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~ Kunjvihari Yadav
(Optometry intern at UPUMS, Saifai, Etawah, UP)
Introduction
 From Greek
Kerato= Cornea
Conus = Cone-shape
 Definition - keratoconus is a degenerative non-inflammatory
disease of the cornea where the central or paracentral cornea
undergoes progressive thinning , changing it from dome-shaped to
cone shape , causing irregular astigmatism.
Keratoconus & it’s management (kunj).pptx
Onset of keratoconus
 It can be anywhere between the ages of 8 and 45.
 In the majority, it becomes apparent between the ages of 16 and 30
years .
 It affects male and female equally .
 KC is present in both eyes in over 90% of cases.
 Onset is not always at the same time or to the same magnitude .
 KC is has been associated with conditions such as-
• Hay fever
• Asthma
• Eczema
• Down’s syndrome
• Marfan’s syndrome etc.
Etiology
 Still unknown.
 The incidence of KC reported to be 1 in 2000 people
 Heredity- there is less than one in ten chances that a blood relative
of keratoconic patient will have KC.
 Eye rubbing- especially children due to some diseases as vernal
keratoconjunctivitis . So corneal curvature will be changed . Eye
rubbing among keratoconic patient has been reported 66% to 73% .
 Hormonal change - that KC is often first develops around puberty.
Or advances during pregnancy.
 Contact lens wearer- uncorrect fitting.
Classifications
 Based on severity of curvature -
• Mild: <45.00D
• Moderate: 45.00D to 52.00D
• Advanced: 52.00D to 62.00D
• Severe: >62.00D
 Based on shape -
• Nipple cones: cone small size 5mm
• Oval cones: larger ellipsoid 5-6mm
• Globus cones: largest>6mm, may involve over 75% of
cornea
Nipple cone Oval cone Globus cone
• Diameter: <5mm
• Cone: lies in centre towards
inferior nasal quadrant
• Easiest to fit with CL
• Diameter: >5mm
• Cone: displaced
inferiorly
• More difficult to fit
with CL
• Diameter: >6mm
• Cone: steepening
• 75% affected cornea
• Most difficult to fit with CL
Keratoconus & it’s management (kunj).pptx
The classic signs of KC
Corneal nerves:
• More prominent then in
normal eye.
Vogt’s striae:
• Fine vertical line in the
stroma and Descemet’s
membrane.
• disappear temporarily on
digital pressure.
Fleischer’s ring:
• Iron pigment ring forms
the base.
• May be partial or
complete.
The classic signs of KC
Corneal thinning:
• Represents an actual
reduction in the number
of stromal lamellae.
Munson’s sign:
• Ectasic protrusion of the
cornea on down gaze
produces a V-shaped
conformation of the lower
lid.
Rizzuti sign:
• Lateral illumination of the
cornea produces a steeply
focused beam of light near
the limbus.
Corneal scarring:
• Sub-epithelial corneal scarring.
• Not generally seen early.
• May occurs as keratoconus
progresses because of ruptures in
bowman’s membrane which is then
filled with connective tissue.
Corneal hydrops:
• Occurs generally in advanced cases,
when Descemet’s membrane
rupture, aqueous flows into the
cornea and reseals.
Diagnosis
 Diagnosing keratoconus in its early
stages is more difficult . It requires a
through history and examination .
• Visual acuity – Reduced visual acuity
due to oblique astigmatism.
• Retinoscopy – scissor reflex
• Keratometer- distorted mires
• Ophthalmoscopy – oil droplet
• Reduced intraocular pressure- due to
corneal thinning or reduced scleral
rigidity.
• The topography of keratoconus – the photokeratoscope or placido
disc can provide an overview of the cornea and can show the
relative steepness of the corneal area.
 Photokeratoscope with normal round curvature  Distorted pattern of the rings.
Nipple-Shaped Topography
Small near central ectasia, less than
5.0 mm in cord diameter .
May manifest as a small central ectasia
with moderate to high with-the-rule
corneal astigmatism.
Oval-Shaped Topography
Globus-Shaped Topography
Management of kc
 Spectacles-
• Mild keratoconus in early stage
can be corrected with spectacles.
• As the cornea steepens and
becomes more irregular , glasses
not capable of providing adequate
visual improvement.
 Contact lenses -
• Soft contact lenses.
• Rigid gas permeable lenses.
• Combined lens system-
1. Piggy back system
2. Hybrid lens system
• Fully keratonic designed lenses-
1. Rose k
2. Scleral and mini scleral lens
 soft contact Lenses -
• It is not better than spectacle lens but it works in piggy back system
.
• At very stage, this way work as equal to spectacle .
• But patient may not be satisfied with the level of vision he has even
though it is 6/6-
• Shadow effect of texts
• Ghosting of image
• Poor night vision
• Eye fatigue on prolong reading
 Rigid Gas Permeable Lenses -
• Cost effective , easily available ,
suitable for mild to moderate
keratoconus .
• Fitting: three point conventional
fitting philosophy.
 combined lens system -
 Piggy back system-
Rigid lens fitted over a hydrogel lens
increases comfort resulting in
adequate wearing time with good
vision .
 combined lens system -
 hybrid lens system –
One way to overcome the problems with piggyback lenses, yet have
the optics of a rigid lens with the comfort of a hydrogel , it is to fuse a
soft rim onto a hard central portion .
fully keratoconic designed lens -
• Rose K: • Scleral lenses
 Surgical intervention-
 Collagen cross-
linking (CXL or C3-
R):
It may slow or halt the
progression of
keratoconus by using a
photo-oxidative treatment
to increase the rigidity of
the corneal stroma .
 Keratoplasty
• For patients intolerant to contact lens and cases with scarring.
• Penetrating keratoplasty and Deep anterior lamellar keratoplasty can
be done .
Penetrating keratoplasty:
In this procedure , the central area
of the cornea is excised and a full-
thickness corneal button is sutured
into the recipient
 Lamellar keratoplasty:
A partial thickness portion of the cornea is excised and a partial
thickness donor corneal button is sutured into the recipient
transplant .
 Intacs: intrastromal corneal ring –
Two arc shaped segments of inert plastic are inserted into the
peripheral (outer) cornea.
These segments add volume to the thinned area .
This flattens the steep curvature and reduces the irregular shape.
STEPS IN KERATOCONUS TREATMENT
KERATOCONUS
PROGRESSIV
E
NON PROGRESSIVE
SPECTACLE
S
CONTACT
LENSES
CXL
CORNEAL SCLERAL
INTACT
S
CORNEAL
TRASPLANT
S
PHAKIC
IOLS
ACCELARAT
ED CXL
SURGICAL
OPTIONS
SCLERAL LENSES ARE THE BEST CHOICE FOR KERATOCONUS
Keratoconus & it’s management (kunj).pptx

More Related Content

Keratoconus & it’s management (kunj).pptx

  • 1. ~ Kunjvihari Yadav (Optometry intern at UPUMS, Saifai, Etawah, UP)
  • 2. Introduction  From Greek Kerato= Cornea Conus = Cone-shape  Definition - keratoconus is a degenerative non-inflammatory disease of the cornea where the central or paracentral cornea undergoes progressive thinning , changing it from dome-shaped to cone shape , causing irregular astigmatism.
  • 4. Onset of keratoconus  It can be anywhere between the ages of 8 and 45.  In the majority, it becomes apparent between the ages of 16 and 30 years .  It affects male and female equally .  KC is present in both eyes in over 90% of cases.  Onset is not always at the same time or to the same magnitude .  KC is has been associated with conditions such as- • Hay fever • Asthma • Eczema • Down’s syndrome • Marfan’s syndrome etc.
  • 5. Etiology  Still unknown.  The incidence of KC reported to be 1 in 2000 people  Heredity- there is less than one in ten chances that a blood relative of keratoconic patient will have KC.  Eye rubbing- especially children due to some diseases as vernal keratoconjunctivitis . So corneal curvature will be changed . Eye rubbing among keratoconic patient has been reported 66% to 73% .  Hormonal change - that KC is often first develops around puberty. Or advances during pregnancy.  Contact lens wearer- uncorrect fitting.
  • 6. Classifications  Based on severity of curvature - • Mild: <45.00D • Moderate: 45.00D to 52.00D • Advanced: 52.00D to 62.00D • Severe: >62.00D  Based on shape - • Nipple cones: cone small size 5mm • Oval cones: larger ellipsoid 5-6mm • Globus cones: largest>6mm, may involve over 75% of cornea
  • 7. Nipple cone Oval cone Globus cone • Diameter: <5mm • Cone: lies in centre towards inferior nasal quadrant • Easiest to fit with CL • Diameter: >5mm • Cone: displaced inferiorly • More difficult to fit with CL • Diameter: >6mm • Cone: steepening • 75% affected cornea • Most difficult to fit with CL
  • 9. The classic signs of KC Corneal nerves: • More prominent then in normal eye. Vogt’s striae: • Fine vertical line in the stroma and Descemet’s membrane. • disappear temporarily on digital pressure. Fleischer’s ring: • Iron pigment ring forms the base. • May be partial or complete.
  • 10. The classic signs of KC Corneal thinning: • Represents an actual reduction in the number of stromal lamellae. Munson’s sign: • Ectasic protrusion of the cornea on down gaze produces a V-shaped conformation of the lower lid. Rizzuti sign: • Lateral illumination of the cornea produces a steeply focused beam of light near the limbus.
  • 11. Corneal scarring: • Sub-epithelial corneal scarring. • Not generally seen early. • May occurs as keratoconus progresses because of ruptures in bowman’s membrane which is then filled with connective tissue. Corneal hydrops: • Occurs generally in advanced cases, when Descemet’s membrane rupture, aqueous flows into the cornea and reseals.
  • 12. Diagnosis  Diagnosing keratoconus in its early stages is more difficult . It requires a through history and examination . • Visual acuity – Reduced visual acuity due to oblique astigmatism. • Retinoscopy – scissor reflex • Keratometer- distorted mires • Ophthalmoscopy – oil droplet • Reduced intraocular pressure- due to corneal thinning or reduced scleral rigidity.
  • 13. • The topography of keratoconus – the photokeratoscope or placido disc can provide an overview of the cornea and can show the relative steepness of the corneal area.  Photokeratoscope with normal round curvature  Distorted pattern of the rings.
  • 14. Nipple-Shaped Topography Small near central ectasia, less than 5.0 mm in cord diameter . May manifest as a small central ectasia with moderate to high with-the-rule corneal astigmatism.
  • 17. Management of kc  Spectacles- • Mild keratoconus in early stage can be corrected with spectacles. • As the cornea steepens and becomes more irregular , glasses not capable of providing adequate visual improvement.
  • 18.  Contact lenses - • Soft contact lenses. • Rigid gas permeable lenses. • Combined lens system- 1. Piggy back system 2. Hybrid lens system • Fully keratonic designed lenses- 1. Rose k 2. Scleral and mini scleral lens
  • 19.  soft contact Lenses - • It is not better than spectacle lens but it works in piggy back system . • At very stage, this way work as equal to spectacle . • But patient may not be satisfied with the level of vision he has even though it is 6/6- • Shadow effect of texts • Ghosting of image • Poor night vision • Eye fatigue on prolong reading
  • 20.  Rigid Gas Permeable Lenses - • Cost effective , easily available , suitable for mild to moderate keratoconus . • Fitting: three point conventional fitting philosophy.
  • 21.  combined lens system -  Piggy back system- Rigid lens fitted over a hydrogel lens increases comfort resulting in adequate wearing time with good vision .
  • 22.  combined lens system -  hybrid lens system – One way to overcome the problems with piggyback lenses, yet have the optics of a rigid lens with the comfort of a hydrogel , it is to fuse a soft rim onto a hard central portion .
  • 23. fully keratoconic designed lens - • Rose K: • Scleral lenses
  • 24.  Surgical intervention-  Collagen cross- linking (CXL or C3- R): It may slow or halt the progression of keratoconus by using a photo-oxidative treatment to increase the rigidity of the corneal stroma .
  • 25.  Keratoplasty • For patients intolerant to contact lens and cases with scarring. • Penetrating keratoplasty and Deep anterior lamellar keratoplasty can be done . Penetrating keratoplasty: In this procedure , the central area of the cornea is excised and a full- thickness corneal button is sutured into the recipient
  • 26.  Lamellar keratoplasty: A partial thickness portion of the cornea is excised and a partial thickness donor corneal button is sutured into the recipient transplant .
  • 27.  Intacs: intrastromal corneal ring – Two arc shaped segments of inert plastic are inserted into the peripheral (outer) cornea. These segments add volume to the thinned area . This flattens the steep curvature and reduces the irregular shape.
  • 28. STEPS IN KERATOCONUS TREATMENT KERATOCONUS PROGRESSIV E NON PROGRESSIVE SPECTACLE S CONTACT LENSES CXL CORNEAL SCLERAL INTACT S CORNEAL TRASPLANT S PHAKIC IOLS ACCELARAT ED CXL SURGICAL OPTIONS SCLERAL LENSES ARE THE BEST CHOICE FOR KERATOCONUS