Corneal Epithelial Healing After LASIK Surgery

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Corneal Epithelial Healing After LASIK Surgery
Category P5 Refractive

• Yousuf Khalifa, MD
• Tracie Sponseller, OD
• David Bogorad, MD

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Introduction

• LASIK flap creation and stromal ablation elicit
  healing responses in the corneal epithelium and
  stroma
• Physiology of corneal stroma healing after LASIK
  surgery has been described
• Corneal epithelial wound healing after LASIK
  surgery has not been reported previously to our
  knowledge
• Insights into the factors involved in corneal
  epithelium healing can be drawn from LASIK
  surgery

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Methods

• 65 consecutive LASIK surgery patients were
  included
• LASIK flaps created with the Moria M2
  microkeratome, with Moria disposable heads, using
  published nomograms
• Alcon Ladarvision 4000 platform used
• Conventional, Custom, Myopic, and Hyperopic
  corrections included
• Prednisolone Acetate 1 and Vigamox were
  prescribed tid along with Systane qid prn
• Patients evaluated at postoperative day 1 with
  fluorescein staining to assess number of clock
  hours healed

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Methods

• Patient age, sex, treatment refraction,
  microkeratome suction ring and flap thickness,
  ablation depth, time of LASIK, elapsed time from
  surgery, number of stained clock hours entered
  into Excel spreadsheet
• SAS version 9.1 was used for all analyses and
  statistical significance was assessed at the 5
  level

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Results
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Results
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Results
A Bland-Altman plot illustrates that the majority
of the eyes within each subject are within the
limits of agreement. Thus, the measurement of
clock hours is in agreement for the two eyes
within each subject and that healing did not
differ between the eyes.
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Results
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Results
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Results
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Discussion

• LASIK surgery is an ideal model to study human
  epithelial wound healing
• Our results show that suction ring size, flap
  thickness, ablation depth have no correlation
  with epithelial healing
• Fluorescein staining is a simple, safe,
  clinically accepted means of assessing epithelial
  integrity
• Our study lays the foundation for future studies
  looking at factors that influence epithelial
  healing
• Postoperative Day 1 is an excellent window to
  assess the epithelial healing because of the
  range of healed clock hours. In our study the
  elapsed time from surgery ranged from 16 to 26
  hours.

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Discussion

• OD and OS healing rates are consistent within
  each patient
• Using the same blade on the OS after the OD does
  not affect epithelial healing
• Between 16 and 26 hours after LASIK surgery the
  epithelial healing varies but the further out
  from surgery, the more likely to have more healed
  clock hours
• Age did not closely correlate
• Smoking status did not correlate
• This study is likely underpowered to determine
  the effects of smoking