Keratoconnus

1. KERATOCONUS

2. DEFINITION
• Usually Bilateral,Non inflammatory
progressive ectasia of cornea resulting in
irregular myopic astigmatism
• Common in Hot and Dry climate
• Family history is usually negative from
patients but survey shows evidence of
genetics

4. CAUSES
• Exact cause: UNKNOWN!
• Extensive eye rubbing
• Inheritance
• Improper fitting/ extended CL wear
• Certain allergic disorders
• Overexposure to UV rays

5. • Keratoconus (from Greek: kerat
o- horn, cornea;
and konos cone) is
a degenerative disorder of
the eye in which structural
changes within the corneacause
it to thin and change to a
more conical shape than its
normal gradual curve.

7. DIAGNOSIS
• History taking
• Chief complaints
• Symptoms and signs
• Topometric reports

8. SYMPTOMS
• Blurred or distorted vision
• Frequent change of glasses
• Ghosting/monocular diplopia
• Haloes around light
• Glaring problem mainly night

9. SIGNS
EARLY LATE
Scissoring retinoscopic reflex
Irregular astigmatism
Distorted keratometric mires
Cone formation
Corneal thinning
Advanced cone formation
Non uniform red reflex in
ophthalmoscopy
Munsons sign
Slit lamp findings:
Vogts line
Fleishers ring
Scarring in corneal epithelium

10. SCISSORING REFLEX

11. Distorted keratometric mires

12. Munsons sign

13. Vogt’s Line

14. Flieshers ring

16. COLLAGEN CROSS LINKING
• It is a method for stopping progression of KC
• Involves a one-time application
of riboflavin solution(Vitamin drop) to the eye
that is activated by illumination with UV-A light
for approximately 30 minutes.
• The riboflavin causes new bonds to form across
adjacent collagen strands in the stromal layer of
the cornea, which recovers and preserves some
of the cornea's mechanical strength.
• The corneal epithelial layer is generally removed
to increase penetration of the riboflavin into the
stroma.

19. C3R

20. LENSES
• Glasses or soft contact lenses:Early keratoconus can be treated
with glasses or soft contact lenses to correct blurry or distorted
vision. But because the condition is progressive, most people find
they frequently need to change the prescription of their lenses as
their corneas' shape changes.
• Rigid gas permeable contact lenses: Hard contact lenses are often
the next step in treating progressing keratoconus. Rigid lenses may
feel uncomfortable at first, but they will feel better later mainly
with vision
• Hybrid lenses:For people who can't tolerate hard contact lenses,
these contacts have a rigid center with a softer ring around the
outside for increased comfort
• Piggyback: RGP on soft CL.
• Customized contact lenses :These rigid gas permeable lenses are
custom created for each individual based on topographical
measurements of cornea: ROSE K lens
• Scleral contact lenses These lenses are useful for irregular cornea
changes, because they rest on sclera and vault over the cornea,
instead of resting on the cornea like traditional lenses.

24. INTACS

25. Deep Anterior Lamellar Keratoplasty
(DALK)
• Surgical procedure for removing the corneal
stroma down to Descemet’s membrane
• Host corneal endothelium is retained, and
anterior corneal tissue is replaced with normal
thickness donor tissue.
• As the host
endothelium is retained there is no risk of
rejection, and steroids have to be
given only for a short duration of time

28. REMEMBER!
• Make patient clearly understand about KC and
its progressiveness
• Objective refraction may not work due to
scissoring,make a good subjective refraction.
• While giving Glass explain patient that change
may occur in power frequently.
• Followup very important
• Depending on stage of KC advice proper
treatment