Transcript Document

Demographic and visual outcomes
on keratoconus patients with failed
“epi- on”C3R cross-linking
procedures
Yaron S. Rabinowitz M.D.
Oana Dumitrascu M.D.
The authors have no financial interest in the materials
presented in this poster
Background
The standard procedure in collagen crosslinking is to remove the epithelium. Recent
reports suggest that it is not necessary to
remove the epithelium using the “epi-on”
C3R procedure. This study was undertaken
to illustrate C3R failures.
Abstract
PURPOSE: To present data on unhappy keratoconus patients
who presented to our office following C3R “epi-on” cross-linking.
METHODS: Retrospective chart review 1 year post procedure
RESULTS: 13 eyes were identified. Mean age was 33 yrs
(range 23 – 41). Mean uncorrected acuity was 20/200
(range 20/40-20/200). Mean best-corrected acuity was 20/60
(range 20/30-20/200). Mean central pachymetry was 435um
(range 380-485). Mean K value was 50.27(range 43-58).
Mean I-S value was 4.25(range 1.84-10.86). 4 eyes had
repeat cross-linking with the standard epi-off procedure, 4 eyes
had corneal transplants and 5 eyes had no further treatment
CONCLUSIONS: These data suggest that the “epi-on” C3R
procedure may not be optimal for treating keratoconus.
Results - Demographics of failed “epi-on”
N
Age
Reason for consult
UCVA
BSCVA
K’s
Pach
Additional findings/surgery
1
14
Progressed 7D in 1 year
20/400
20/80
57/53
417
Clear cornea
2
14
Progressed 8D in 1 year
20/400
20/70
58/52
444
Intacs
3
26
Progressed by 3D
CF 2 ft
20/400
54/48
446
Paracentral scar
4
28
No visual improvement
20/150
20/30
51/49
409
Intacs and ICL
5
28
No visual improvement
20/80
20/40
46/42
473
Intacs and ICL
6
32
No improvement in VA
20/40
20/25
45/42
479
Intacs and 2nd C3R
7
32
No improvement in VA
20/80
20/40
50/51
454
Intacs and 2nd C3R
8
33
Rapid progression
CF
20/400
54/41
381
Intacs
9
36
Progression worse VA
20/40
20/40
56/45
418
Intacs, CK and ICL
10
36
Progression worse VA
20/70
20/40
57/48
435
Intacs, CK and ICL
11
42
Progression worse VA
20/400
20/70
53/48
380
Paracentral scar
12
42
Progression worse VA
20/150
20/70
50/47
461
Paracentral scar
13
51
No improvement in VA
CF 1ft
CF 1ft
63/56
381
Paracentral scar/Epi Lasik
Results Demographics
Summary of findings at presentation
•
•
•
•
4/13 (30%) eyes had paracentral scars
9/13 (70%) eyes had 1 additional surgery
6/13 (46%) eyes had 2 additional surgeries
3/13 (23%) eyes had 3 additional surgeries
Results - reasons why
patients not happy
8/13(60%) patients noted
progression after C3R, we were
able to document this in 5 patients
one progressed up to 8D
5/13(40%) did not experience an
improvement in their vision which
was their reason for doing the
procedure
Eye 2 - Pre op and 1 year Post op
topography C3R - 8 D change
Results - Disposition of Failed C3R patients
N
Age
UCVA
BSCV
A
K’s
Pach
Disposition and results
1
14
20/400
20/80
57/53
417
I.E.K./AK
UCVA 20/30
2
14
20/400
20/70
58/52
444
I.E.K./LASIK
UCVA 20/25
3
26
CF 2 ft
20/400
54/48
446
RGP
BCVA 20/60-
4
28
20/150
20/30
51/49
409
Glasses
BSCVA 20/30-
5
28
20/80
20/40
46/42
473
Glasses
BSCVA 20/80-
6
32
20/40
20/25
45/42
479
Repeat CXL epi off
UCVA 20/30
7
32
20/80
20/40
50/51
454
Repeat CXL epi off
UCVA 20/50
8
33
CF
20/400
54/41
381
I.E.K/LASIK
UCVA 20/20
9
36
20/40
20/40
56/45
418
Repeat CXL epi off
UCVA 20/40
10
36
20/70
20/40
57/48
435
Repeat CXL epi off
UCVA 20/70
11
42
20/400
20/70
53/48
380
RGP
BCVA 20/60-
12
42
20/150
20/70
50/47
461
RGP
BCVA
13
51
CF 1ft
CF 1ft
63/56
381
I.E.K./AK
UCVA 20/30
20/70
Discussion
Collagen Cross Linking(CXL) involves the removal of the corneal
epithelium, soaking the cornea with riboflavin and applying a
homogenous beam of UV light for about 30 minutes to the
cornea.
Several studies in the published literature suggest that this is a safe
and effective method for retarding the progression of
keratoconus
C3R is a variation of this procedure in which the epithelium is
retained and a lamp of unknown origin is used for UV radiation.
It is not FDA approved but done on an off label basis
This procedure is heavily marketed as being safe and effective,
with a < 2% retreatment rate being quoted
For C3R,there have been no scientific studies to date
demonstrating a high safety profile as has been done for CXL
Discussion
In this study we demonstrate that 13 eyes from one
practice performing C3R had an unfavorable
outcome in a 1 year period
This suggests that the “failure rate” for C3R may be
higher than the quoted 1.4% “retreatment rate”
5/13 eyes were unhappy because they noticed no visual
improvement, 4 had paracentral scars
8/13 eyes noted definite progression within 1 year of
receiving the treatment
This suggests that patient selection for this particular
procedure might have been less than optimal
Conclusion
While Collagen Cross linking (CXL) appears to be safe
and effective as described by the pioneers of this
procedure, it appears that performing this procedure
leaving the epithelium on requires further study for
safety and efficacy, before being universally adopted.
Patients expectations for improved vision should be
tempered with the emphasis being placed on
retarding the progression, which currently has a
quoted 7.6% retreatment rate using the standard
“epi-off” CXL procedure