Long Term Corneal Endothelial Cell Loss in eyes with Clear Grafts after Penetrating Keratoplasty for Keratoconus

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Long Term Corneal Endothelial Cell Loss in eyes
with Clear Grafts after Penetrating Keratoplasty
for Keratoconus

• Dr. Gerald Zaidman1,2 , Angela Vong1

1New York Medical College, Valhalla, NY 2
Ophthalmology, Westchester Medical Center,
Valhalla, NY
The authors have no financial interest in the
subject matter of this poster.
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INTRODUCTION

• Endothelial trauma from ocular surgery,
  specifically penetrating keratoplasty, is known
  to significantly reduce endothelial cell counts
  (ECC). Poor vision, contact lens intolerance, and
  scarring are indications for corneal transplant
  surgery (PKP) in keratoconus (KCN). After PKP,
  there can be a decreased ECC in the recipient
  cornea. To date we know of no study that measures
  ECC loss years after PKP for KCN. Our study aims
  to measure long-term ECC loss after PKP for KCN.

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METHODS

• Endothelial cell counts were measured in eyes
  that had PKP performed by one surgeon, GWZ, from
  1994 2008 for KCN. Counts were done using Konan
  NSP-7700 Specular Microscopy. Only eyes with
  clear grafts were analyzed. ECC was compared to
  the original donor ECC. Eyes were divided into
  groups based on years following PKP
• - Group A 1 2 years
• - Group B 3 5 years
• - Group C 6 9 years
• - Group D 10 14 years
• We also analyzed eyes that had cataract surgery,
  refractive surgery, or more than 2 rejection
  episodes after PKP.

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RESULTS

Figure 2. Eye following Penetrating Keratoplasty
Figure 1. Keratoconus
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RESULTS

• Endothelial cell counts were performed on 63
  eyes. Patients averaged 46 years old, ranging
  from 29 66 years old.

Group Years after surgery No. of Eyes Mean cell loss Median Cell loss
A 1 2 18 2722 20
B 3 5 18 4616 48
C 6 9 15 5617 59
D 10 14 12 6214 64
Figure 3. Percentage of Endothelial Cell Loss
Following PKP in Uncomplicated Eyes
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Figure 4. ECC 1-2 Years after PKP
Figure 5. ECC 3-5 Years after PKP
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Figure 7. ECC 10-14 Years after PKP
Figure 6. ECC 6-9 Years after PKP
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Figure 5. Percentage of Endothelial Cell Survival
following PKP
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RESULTS
No. of eyes Mean cell loss Median cell loss
Cataract sx after PKP 7 6313 63
Refractive sx after PKP 7 5817 64
gt2 rejection episodes 8 5920 63

• Figure 6. Penetrating Keratoplasties analyzed
  with other surgeries and rejection episodes

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RESULTS

• Best corrected visual acuity of 60 eyes were
  20/40 or better. 3 eyes had poor vision one due
  to cystoid macular edema and 2 in a handicapped
  patient who could not be refracted.

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CONCLUSIONS

• There is continuing long term ECC loss years
  after PKP with the greatest loss in the first 5
  years following surgery. Corneal clarity and
  visual acuity were not affected. Best corrected
  visual acuity were 20/40 or better in nearly all
  eyes. Cataract surgery, refractive surgery, and
  resolved rejection episodes also led to
  endothelial cell loss but did not affect corneal
  clarity.

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REFERENCES

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