Descemet Membrane Endothelial Keratoplasty for Failed Penetrating Keratoplasty: Visual Outcomes and Graft Survival

Abstract

Purpose: To evaluate outcomes and graft survival of Descemet membrane endothelial keratoplasty (DMEK) for failed penetrating keratoplasty (PK). Methods: Ninety-three DMEK procedures performed in 84 eyes of 77 patients with failed PK were retrospectively reviewed. The main outcomes were corrected distance visual acuity and graft survival assessed with Kaplan–Meier survival analysis and proportional hazards modeling taking follow-up into consideration. Results: Sixty-nine eyes had 1 previous failed PK, 13 had 2, 1 had 3, and 1 had 4. Ten eyes had failed Descemet stripping endothelial keratoplasty (DSEK) performed under failed PK. Fourteen cases (15%) had previous glaucoma filtration surgery (9 trabeculectomy alone; 5 trabeculectomy and aqueous shunt). Median follow-up was 21 months (range, 1 month to 7 years). Median Snellen corrected distance visual acuity improved from 20/100 preoperatively (range, 20/30 to count fingers) to 20/30 at 6 months postoperatively (n = 73; range, 20/20–20/200). Rebubbling rates were 53% when the diameter of the DMEK graft was oversized, 27% when same sized, and 33% when undersized relative to that of the previous PK graft. Two grafts (2%) experienced an immunologic rejection episode, and 15 (16%) failed, including 5 primary/early failures and 10 late failures. Previous glaucoma surgery was the only significant risk factor for failure (relative risk, 7.1; 95% confidence interval, 2.1–37.0). The 1-, 2-, and 3-year graft survival rates were 96%, 89%, and 89% without versus 78%, 53%, and 39% with previous glaucoma surgery. Conclusions: Treatment of failed PK with DMEK produced similar 4-year survival (76%) and better visual outcomes than previously reported with Descemet stripping endothelial keratoplasty or an initial PK regraft.

Preoperative Evaluation in Descemet Membrane Endothelial Keratoplasty for Secondary Penetrating Keratoplasty Graft Failure

“…Visual recovery and central pachymetry improvement were relatively fast during the study period (Table 2). Those favorable clinical outcomes are consistent with other studies as well [16,18,22]. The visual recovery with DMEK under failed PK contrasts sharply with the delayed and unpredictable visual rehabilitation after re-PKP [29].…”

“…Common conclusions have emerged from multiple previous studies regarding the results of DMEK after PKP compared to primary DMEK [16,18,19,22,23], including higher rebubbling rates, higher endothelial cell density loss, higher late graft failure rates and more demanding surgical technique. Furthermore, glaucoma ltering surgeries, which are probably more prevalent in post-PKP eyes, are considered a signi cant risk factor for late graft failure, probably as a result of altering the microenvironment in the aqueous humor which accelerates endothelial cell loss [24].…”

Long‐term outcome of descemet membrane endothelial keratoplasty (DMEK) following failed penetrating keratoplasty (PK)

“…Anshu et al reported 2013 in a small cohort ( n = 6) a ECD loss of 33% at 6 months. Pasari et al (2019) reported 2019 in a larger cohort ( n = 93) ECD loss rates of 31% at 6 months, 44% at one year and 47% at two years. Einan‐Lifshitz et al reported a ECD loss of 41% at 6 months and 48% at one year ( n = 28) (Einan‐Lifshitz et al 2018).…”

“…The visual outcome is comparable to other reported studies. Pasari et al (2019) reported that 74% of their cohort consisting of 69 eyes achieved an improved VA at 12 months postoperatively. In our cohort, 87.5% of the documented 12‐month BCVA values were better when comparing to the VA before surgery.…”

“…Price et al reported a series of 93 eyes with a mean follow-up of 21 months and concluded that DMEK is an effective option in managing secondary graft failure after PK with good visual outcomes and mid-term graft survival (Pasari et al 2019). Heinzelmann et al examined the midterm outcome of 19 eyes over almost one year with mostly bullous keratopathy as primary indication and also concluded that DMEK is a feasible e901 option even in eyes with limited visual potential (Heinzelmann et al 2017).…”