Four-Year Survival Comparison of Endothelial Keratoplasty Techniques in Patients With Previous Glaucoma Surgery

Donor Corneal Endothelial Cell Maturity and Its Impact on Graft Survival in Glaucoma Patients Undergoing Corneal Transplantation

PURPOSE

To examine corneal graft survival via corneal endothelial cell density (ECD) and corneal endothelial cell loss (ECL) at 5 years post-transplantation in the eyes of patients with and without a history of undergoing glaucoma surgery according to the maturity of the donor corneal endothelial cells.

DESIGN

Prospective cohort study.

METHODS

This prospective cohort study included 17 patients with glaucoma and 51 patients without glaucoma who underwent Descemet's stripping automated endothelial keratoplasty or penetrating keratoplasty at the Baptist Eye Institute, Kyoto, Japan, between October 2014 and October 2016. Human corneal endothelial cells were cultured from residual peripheral donor cornea tissue, and the maturity of the cells was evaluated by cell surface markers (ie, CD166+, CD44-/dull, CD24-, and CD105-) using fluorescence-activated cell sorting. Kaplan-Meier analysis or the chi-square test was used to assess the rate of successful corneal graft survival post-transplantation.

RESULTS

At 36 months postoperatively, the mean ECD and ECL in the glaucoma-bleb eyes were 1197 ± 352 cells/mm2 and 55.5% ± 13.9% in the high-maturity group and 853 ± 430 cells/mm2 and 67.7% ± 18.1% in the low-maturity group, respectively. Kaplan-Meier analysis revealed that at 5 years postoperatively, the overall rate of survival was 45%, that is, 100% in the high-maturity group and 25% in the low-maturity group (P < .05).

CONCLUSIONS

The findings in this prospective cohort study revealed that the use of donor corneal grafts containing mature-differentiated corneal endothelial cells could maintain the survival of the transplanted graft for a long-term period, even in patients with a history of undergoing glaucoma surgery.

Changes in the Visual Field Test after Descemet Stripping Automated Endothelial Keratoplasty in Advanced Glaucoma

Background: To evaluate changes in the visual field (VF) after Descemet stripping automated endothelial keratoplasty (DSAEK) in eyes with advanced glaucoma and previous trabeculectomy. Methods: Changes in VF, best-corrected visual acuity (BCVA), intraocular pressure (IOP), and number of glaucoma medications were analyzed before and after DSAEK in 19 eyes. The VFs were evaluated using the 10-2 program of the Humphrey Field Analyzer (HFA) and/or Goldmann perimetry (GP). Results: In nine eyes, the MD improved from -22.24 ± 6.5 dB to -18.36 ± 5.1 dB in HFA. In five out of nine eyes, postoperative MD improved >1 dB compared to preoperative MD. In GP testing, 10 out of 15 eyes showed an improvement, that is, greater than 20° in VF enlargement by the isopter of I-4e and/or new detection of a smaller or darker isopter. Overall, improvement in VF with the HFA and/or GP test was observed in 12/19 (63.2%) eyes after DSAEK. Postoperative BCVA improved by more than two lines in logMAR VA in 18 of 19 (94.7%) eyes. There were no significant differences between the preoperative and postoperative IOP and the number of glaucoma medications. Conclusions: DSAEK may produce subjective improvement in the visual field as well as improved visual acuity, even in advanced glaucomatous eyes.

Risk Factors for Descemet Membrane Endothelial Keratoplasty Rejection: Current Perspectives- Systematic Review

Descemet membrane endothelial keratoplasty (DMEK) is a corneal endothelial transplantation procedure with selective removal of a patient's defective Descemet membrane and endothelium. It is replaced with a healthy donor Descemet membrane and endothelium without a stromal component. Corneal graft rejection can be at the level of epithelium, stroma as well endothelium. DMEK graft rejection is relatively less common than rejection with DSAEK or penetrating keratoplasty, and a good outcome may be achieved with prompt management. The clinical picture of DMEK rejection is usually similar to endothelial rejection in Descemet Stripping Endothelial Keratoplasty (DSEK/DSAEK), which generally manifests as pain, redness, reduction in visual acuity, stromal edema, endothelial rejection line, keratic precipitates at the back of the cornea and corneal neovascularization. However, more subtle forms of rejection or immune reactions are more common in DMEK compared to DSAEK eyes. Early clinical diagnosis, prompt intervention, and meticulous management safeguard visual acuity and graft survival in these cases. Intensive topical steroids form the mainstay in the management of DMEK rejection. Sometimes, oral or intravenous steroids or other systemic immunomodulators may be required. DMEK graft failure can be primary or secondary, and failure usually requires a second procedure in the form of repeat DMEK or DSEK or penetrating keratoplasty (PKP). A detailed literature search was performed using search engines such as Google Scholar, PubMed, and Google books, and a comprehensive review on DMEK rejection was found to be lacking. This review is a comprehensive update on the risk factors, pathophysiology, primary and secondary graft failure, recent advances in diagnosis, prevention of rejection, and updates in the management of DMEK rejection. The review also discusses the differential diagnosis of DMEK failure and rejection, prognosis, and future perspectives considering DMEK failure and rejection.

Graft failure rate and complications after Descemet membrane endothelial keratoplasty in eyes with pre-existing glaucoma

PURPOSE

To evaluate the outcome of Descemet Membrane Endothelial Keratoplasty (DMEK) in eyes with pre-existing glaucoma.

DESIGN

In this retrospective, observational case series we included data of 150 consecutive DMEKs in eyes with pre-existing glaucoma of 150 patients after excluding data of the second treated eye of each patient and of re-DMEKs during follow-up. Cumulative incidences of IOP elevation (IOP > 21 mmHg or ≥ 10 mmHg increase in IOP from preoperative value), post-DMEK glaucoma (need of an additional intervention due to worsening of the IOP), graft rejection, and graft failure rate were analyzed using Kaplan-Meier survival analysis. COX regression analysis was used to evaluate independent risk factors.

RESULTS

The 36-month cumulative incidence of IOP elevation was 53.5% [95 CI 43.5-63.5%] and of post-DMEK glaucoma 36.3% [95 CI 26.3-46.3%]. Graft rejection occurred with a 36-month cumulative incidence of 9.2% [CI 95% 2.3-16.1]. None of the analyzed risk factors increased the risk for the development of graft rejection. The 36-month cumulative incidence of graft failure was 16.6% [CI 95% 8.4-24.8]. Independent risk factors for graft failure were the indication for DMEK "status after graft failure" (n = 16) compared to Fuchs' dystrophy (n = 74) (p = 0.045, HR 8.511 [CI 95% 1.054-68.756]) and pre-existing filtrating surgery via glaucoma drainage device (GDD) (n = 10) compared to no surgery/iridectomy (n = 109) (p = 0.014, HR 6.273 [CI 95% 1.456-27.031]).

CONCLUSION

The risks of postoperative complications (IOP elevation, post-DMEK glaucoma, graft rejection, and graft failure) in patients with pre-existing glaucoma are high. In particular, pre-existing filtrating surgery via GDD implantation-but not trabeculectomy-and DMEK after graft failure increase the risk of graft failure.

Corneal Endothelial Cell Loss in Glaucoma and Glaucoma Surgery and the Utility of Management with Descemet Membrane Endothelial Keratoplasty (DMEK)

The corneal endothelium has a crucial role in maintaining a clear and healthy cornea. Corneal endothelial cell loss occurs naturally with age; however, a diagnosis of glaucoma and surgical intervention for glaucoma can exacerbate a decline in cell number and impairment in morphology. In glaucoma, the mechanisms for this are not well understood and this accelerated cell loss can result in corneal decompensation. Given the high prevalence of glaucoma worldwide, this review aims to explore the abnormalities observed in the corneal endothelium in differing glaucoma phenotypes and glaucoma therapies (medical or surgical including with new generation microinvasive glaucoma surgeries). Descemet membrane endothelial keratoplasty (DMEK) is increasingly being used to manage corneal endothelial failure for glaucoma patients and we aim to review the recent literature evaluating the use of this technique in this clinical scenario.

Graft survival of Descemet membrane endothelial keratoplasty (DMEK) in corneal endothelial decompensation after glaucoma surgery

Purpose

This study aims to assess the results, rebubbling rate, and graft survival after Descemet membrane endothelial keratoplasty (DMEK) with regard to the number and type of previous glaucoma surgeries.

Methods

This is a clinical retrospective review of 1845 consecutive DMEK surgeries between 07/2011 and 08/2017 at the Department of Ophthalmology, University of Cologne. Sixty-six eyes were included: group 1 (eyes with previous glaucoma drainage devices (GDD); n = 27) and group 2 (eyes with previous trabeculectomy (TE); n = 39). Endothelial cell loss (ECL), central corneal thickness, graft failure, rebubbling rate, and best spectacle-corrected visual acuity (BSCVA) up to 3 years after DMEK were compared between subgroups of patients with different numbers of and the two most common types of glaucoma surgeries either GDD or TE or both.

Results

Re-DMEK rate due to secondary graft failure was 55.6% (15/27) in group 1 and 35.9% in group 2. The mean graft survival time in group 1 was 25 ± 11 months and 31.3 ± 8.6 months in group 2 (p = 0.009).

ECL in surviving grafts in group 1 was 35% (n = 13) at 6 months, 36% at 12 months (n = 8), and 27% (n = 4) at 2 years postoperatively. In group 2, ECL in surviving grafts was 41% (n = 10) at 6 months, 36% (n = 9) at 12 months, and 38% (n = 8) at 2 years postoperatively. Rebubbling rate in group 1 was 18.5% (5/27) and 35.9% (14/39) in group 2 (p = 0.079).

Conclusion

Eyes with previous GDD had no higher risk for an increased rebubbling rate but a higher risk for a re-DMEK due to secondary graft failure with a mean transplant survival time of about 2 years. Compared to eyes with preexisting glaucoma drainage device, eyes after trabeculectomy had less secondary graft failures and a longer mean graft survival rate.

Advances in corneal graft rejection

PURPOSE OF REVIEW

Immune rejection after corneal transplantation is a major risk for graft failure. We aim to summarize recent advances in the understanding and management of graft rejection.

RECENT FINDINGS

Immune rejection remains the leading cause of graft failure in penetrating keratoplasty (PKP). While ABO blood type and sex match between donor and recipient may reduce rejection, human leucocyte antigens class II matching in a randomized study did not reduce the risk of rejection in high-risk PKP. Compared with PKP, deep anterior lamellar keratoplasty, descemet stripping automated endothelial keratoplasty, and descemet membrane endothelial keratoplasty have lower immune rejection rates of 1.7-13%, 5-11.4%, and 1.7-2.8%, respectively, based on long-term (5 years and more) studies. Whether immune rejection is a major risk factor for graft failure in these lamellar keratoplasties is unclear. While there have not been major advances in the systemic management of graft rejection, topical nonsteroid agents such as tacrolimus and anti-vascular endothelial growth factor have shown promise in high-risk cases.

SUMMARY

Immune rejection remains the leading cause of graft failure in PKP. Lamellar keratoplasties have significantly lower rejection rates compared with PKP. The significance of rejection in the failure of lamellar grafts warrants further investigation.

Corneal transplant survival rate in glaucoma patients with multiple previous antiglaucoma surgeries

BACKGROUND

Glaucoma can cause corneal decompensation and accelerate the failure of the graft. Previous antiglaucoma operations are one of the most important risk factors for endothelial failure.

METHODS

In this retrospective study, 40 eyes of 40 glaucoma patients with advanced corneal decompensation after glaucoma surgery were treated with keratoplasty and outcomes were assessed for 24 months.

RESULTS

16, 9 and 15 eyes underwent Descemet Membrane Endothelial Keratoplasty (DMEK), Descemet's Stripping Automated Endothelial Keratoplasty (DSAEK) and penetrating keratoplasty (pKPL), respectively. Visual acuity improved at least 2 lines in 24 of 40 eyes after the three types of keratoplasty. All 40 eyes remained pain free for the follow-up period. The mean intraocular pressure (IOP) difference was not significantly different (p > 0.05) from the preoperative values 12 and 24 months after keratoplasty. The endothelial cell density of the donor cornea decreased from 2485.6 ± 165.18 to 1291.4 ± 467.1 and 1180.4 ± 397.2/mm² (p < 0.001) after 12 and 24 months, respectively. Nine eyes (22.5%) had therapy-resistant corneal decompensation in the context of a transplant failure and were treated with a re-keratoplasty (2 re-pKPLs, 3 re-DSAEKs and 3 re-DMEKs).

CONCLUSIONS

Eyes with previous glaucoma surgery show satisfying results after keratoplasty, mainly DMEK and pKPL.