Corneal Wound: Architecture and Integrity

1
Corneal Wound Architecture and Integrity

• Luis E. Fernández de Castro, M.D.1
• Helga P. Sandoval, M.D., M.S.C.R.1
• Kerry D. Solomon, M.D.1

1 Magill Research Center for Vision Correction,
Storm Eye Institute, Medical University of South
Carolina, Charleston, SC, USA
Disclosure L.E. Fernández de Castro-D Alcon,
Allergan, AMO H.P. Sandoval-D Alcon, Allergan,
AMO K.D. SolomonA,C,D Alcon, Allergan, AMO,
Advanced Medical Research, BL, InSite Vision,
Eyemaginations
Supported in part by NIH/NEI EY-014793 (vision
core) and an unrestricted grant to MUSC-SEI from
Research to Prevent Blindness, New York, NY, USA
2
Introduction

• Surgeons transitioning from larger to smaller
  micro-incisions
• Incision construction is key for preventing
  hypotony, wound leaks, and ingress of
  microorganisms (endophthalmitis)

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Purpose

• To compare different incision sizes on clear
  corneal incision (CCIs) and to determine which
  incision width creates a square or nearly square
  arquitecture

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Materials and Methods

• A prospective study of 4 human cadaver eyes using
  different incisions (4) were analyzed
• Particular attention was given to ensure that the
  wound had a square or near square configuration
• Scanning electron microscopy was used to evaluate
  wound architecture in each group

3.2 mm
2.8 mm
2.6 mm
2.2 mm
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Materials and Methods

• After the CCIs
• Corneas were fixed in 2 Cacodylate
  Glutaraldehyde
• Processed and examined using SEM at the Medical
  University of South Carolina, Charleston, SC
• Imaging was performed using a magnification
  factor of 50x, 100x, and 200x
• Each specimen was examined and then photographed
  according to a standard protocol
• The outer and inner corneal wound surface were
  evaluated

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Results

• Qualitative observations
• On the epithelial side
• All incisions were adequately apposed
• Large incision width
• Rectangle configuration
• Small incision width
• Square configuration

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3.2 mm Incision
Tear of Descemet membrane
Epithelial cell loss Apposed
Gapping
Outer
Inner
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2.8 mm Incision
Epithelial cell loss Apposed
Gapping
Outer
Inner
9
2.6 mm Incision
Epithelial cell loss Gapping
Apposed Tear at the edge
Outer
Inner
10
2.2 mm Incision
Apposed
Gapping
Outer
Inner
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Smaller incision widths permit a nearly squared
or squared configuration
Larger incision widths prevent a square
configuration
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Conclusion

• Larger incision widths often preclude a square
  construction due to infringement on the visual
  axis
• Smaller incision width permit a nearly square or
  square construction
• Square incisions can be more stable than
  rectangular
• Reducing risk of hypotony
• Reducing risk of wound leakage
• Reducing ingress of microorganisms
• Irregular apposition and minimal gapping in
  endothelial edges due to direct mechanical trauma
• Clinically shown to improve over time
• Ongoing study to determine wound integrity