Comparison of outcomes of penetrating keratoplasty versus Descemet’s stripping automated endothelial keratoplasty for penetrating keratoplasty graft failure due to corneal edema

Abstract

To evaluate the outcomes of repeat corneal transplantation, either penetrating keratoplasty (PKP) or Descemet's stripping automated endothelial keratoplasty (DSAEK), for penetrating keratoplasty grafts which failed due to corneal edema. The charts of 24 eyes with failed PKP grafts, due to corneal edema, which underwent a repeat corneal transplant (PKP in 17 eyes [Group 1] and DSAEK in seven eyes [Group 2]) between 2003 and 2007 were retrospectively reviewed. There was no statistically significant difference in the median postoperative visual acuity between the two groups at 1, 2, or 3 years. In Group 1, two (18%) eyes had a final visual acuity ≥ 20/40, in contrast to four (80%) eyes in Group 2, which was statistically significant (P = 0.038). Seven (41%) of the Group 1 eyes developed postoperative complications compared to only one (14%) eye in Group 2. Eleven (65%) of the Group 1 eyes and five (71%) of Group 2 eyes had clear grafts on the last examination. There was no statistically significant difference in the graft survival rate for Group 1 versus Group 2 at 3 years (57.9% vs 68.6%, P = 0.507). There was a trend towards better postoperative visual acuity, a lower postoperative complication rate, and a higher graft survival rate in eyes that underwent DSAEK rather than repeat PKP for graft failure secondary to corneal edema. Given this small, retrospective study, future studies comparing repeat PKP with DSAEK are warranted to determine which procedure allows for improved outcomes.

Endothelial Keratoplasty After Failed Penetrating Keratoplasty: An Alternative to Repeat Penetrating Keratoplasty

“…Kitzmann and associates found no statistically significant differences in postoperative BCVA between the 2 groups at 1, 2, or 3 years. 23 Similarly, we found significant improvement in postoperative BCVA in both groups and at 1 year, but no significant differences in BCVA at the 1 year follow-up between the repeat PK group and EK under PK group (P ¼ .185).…”

“…37 In this nested study from our prospective cohort of corneal grafts, we found significantly prolonged graft survival in eyes that underwent EK under a failed PK, compared to the repeat PK group at up to 5 years followup (cumulative survival probability 86.4% vs 51.3%, respectively, log-rank P value ¼ .013). This suggests a significant long-term graft survival advantage of performing EK under a failed PK in patients who suffer initial corneal 14,23 and 21%-70% for repeat PK. [10][11][12][13][14][15][16][17][18] Of note, graft rejection episodes were more common in the repeat PK group compared to the EK under PK group, albeit nonsignificant, likely owing to the small sample size (13.6% vs 3.1%, P ¼ .174)-despite having no significant differences in immunosuppression regime.…”

“…22 Kitzmann and associates found a trend toward better 3-year graft survival in 7 eyes that underwent EK compared to 17 eyes that had a repeat PK (57.9% vs 68.6%, P ¼ .507), although this result was not statistically significant (likely owing to the small sample size). 23 In addition, the authors found no statistically significant differences in postoperative best-corrected visual acuity (BCVA) between the 2 groups at 1, 2, or 3 years, 23 although others have reported significant improvements in postoperative BCVA in EK after failed PK. 22,24,26,27 To date, there are no studies that have conclusively shown better outcomes for EK after failed PK, compared to repeat PK.…”

“…19,20 Initial studies have found graft survival rates of EK under a failed PK to be around 55%-100% at 1 year. [21][22][23] However, many of these studies were noncomparative case series, with a limited follow-up period. 21,[23][24][25][26][27] Of the few studies that examined long-term graft survival, Anshu and associates found a graft survival rate of 74% at 4 years (up to 96% in a subgroup of patients without previous glaucoma shunt surgery).…”

“…[21][22][23] However, many of these studies were noncomparative case series, with a limited follow-up period. 21,[23][24][25][26][27] Of the few studies that examined long-term graft survival, Anshu and associates found a graft survival rate of 74% at 4 years (up to 96% in a subgroup of patients without previous glaucoma shunt surgery). 22 Kitzmann and associates found a trend toward better 3-year graft survival in 7 eyes that underwent EK compared to 17 eyes that had a repeat PK (57.9% vs 68.6%, P ¼ .507), although this result was not statistically significant (likely owing to the small sample size).…”