Corneal endothelium and postoperative outcomes 15 years after penetrating keratoplasty

doi:10.1016/j.ajo.2004.09.045

American Journal of Ophthalmology

Volume 139, Issue 2, February 2005, Pages 311-319

https://doi.org/10.1016/j.ajo.2004.09.045 Get rights and content

Purpose

To determine changes in the central endothelium and thickness of grafted corneas and the cumulative probability of developing glaucoma, of graft rejection, and of graft failure 15 years after penetrating keratoplasty.

Design

Longitudinal cohort study of 500 consecutive penetrating keratoplasties by one surgeon.

Methods

Regrafted eyes, fellow eyes of bilateral cases, and patients not granting research authorization were excluded, leaving 388 grafts for analysis. At intervals after surgery, we photographed the endothelium and measured corneal thickness using specular microscopy. The presence of glaucoma, graft rejection, and graft failure were recorded.

Results

The 67 patients examined at 15 years represented 30% of the available clear grafts. Endothelial cell loss from preoperative donor levels was 71 ± 12% (mean ± standard deviation, n = 67), endothelial cell density was 872 ± 348 cells/mm², and corneal thickness was 0.59 ± 0.06 mm. Endothelial cell density was unchanged between 10 and 15 years, whereas corneal thickness increased (P = .001, n = 55). The mean annual rate of endothelial cell loss from 10 to 15 years after surgery was 0.2 ± 5.7% (n = 54). The cumulative probability of developing glaucoma, graft rejection, or graft failure was 20%, 23%, and 28%, respectively, and 6 of the 8 graft failures after 10 years resulted from late endothelial failure.

Conclusions

From 10 to 15 years after penetrating keratoplasty, the annual rate of endothelial cell loss was similar to that of normal corneas, corneal thickness increased, and late endothelial failure was the major cause of graft failure.

Section snippets

Methods

The cohort consists of 500 consecutive patients who had penetrating keratoplasty performed by one surgeon (W.M.B.) between 1976 and 1986. Thirty-six repeat grafts and 70 fellow eyes were excluded from the study, leaving 394 grafts in 394 patients (i.e., 394 independent observations) available for analysis to 10 years after surgery. For the 15-year data, 6 patients had withdrawn research authorization, leaving 388 grafts available for analysis. There were 141 (36%) male and 247 (64%) female

Results

Of the 394 patients from the original analysis, 84% of the grafts were for Fuchs’ dystrophy, keratoconus, or corneal edema from aphakia or pseudophakia (Table 1). Sixty-seven patients (30% of the clear grafts available for follow-up) returned for their 15-year postoperative examination. At 15 years, 76 grafts were known to have failed and 107 patients were known to have died, reducing the overall cohort by 164 because 19 graft failures and deaths occurred in the same patients (Table 2). A

Discussion

From the original 394 patients in this cohort who underwent penetrating keratoplasty by the same surgeon, 67 attended for a 15-year follow-up examination. Although the 67 patients only represent 30% of the cohort presumed alive and without graft failure, these data are valuable in the long-term prospective evaluation of the corneal endothelium and outcomes after penetrating keratoplasty and represent the largest such cohort in the literature. Although the patients who did not return at 15 years

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Endothelial failure and immunological graft rejection remain long-term complications leading to late graft failure in penetrating keratoplasty (PK). Deep anterior lamellar keratoplasty (DALK) has emerged as a viable alternative that enables preservation of the host's endothelial cells to eliminate risks of endothelial rejection and failure. The aim of this study was to compare long-term graft survival between PK and DALK.
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: Supported in part by National Institutes of Health grant EY 02037 (W.M.B.), and Research to Prevent Blindness, Inc., New York, New York.

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Original articlesCorneal endothelium and postoperative outcomes 15 years after penetrating keratoplasty

Purpose

Design

Methods

Results

Conclusions

Section snippets

Methods

Results

Discussion

Am J Ophthalmol

Ophthalmology

Ophthalmology

Ophthalmology

Corneal transplantation techniques

Morphologic and functional evaluation of the endothelium of transplanted human corneas

Trans Am Ophthalmol Soc

Predicting endothelial cell loss and long-term corneal graft survival

Invest Ophthalmol Vis Sci

Nonparametric estimation from incomplete observations

J Am Stat Assoc

Functional measurements on the enlarged endothelial cells of corneal transplants

Trans Am Ophthalmol Soc

Original articles
Corneal endothelium and postoperative outcomes 15 years after penetrating keratoplasty