Onset is around puberty- progresses untill 3
rd

or 4
th
decades of life
Both eyes affected usually
Role of hereditary transmission is not clear.

3. PRESENTATION
Presents usually during puberty.
Impairment of vision due to progressive
myopia and irregular astigmatism.
Asymmetrical nature.
Approximately 50% of normal fellow eyes will
progress to keratoconus within16 years.

5. DIAGNOSIS
Central or paracentral stromal thinning,
apical protrusion and irregular astigmatism
SIGNS:
Direct ophthalmoscopy shows ‘oil droplet
sign’.
Retinoscopy shows irregular’ scissor’ reflex’
Slit lamp microscopy showsfine, vertical,
deep stromal striae called vogts striae .

6. Epithelial iron deposits may surround the
base of cone –’fleischer ring’.
Marked irregular myopic astigmatism with
steep keratometry reading.
Bulging of the lower lid in down gaze-
‘munson sign’.
Corneal topography – sensitive method of
detecting early keratoconus.

7. ACUTE HYDOPS
Caused by rupture of descemets membrane
that allows influx of aqueous into the conea.
Causes sudden drop in visual acuity with
discomfort and watering.
Usually the break heals within 6-10 weeks and
edema clears but scarring results
Treatment is keratoplasty after edema
resolves.

9. ASSOCIATIONS
SYSTEMIC DISORDERS LIKE Down, Turner,
Ehler-Danlos and Marfan syndromes, atopy,
oesteogenesis imperfecta, MVP, mental
retardation.
OCULAR DISORDERS like vernal kerato
conjunctivitis, blue sclera, aniridia, ectopia
lentis, RP

10. TREATMENT
Spectacles in early stages.
Rigid contact lenses for higher degrees of
irregular astigmatism..Piggy back lenses.
Keratoplasty : both lamellar and penetrating
keratoplasty especially in cases of severe
corneal scarring.

11. THANK YOU