after

1
We have NO financial interest in any material
mentioned.
Late-onset
Corneal Scars
after
LASEK with Mitomycin C
Myoung Joon Kim, MD Hungwon Tchah, MD
Dept. of Ophthalmology
Univ. of Ulsan College of Medicine
Asan Medical Center
SOUTH KOREA
2
Case 1
VOD (0.03) Central corneal thickness 828?
M / 34 Visual loss of right eye
Hypertrophic corneal scar in the central cornea
4 months
11 months
LASEK with mitomycin C 15 months ago
Visual loss 4 months ago
No Hx of atopy, collagen vascular disease,
corneal abrasion, exposure to UV
3
Case 2
VOD 0.32 Thickness at corneal scar 794?
Rx -0.50Dsph (0.63)
F / 23 White patch on left eye
Hypertrophic scar in the paracentral cornea
2 months
12 months
LASEK with mitomycin C 14 months ago
White patch 2 months ago
No Hx of atopy, collagen vascular disease,
corneal abrasion, exposure to UV
4
Case 2
Corneal Thickness Total/Scar 860/460 ? Clear
stroma 860-460 400 ?
Hyperetrophic corneal scar in paracentral cornea
5
Mitomycin C use
LASEK
Late-onset subepithelial haze with elevation
Common Features
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Questions to be answered
Proper time for treatment
Etiology and Prevention
Treatment methods
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Case 1
Case 2
WHEN DECIDED TO TREAT
Time Duration from
16 months 5 months 1 months
LASEK with MMC Start of Corneal Haze First
visit
20 months 8 months 6 months
8
Case 2
Case 1
- SEE Video File attached separately -
2 weeks
3 weeks
9
Case 1
Case 2
Manual Debridement Postoperative
period UCVA Refraction BCVA CCT
3 weeks 0.03 ? 0.5 Plano 0.03 ? 0.63 -
2 weeks 0.2 ? 0.16 2.502.50x95 0.63 ?
0.63 436/408
DISORGANIZED COLLAGEN FIBERS
Case 1
Case 2
Smooth Muscle Actin ()
20 nm fibrils
Smooth Muscle Actin ()
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Case 1
Case 2
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Corneal Haze Formation after LASEK
? Damaged corneal epithelium ? Cytokine milieu
IL-1, TGF-ß ? Keratocyte apoptosis and
myofibroblast transformation ? ECM and
collagen ? Peaking at 3 months ? Resolution by
12 months ? Ablation amount matters ? Related
with atopy, collagen vascular disease, corneal
abrasion, exposure to UV ? Prophylactic use of
topical mitomycin C an akylating agent
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? Prophylactic use of intraoperative mitomycin
C? Shift of timeline of wound healing?
Delayed wound healing followed by aggressive
wound healing ? Influx of ACTIVATED
keratocytes and replacement of ECM
? In Summary, our cases were characterized by
late-onset corneal opacity and increased corneal
thickness, which may be related to intraoperative
use of mitomycin C. This type of hypertrophic
scar significantly decreases visual acuity even
after treatment, therefore additional studies
will be necessary to investigate the underlying
causes and mechanisms to prevent such adverse
effects.