Long-term evaluation of endothelial cell changes in Fuchs corneal dystrophy: the influence of phacoemulsification and penetrating keratoplasty

Abstract

Purpose: To evaluate the natural course of the long-term endothelial cell changes in Fuchs corneal dystrophy (FCD) patients and investigate the effects of phacoemulsification on the annual rate of change in endothelial indices in FCD patients.

Methods: Thirty-four patients diagnosed with FCD at Seoul National University Hospital from 1994 to 2010 were retrospectively reviewed. Sixteen patients who had been followed up for more than 1 year were selected and classified into 3 groups: group A, patients with no ocular surgery; group B, patients who had undergone phacoemulsification only; and group C, patients who had undergone penetrating keratoplasty with cataract surgery. Endothelial cell density, polymegethism, pleomorphism, and pachymetry were measured and the exponential rates of endothelial cell and pachymetry change were analyzed.

Results: A non-linear mixed model of non-operated FCD patients showed that only pachymetric data tended to increase with statistical significance (p = 0.001) with a mean follow-up period of 4.15 years. Using an exponential regression analysis fitting curve, the mean rates of annual endothelial cell loss were 0.82%/yr, 20.39%/yr, and 29.27%/yr in groups A, B, and C respectively, and statistical significance was seen only in group C (p < 0.05).

Conclusions: Retrospective long-term follow-up data showed that changes in endothelial density did not significantly decrease over at least 4 years in middle-aged FCD patients. The changes in pachymetric corneal thickness appeared to increase over the same period. Considering that no exponential changes were aggravated after performing cataract surgery alone, cataract surgery would be a preferable option in FCD patients compared to an approach of "wait-and-do" penetrating keratoplasty combined with cataract surgery.

Keywords: Endothelial cell density; Fuchs corneal dystrophy; Pachymetry; Phacoemulsification.

Fig. 1

Exponential curve fitting model. (A) The mean rates of endothelial cell loss were 0.82% per year, 20.39% per year, and 29.27% per year in groups A, B, and C respectively. However, only the rate in group C was statistically significant (p < 0.05). (B) The mean rates of pachymetric change were -1.81% per year, +1.21% per year, and +1.89% per year in groups A, B, and C respectively, but showed no statistical significance. (C) The mean rates of coefficient of variances change were +1.94% per year, +1.21% per year, and +0.48% per year in groups A, B, and C respectively, but showed no statistical significance. (D) The mean rates of hexagonality change were -1.04% per year, -8.06% per year, and -1.19% per year in groups A, B, and C respectively, but showed no statistical significance. ECC = endothelial cell count.

Fig. 2

Exponential curve fitting regression model in non-Fuchs patients who underwent penetrating keratoplasty and cataract surgery. (A) The mean rate of endothelial cell loss was 19.43% per year with statistical significance, while the loss rate was 29.27% per year in group C (Fuchs corneal dystrophy patients who underwent keratoplasty and cataract surgery simultaneously). (B) The mean rate of pachymetric change was +0.13% per year, and in contrast, +1.89% per year in group C. (C) The mean rate of coefficient of variances change was +1.21% per year, and +0.48% per year in group C. (D) The mean rate of hexagonality change was -0.48% per year and -1.19% per year in group C. ECC = endothelial cell count.