EarlyOnset Astigmatism After EpiLASIK without Epithelial Flap Replacement

1
Early-Onset Astigmatism After Epi-LASIK without
Epithelial Flap Replacement

• Junki Sawai1, Ken Onda2, Keisuke Yoshida1
• Kobe Clinic1, Tokyo, Japan
• Fuchinobe General Hospital2, Sagamihara, Japan

2

• Purpose
• To examine the shot-term corneal astigmatism
  after Epi-LASIK as a trasient refractive
  complication.
• Methods
• All the procedure is performed by same surgeon1,
  with use of EC-5000CX2 (Nidek, Japan) and Epi-K
  (Moria, France). Before and after Epi-LASIK,
  TMS-2N (later upgraded to be TMS-4)
  video-keratoscope (Tomey, Japan) was applied to
  evaluate the corneal topography.
• Subject
• 435 patients (868 eyes, including the control and
  10 eyes with this study cases) were received the
  Epi-LASIK in Kobe Clinic since June 2005. The
  average refraction is shown with spherical as
  -6.275 /-5.252D and cylinder as -1.125
  /-1.220D. We found out 5 patients had the such
  prolonged symptom as double vision post
  Epi-LASIK. We followed-up these changes with
  their refraction and TMS. The observed period
  was more than 6 month.

3
Details of Epi-LASIK

• - The epithelium flap created by Epi-K was
  completely removed.
• - The ablated surface was rinsed off by the
  chilled 50cc BSS.
• Prophylactic mitomycin-C (MMC) was applied when
  the ablation depth over 100micron against high
  myopic cases.
• Every subject put on one-week use soft contact
  lenses for 4-7 days and was required to use auto
  serum eye drop postoperatively
• - The tapering usage of steroid eye drop is up to
  6 months.
• Postoperative Examination was performed in the
  next day, in 3 days,
• 1 week, 2 weeks, 3 weeks and once per a month
  from 1 to 6 months.

4
n.s.



n.s.
n.s.
n.s.
0
-1
-2
-3
n.s.
D
-4
Astigmatism cases (n 10eyes)
-5
Normal Cases (n 858eyes)
-6
Mean S.E. Astigmatism with the rule vs.
Normal Plt0.001 Plt0.01 Mann-Whitneys U-test
-7
-8
-9
2M
Pre-Ope.
Post-Ope.
1M
3M
4M
5M
6M
Figure1 Pre/Post Epi-LASIK Spherical Changes
5
-.2
n.s.
n.s.
n.s.
n.s.

-.4


-.6
n.s.
-.8
-1
D
-1.2
Astigmatism cases(n 10eyes)
-1.4
Control Cases (n858eyes)
-1.6
Mean S.E. Astigmatism vs. Control Plt0.001
Plt0.01 Mann-Whitneys U-test
-1.8
-2
-2.2
1M
Pre-Ope.
3M
4M
6M
Post-Ope.
2M
5M
Figure 2 Pre/Post Epi-LASIK Cylindrical Changes
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Case0, Age 32, Female. (control) Pre- and
Post-Epi-LASIK 1 Month and 3 Month data were
shown. Astigmatism was indicated at the post1M in
Left eye(shown as the arrow ?) disappeared when
Post3M. Uncorrected visual acuity (UCVA) with
both eyes were 1.5.
Pre OD S -3.5 C-1.25 A166 / OS S -5.5 C-1.5 A
179
Post 3M OD S 0.5 C-0.75 A80 / OS S 0.0
C-0.25 A163
Post 1M OD S -0.25 C-0.25 A75 / OS S -0.5
C-0.0 A0
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Case1, Age 46, Female. Her Left eye astigmatism
existed during post 3M period. The double vision
has improved distinctly after adding auto serum
eye drop. UCVA is 0.7 with R and 0.6 L
Pre OD S -7.0 C-0.25 A20 / OS S -7.0 C-0.75A136
Post 2M OD S -0.75 C-1.25 A4 / OS S -0.5 C-1.5
A177
Post 1M OD S -1.25 C-1.5 A11 / OS S -0.5
C-2.25 A172
Post 7M OD S -1.25 C-0.25 A20 / OS S -1.0
C-0.25 A162
Post 3M OD S -0.75 C-0.75 A15 / OS S -0.75
C-0.75 A163
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Case 2. Age 38, Male. Residual Astigmatism left
in his Left eye through 5M postoperatively.
After reapplied the auto serum eye drop,
subjective sign was improved. UCVA was 1.5 with
both eyes.
Pre OD S -12.0 C-0.25 A33 / OS S -10.5 C-0.75
A77
Post 1M OD S -1.25 C-1.25 A28 / OS S -1.5
C-0.75A180
Post 7M OD S -1.25C-0.25A57 / OS S -0.75 C-0.75
A78
Post 2M OD S -1.75 C-0.5 A10/ OS S -2.0 C-0.5
A172
9
Case3. Age 45, Male. Astigmatism existed after
5M. Enhancement was performed at the 7th month.
UCVA at the 9th month is R-1.2, L-1.5.
Post 1M OD S -1.5 C-1.75 A171 / OS S -0.25
C-1.75 A172
PreOD S -7.25 C-0.25 A7 / OS S -7.5 C-0.25 A102
Post 5M OD S -1.75 C-0.75 A3 / OS S -2.0 C-0.25
A6
Post 3M OD S -1.25 C-1.0 A178 / OS S -1.25
C-0.5 A180
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Summary of Case Study

• As for these 5 cases with astigmatism, their
  refractive data in 1 month shows the average of
  cylindrical equivalent is -1.700/-0.926D in 2M
  is -0.725 /-0.275D then in 3M is
  -0.625/-0.358D. (Figure.2)
• From TMS measurement around post1M, it indicated
  that a direct astigmatism occurred within 3-4mm
  in diameter in the middle of cornea. The grade of
  astigmatism will be reduced as well as
  regenerated epithelium. (Case0-3)
• If the residual Astigmatism is still indicated
  after 3 months, the enhancement should be
  considered. However, at least 6 months
  observation should be made. (Case3)

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Epi-LASIK is a laser corrective procedure after
bluntly removed the epithelium from the Bowmans
membrane, which is based on the anatomic and
embryologic difference of the corneas and
epitheliums re-growth. At our clinics, we
removed the epithelium flap completely and
confirmed the epithelium would re-covered
smoothly within 3 to 5 days post Epi-LASIK as
control cases. However, as we presented here,
we had experienced some cases may caused by
un-uniformity of epithelium thickness or
re-growth in early postoperative stages. These
un-uniformity differences occurred within
cell-level but not shown with microscopy finding
that could affect the stability of individual
vision. From this evaluation of early onset
astigmatism after Epi-LASIK, we rethink the
importance of focusing on the ocular surface
circumstance like tear film to reinforce
epithelium cell healing and re-growth.
Discussion
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Conclusion

• Post Epi-LASIK astigmatism, not existed before
  surgery, may occur as an early onset
  complication.
• Topographic analysis using TMS is effective as a
  comparative evaluation data for follow up.
• The timing to perform the enhancement should be
  after at least 6 months observation.
• The auto serum eye drops applying would be
  effective for cornea epithelium re-growth.