This document discusses various treatment options for managing keratoconus, including glasses, hard contact lenses, corneal collagen cross-linking (CXL), intracorneal ring segments, and keratoplasty. It provides details on the types of intracorneal rings (e.g. kerarings and myoring) and guidelines for when each treatment option is most appropriate based on the severity and progression of the condition, the patient's age, and corneal parameters. Key points emphasized are that keratoconus is a progressive disease, treatment requires customization for each patient, and the goal is to delay or avoid keratoplasty through stabilization and regularization of the cornea.
6. Clinical Picture
Patients with keratoconus (KC) often
report decreasing vision (distortions,
glare/flare, and monocular diplopia or
ghost images), with multiple
unsatisfactory attempts in obtaining
optimum spectacle correction
7. Signs
-Decrease in visual acuity
-Progressive myobia ,irrigular
Astigmatism
-Oil droplet sign by direct
ophthalmoscope - irregular
scissoring by retinoscopy
21. Topographical Patterns
Krumeich Classification of
Keratoconus:
Severity of KC is also classified by Krumeich.
This classification depends on mean K-
readings on the anterior curvature sagittal
map, thickness at the thinnest location, and
the refractive error of the patient.
22.
23. Forme Fruste Keratoconus
Forme Fruste Keratoconus (FFKC(:
is a subclinical disease and is not a
variant of KC. Although clinicians use
many other terms such as mild KC,
early KC, and subclinical KC
24. Recently, there are two opinions
regarding the definition of this disease:
1.FFKC is a completely normal cornea
with neither clinical nor topographical
risk factors, but this cornea is able to
develop KC when treated by laser.
The fellow eye may be keratoconic or
there may be a family history of KC
25. 2.FFKC is an abnormal cornea. Corneal
topography or corneal hysteresis or
both are abnormal; i.e., there are risk
factors but the case is still not a
clinically obvious KC.
30. Pellucid Marginal Degeneration (PMD)
and Pellucid-like Keratoconus
-PMD is a bilateral, non-inflammatory,
peripheral corneal thinning disorder
characterized by a peripheral band of
thinning of the inferior cornea. The
cornea in and adjacent to the thinned
area is ectatic.
-Patients usually are aged 20–40 years
at the time of clinical presentation.
36. Rules in treatment
1-Non of treatment options is satisfactory for the
patient.
2-The disease is progressive by its nature.
3-Follow up is mandatory.
4-Combination of treatment options can be done.
5-Keratoplasty can be a final destiny even with
treatment.
6-Rings mostly will be followed by glasses.
7-Don't judge on improvement of VA without correction.
6-Financial aspect should be taken into consideration.
37. Glasses and follow up
When?????
1-Age > 28 ys old.
2-Stable and low refraction with BCVA
>6/24
3-Clear cornea
4-Favorable Pentacam:
1(Average Keratometry <46 Ds
2(Thinnest Pachymetry > 480 um
38. Hard Contact Lens
--GP lenses are not the same as the
old hard lenses. For one thing, GP
lens materials allow oxygen to pass
through the lens and reach the
cornea.
-With advances in manufacturing, GP
lenses are made in thinner designs,
larger diameters, and with more
consistently smooth edges than ever
before.
39. -GP contact lenses are custom made for
each individual.
-Parameters which are needed for GP
contact lens request.
1(Keratometry: for initial fitting
2(Refraction.
40.
41. -Soft lenses do provide better initial comfort,
while GP lenses require a brief adaptation
period. But this is due to the size of the
lens — not the lens material.
-Soft lenses are larger in diameter than GP
lenses and "tuck under" the eyelids. As a
result, you don't feel the lens edges when
you blink. But since GP lenses are smaller,
during blinking your eyelids will experience
initial "lens awareness.
42. Hybrid lenses
This is a lens design combination that
has an RGP center surrounded by a
soft peripheral “skirt”. Hybrid contact
can provide the crisp optics of a GP
lens and wearing comfort of soft
contact lenses. They are available in
a wide variety of parameters to
provide a fit that conforms well to the
irregular shape of a keratoconic eye.
45. Why CXL is important???
-The only actual therapy for
keratoconus.
-Main effect is stiffening and flattening.
-Long term effect.
-Minimal optical effect.
63. When to do???
With Myoring:
-It should be done in the same session
( intrapocket CXL(.
-Epi-off like effect as it crosses the epithelium
With Kerarings:
-It should be done in the same session or after
ring implantation not before.
65. Young age < 25 ys ---------- be
more aggressive
Early Keratoconus: Epi-off CXL
stabilization and follow up
Moderate and severe Keratoconus:
CXL stabilization + Rings
Regularization and Flattening
Advanced opacified cornea :
Keratoplasty
66. Middle age > 25 ys ---------- be less
aggressive
Early Keratoconus: Epi-on CXL or follow
up
Moderate and severe Keratoconus:
Rings Regularization and Flattening with
follow up if progression Stabilization by
CXL
Advanced opacified cornea :
Keratoplasty
68. Aim:
-To delay corneal grafting.
-To make the eye refractable.
-To decrease coma aberrations.
N.B: Keratoplasty is still an option
69.
70.
71. Home message
-Many guidelines affect our decision in
keratoconus management.
-Pentacam is an important tool in evaluation
of Keratoconus patient.
-Age is a guiding factor in treatment with
aggressive attitude in young age.
-Customization should be done for every
patient in keratoconus management.