This presentation discuss all controversies and debates about keratoconus management trying to cover them in a simplified manner .

1. BY
Dr. Amr Mounir
Lecturer of ophthalmology
Sohag university

3. 
1- Unstable disease
2- Progressive
3- No treatment modality is sufficient
4- No treatment is satisfactory to the patient .
5- Needs to stabilize the disease and then optical
correction .
Why keratoconus management is still a problem
???

4. 
First : CXL
Second : ICR
Third : Toric ICL
Recent treatment
modalities

7. 
1- Epi.on or Epi.off
2- Haze after Crosslinking.
3- High Fluence CXL
Controversies

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10. 

11. 
CXL is done by riboflavin and UV.A to
crosslink the collagen bundles of the cornea.
Riboflavin cannot cross the intact corneal
epithelium so epithelium is removed to load
the stroma with it. In Epi.on CXL certain
formulas of riboflavin can penetrate intact
epithelium so epithelium removal isn't
needed
Epi.on……. is it effective
???

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13. 
Good anterior chamber flare

14. 
Good corneal soaking

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Epi.off has a lot of complications

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Complications of Epi.off CXL

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Complications of Epi.off CXL

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Complications of Epi.off CXL

25. 
Complications of Epi.off CXL

26. 

27. 
A 32 ys old male with keratoconus grade (1)
Subjected to Epi-on CXl ,
Preoperative refraction :
-5 Ds -5Dc @74 with BCVA : 6/48
From our short experience in Sohag
Future Center for Corneal surgeries

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Preoperative Pentacam

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33. 
-5 Ds -3Dc @ 72 with BCVA : 6/24
Avg K: Decrease by 2 Ds
Cylinder : Decrease by 2 Dc
Postoperative refraction

34. 
Although Epi-off CXL is still more
effective than Epi-on , However Epi-on
CXL is safer and effective CXL
technique which show very promising
results in management of Keratoconus
Conclusion

35. 
1- Stage 1 < or = 49 Ds
2- Clear cornea
3- BCVA > or = 6/12
Indications of CXL

36. 
1- Thinnest point < 360 um
2- Central corneal opacity
3- Age > 40 ys
4- Low compliance of the patient
Contraindications

37. 
Haze after CXL

38. 
 Haze after CXL is different in clinical character from
haze after other procedures, such as excimer laser
photorefractive keratotomy. The former is a dust-like
change in the corneal stroma or a midstromal
demarcation line, whereas the latter has a more
reticulated subepithelial appearance. Similarly, the
mechanisms leading to haze formation
 may be different

39. 
1) Slit lamp Examination
2) Scheimpflug image densitometry
measurements
Evaluation :

40. 
Scheimpflug image densitometry

41. 
After CXL,
1) Concomitant changes in the corneal
lamellar array and spacing may lead to an increase
in light scatter and a decrease in transparency.
2) A significant increase
in collagen fibril diameter, with increased
spacing between collagen fibrils, after CXL. This
may also play a role in decreased corneal
transparency.
Theories for haze

42. 
 3) CXL leads to an almost immediate loss of
keratocytes in the corneal stroma, activated
 keratocytes repopulated the corneal stroma,
 It is possible that these activated keratocytes
contribute to the development of CXL associated
corneal haze.

43. 
1) Mild haze is considered a normal finding in most of
cases and even a sign of success and usually doesn't
affect vision
2) Mild Haze is usually paracentral in position and
regressing in course with topical steriods
2) Risk factors for severe haze include advanced
keratoconus and Epi-off CXL.
Haze , is it a problem ?

44. 
Mild haze in postoperative epi-off CXL in The
Future center for corneal surgeries

45. 
Severe haze

46. 
High Fluence CXL

47. 
High intensity CXL includes delivery of Higher amount
of energy by high fluence CXL devices which will
lead to shortening the operation time.
This technique is based on a law of physics “ Bunsen-
Roscoe “ it states that an effect should stay the same ,
If the total energy remains the same “

48. 

49. 
To short the exposure time
1- Decrease dehydration time
2- To lessen keratocyte damage
Aim of high fluence CXL

50. 
Preliminary results about high fluence
CXL show a good safety profile as It
affects neither endothelial density nor
speed of epithelial healing which is an
indicator of limbal stem cell function.
Is it safe ???

51. 
However , further evaluation is needed to determine
the biochemical effects and overall safety profile, and
also the we should note that CXL is an oxygen
dependant process that depends on intrastromal
oxygen concentration which will be consumed more
with higher fluencies so it may affect the treatment
efficacy.
Controversy

52. 
Oxygen and CXL

53. 
To compensate for low oxygen ,
pulsed CXL is recommended

54. 
•The KXL® System (Avedro) accelerated CXL

55. 
Treatment parameters for Transepithelial crosslinking

57. 
1- Which type to use ??
2- Are they effective??
3- Combined CXL and Rings

58. 
Intacs
Ferrara ring
MyoRing

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64. 
1- INTACS :
Implanted in a 6mm diameter of the visual axis
Reduction in its use has occurred after appearance of
other types of rings which implanted in 5mm
diameter .
NB: the nearer to the visual axis the more flattening
effect .
Which Type to use ???

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66. 
2- Kerarings :
- Most commonly used , implanted in 5mm diameter
around the steepest axis.
- Wide range of ring dimensions for different
refractions and keratometry readings.

67. 
Keraring

68. 
Nomogram for Keraring

69. 
Tunnel creation by Femtosecond laser

70. 
Kerarings Ring implantation

71. 
Pentacam image shows area of central flattening effect of
Kerarings with regularization of the corneal surface

72. 
3- Myoring :
The most recent type , one segment ring , mainly
indicated for central (nipple) cone .

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Myoring

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The nomogram for selection of a type of ring depends mainly
on central average corneal keratometry (average Sim K)
Nomogram for myoring
(average Sim K) Implant diameter Implant thickness
< 44 7 mm 280um
44<ASK<48 6mm 240um
48 <ASK< 52 6mm 280um
52<ASK< 55 5mm 280um
> 55 5mm 320um

75. 
Tunnel creation by femtosecond laser

76. 
Pentacam image shows area of central marked flattening effect of
Myoring with regularization of the corneal surface

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78. 
Preoperative refraction :
-3.00Ds -4.75Dc@100
BCVA : 6/38
A 23ys patient of keratoconus who is
subjected to keraring implantation

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Preoperative Pentacam

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Postoperative refraction :
-1.50Ds -2.25@100
BCVA : 6/12

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Postoperative pentacam

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84. 
What ICRS actually do ??
1- Induce corneal flattening.
2- Mechanical support to the cornea.
3- Improvement of V/A.
IS ICRS implantation an effective
technique ?

85. 
1- Unpredictable results.
2- Improvement in V/A is of mild degrees.
3- Patient usually needs another optical
correction.
4- Night glare.
Problems

86. 
1- Stage (2) 50: 59 Ds
2- Clear cornea
3- BCVA > or = 6/60
4- Pachymetry at ring insertion > 400 um
5- high patient motivation
Indications

87. 
Keraring Myoring
Ring type One or two Segments
Incomplete ring
One complete ring
Site of
implantation
Tunnel Pocket
Incision site At steepest Axis Temporal
Difficulty Less difficult More difficult
Depth of
insertion
At 80% at insertion site At 80% of thinnest location
Type of cone Eccentric cone Central cone
CXL technique Transepithelial Intrastromal
Centration of
rings
A round visual axis A round the pupil
Suitable for High cylinder High sphere
Size of incision Small Large
Flattening effect Less More
Effect on corneal
thickness
Less thinning More thinning
Cost Less More

88. 
CXL plus

89. 
All includes CXL
1) CXL + PRK
2) CXL + ICRS
3) CXL + Toric Phakic IOL
Combined therapy for
Keratoconus

90. 
Combined CXL with topography-
guided, partial PRK which can correct
high amounts of irregular astigmatism
in keratoconic eyes. Partial PRK
includes correction of 70 % of sphere
and 70 % of cylinder in order not to
exceeds 50 um of stromal removal .
CXL + PRK “ Athens
protocol “

91. 

92. 
A comparison of the preoperative (left) and
7-month postoperative (middle) Pentacam images showing
significant normalization of the cone, keratometric flattening,
and improved symmetry. The difference map is on the right.

93. 
1- What is the minimum pachymetry for the
protocol ???
2- What are limits of sphere and cylinder for the
protocol ???
3- Is the aim of the protocol to reduce corneal
irregularity for better fitting of hard contact
lens or for optical correction without hard
contact lens???
Many questions need to be
answered:

94. 
After contact with Dr. John
Kanellopoulos by E-mail

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96. 
However :
1-There is a controversy about the safety
of the protocol
2- Only correct mild degrees of errors.
3- Better for postlasik ectasia

97. 
CXL AND ICRS
IMPLANTATION

98. 
Can a combination of CXL and ICRS
implantation offer an enhanced
treatment option in eyes with
keratoconus?

99. 
A combination of these two less invasive
treatments could, therefore,
theoretically provide optimal results
because the benefits of the procedures
would complement each other.

100. 
1- RINGs + CXL in same session
2- RINGs after CXL
3- CXL after RINGs
SEQUENCE OF
TREATMENTS

101. 
ICRS followed by CXL in patients with keratoconus
achieved better results than CXL followed by ICRS.
It is unnecessary to perform ICRS implantation and
CXL treatment simultaneously, because healing at
the incision site is extremely important. After
femtosecond channel creation with a 1-mm incision,
epithelialization and perfect healing can be achieved
by the end of the first postoperative day

102. 
Incomplete tunnel creation is one of the most common
complications of femtosecond laser channel creation,
as bridges in the tunnel may cause problems during
ICRS implantation. So increasing the energy level is
or decreasing spot separation is suggested to avoid
these complications.

103. 
A 22 ys old female with keratoconus grade (2)
Subjected to Epi-on CXl ,followed by kerarings
implantation after 2 months
Preoperative refraction( post CXL ) :
-5.5 Ds -1.75Dc @65 with BCVA :
6/48
From our experience in Sohag
Future Center for corneal surgeries

104. 
Preoperative pentacam

105. 

106. 
Postoperative refraction :
-2.25Ds -1.00@10
BCVA : 6/30

107. 
Postoperative pentacam

108. 

109. 
At the end

110. Thankyou