Clinical profile of graft detachment and outcomes of rebubbling after Descemet stripping endothelial keratoplasty

Suture Fixation to Reduce Graft Detachment in Descemet Stripping Endothelial Keratoplasty

PURPOSE

The aim of this study was to report the outcomes of graft fixation using interrupted, full-thickness sutures on graft detachment after Descemet stripping endothelial keratoplasty (DSEK).

METHODS

All DSEK procedures performed at Mayo Clinic, Rochester, MN, from 2015 through 2022 were retrospectively reviewed. Risk factors for graft detachment were defined as previous incisional glaucoma surgery, previous penetrating keratoplasty, or absence of the normal lens-capsule barrier. Cases were categorized into sutured, high-risk grafts; unsutured, high-risk grafts; and unsutured, low-risk grafts. The primary outcome was graft detachment, and secondary outcomes were early graft failure and graft clarity at 12 months after surgery.

RESULTS

Demographics between the high-risk groups were similar for sex and age at the time of surgery. Graft detachment occurred in 4 of 97 sutured, high-risk eyes (4.1%) and 24 of 119 unsutured high-risk eyes (20.2%) ( P = 0.002). In comparison, graft detachment occurred in 18 of 181 unsutured low-risk eyes (9.9%). The incidence of early graft failure was 2.1%, 5.0%, and 3.3% and late graft failure by 12 months was 9.8%, 12.8%, and 4.2%, respectively.

CONCLUSIONS

In eyes with high-risk factors for graft detachment, suture fixation of the graft in DSEK decreased graft detachment to a rate at least as low as that in low-risk eyes.

Incidence and management of early postoperative complications in lamellar corneal transplantation

PURPOSE

To provide a comprehensive review of the incidence, risk factors, and management of early complications after deep anterior lamellar keratoplasty (DALK), Descemet stripping automated keratoplasty (DSAEK), and Descemet membrane endothelial keratoplasty (DMEK).

METHODS

A literature review of complications, that can occur from the time of the transplant up to 1 month after the transplant procedure, was conducted. Case reports and case series were included in the review.

RESULTS

Complications in the earliest postoperative days following anterior and posterior lamellar keratoplasty have shown to affect graft survival. These complications include, but are not limited to, double anterior chamber, sclerokeratitis endothelial graft detachment, acute glaucoma, fluid misdirection syndrome, donor-transmitted and recurrent infection, and Uretts-Zavalia syndrome.

CONCLUSION

It is essential for surgeons and clinicians to not only be aware of these complications but also know how to manage them to minimize their impact on long-term transplant survival and visual outcomes.

[Risk factors for failure of pre-cut eye bank UT-DSAEK grafts]

INTRODUCTION

The main risk factors for graft failure in penetrating keratoplasty are well known. However, few studies have examined donor characteristics or more precise data on endothelial keratoplasty.

MATERIALS AND METHODS

This was a retrospective, single-center study at the Nantes University Hospital, aiming to identify factors predictive of one-year success or failure of eye bank UT-DSAEK endothelial keratoplasty grafts prepared between May 2016 and October 2018. The outcome measure was success or failure at 12months post keratoplasty.

RESULTS

One hundred and five grafts were included: 93 successes and 12 failures at 12months. The failure rate was higher in 2016 compared to 2017 and 2018. The characteristics associated with higher failure rate were elderly donor, shorter time between harvesting and grafting, lower endothelial cell density, significant pre-graft endothelial cell loss, re-graft for Fuchs dystrophy, history of corneal transplant.

DISCUSSION

Our results are consistent with those in the literature. However, some factors, such as the type of corneal harvesting or pre-graft endothelial cell loss, were not found. UT-DSAEK has demonstrated better results than DSAEK, but still appears to be somewhat inferior to DMEK.

CONCLUSION

The main factor for graft failure in our study was an early re-graft within 12months. However, the low incidence of graft failure limits interpretation of these results.

Case Report: Primary graft failure due to a reversed lenticule in Descemet Stripping Automated Endothelial Keratoplasty

Introduction and importance: This report details the clinical features and management in a case of Descemet stripping automated endothelial keratoplasty (DSAEK) which had primary graft failure (PGF) due to an inverted yet attached lenticule. Presentation of case: A 66-year-old gentleman had poor visual recovery in the right eye after undergoing cataract surgery 12 years prior to presentation. The visual acuity was counting fingers and examination revealed endothelial decompensation. The patient underwent a DSAEK and postoperatively had a well attached lenticule. However, the cornea was edematous three weeks after the surgery and optical coherence tomography (OCT) revealed a reversed lenticule. The patient underwent a repeat DSAEK and had an uneventful postoperative course. The visual acuity was 20/40 after 7 months with a clear cornea and a well attached graft. Discussion: PGF is a rare complication following DSAEK which occurs due to poor endothelial function of the donor graft. Insertion of a reversed lenticule may get overlooked as a cause of PGF unless the graft edge profile is examined on an OCT scan. The graft in the current case was well attached despite its inverted position suggesting that graft adherence is perhaps not a function of the corneal endothelial pumps in isolation and may be driven by factors such as the intraocular pressure. Conclusion: A reversed DSAEK lenticule may have normal adherence to the host stroma and must be considered in cases with PGF. OCT of the graft edge is required for diagnosis before performing a repeat keratoplasty.

Considerations for Corneal Surgery With Patients in the 10th Decade of Life

PURPOSE

The purpose of this study was to report the indications, ocular and systemic comorbidities, and surgical outcomes of corneal transplantation in patients older than 90 years.

METHODS

A retrospective review was conducted to identify individuals 90 years and older who underwent corneal transplantation surgery at the Bascom Palmer Eye Institute between January 2013 and October 2020. Outcomes included best-corrected visual acuity and graft survival over time. Paired t tests were used to compare visual acuity preoperatively versus postoperatively. Graft survival was evaluated with Kaplan-Meier curves.

RESULTS

Fifty-eight eyes of 52 consecutive individuals were included. The mean age of individuals was 92 ± 2 years; 26.9% were male; and 48.1% self-identified as non-Hispanic White and 38.5% as Hispanic. Postoperative follow-up was 14.7 ± 12.1 months. Of the 58 eyes, 44.8% (26/58) underwent penetrating keratoplasty, 46.6% (27/58) Descemet stripping automated endothelial keratoplasty, and 6.9% (4/58) keratoprosthesis. All surgeries were performed under monitored local anesthesia, without major complications. Surgical indications included pseudophakic bullous keratopathy (36.2%), glaucoma-associated corneal decompensation (27.6%), Fuchs endothelial dystrophy (25.9%), and perforated corneal ulceration (19.0%). The best-corrected visual acuity improved by 0.32 (95% confidence interval 0.14-0.50; P < 0.01) as early as 1 month postoperatively, and vision gains were sustained for at least 12 months. Graft survival probability at 12 months was 88%.

CONCLUSIONS

Corneal transplantation is a safe and successful procedure in restoring the visual acuity for patients older than 90 years after careful preoperative evaluation. Further research is needed to evaluate the impact of corneal transplantation on quality of life in patients in the 10th decade of life.

Secondary Endothelial Keratoplasty-A Narrative Review of the Outcomes of Secondary Corneal Endothelial Allografts

BACKGROUND

We review the literature on the efficacy and safety outcomes of secondary Descemet stripping endothelial keratoplasty (DSEK) and Descemet membrane endothelial keratoplasty (DMEK).

METHODS

Literature search of English-written publications up to September 27, 2020 in PubMed database, using the terms "endothelial keratoplasty" in combination with keywords "secondary" or "repeat." In addition, we manually searched the references of the primary articles.

RESULTS

Twenty-seven studies (n = 651 eyes) were retained and reviewed, including 10 studies on repeat DSEK, 8 studies on repeat DMEK, 6 studies of DMEK following DSEK, and 3 studies of DSEK after failed DMEK. All studies reported significant improvement in visual acuity after secondary endothelial keratoplasty (EK). Twelve studies compared visual outcomes between primary and secondary EK, reporting conflicting findings. Sixteen studies reported endothelial cell loss rates after secondary EK, and only 1 study reported significantly increased endothelial cell loss rates compared with primary EK. Allograft rejection episodes occurred in 1.8% of eyes (range, 0%-50%). Six studies compared complication rates between primary and secondary EK eyes, and only 1 study found a higher median number of complications. However, 2 studies reported higher regraft failure rates compared with primary EK eyes.

CONCLUSIONS

Secondary EK is surgically feasible and renders significant visual improvement after failed primary EK, although it is not clear whether visual outcomes and allograft survival are comparable with primary EK, raising the question of whether secondary EK eyes are "low risk" as primary EK eyes. Further larger, prospective studies are encouraged to obtain additional quality data on secondary corneal endothelial allotransplantation.

Graft detachments in endothelial keratoplasty

Graft detachment is the most common complication of endothelial keratoplasty. With the ongoing advancements in the field of endothelial keratoplasty, our understanding of risk factors of graft detachments and its management has been evolving. Various prevention measures have been described in literature including presoaking the donor graft, anterior chamber tamponade, venting incisions, sutures to prevent dislocation of graft. Management of a detached graft involves secondary interventions such as rebubbling, suturing and regrafts. In this review, we discuss graft detachment in different types of endothelial keratoplasty techniques including Descemet stripping endothelial keratoplasty, Descemet stripping automated endothelial keratoplasty and Descemet's membrane endothelial keratoplasty; with emphasis on incidence, risk factors, preventive measures and their management.

Outcomes of rebubbling for graft detachment after Descemet's stripping endothelial keratoplasty or Descemet's stripping automated endothelial keratoplasty

Purpose

To study the outcomes of rebubbling for graft detachment after Descemet's stripping endothelial keratoplasty (DSEK) or Descemet's stripping automated endothelial keratoplasty (DSAEK).

Methods

From 2260 eyes that underwent DSEK or DSAEK from July 2008 to June 2015, 80 eyes of 80 patients developed graft detachment and were retrospectively reviewed. Host-related, surgery-related and donor-related factors that have a bearing on graft adhesion were looked at retrospectively, and eventual outcomes after rebubbling procedure were studied.

Results

Successful attachment was observed in 77 (96.25%) eyes and clear grafts were achieved in 55 (68.75%) eyes, while 25 (31.25%) eyes had graft failure. The uncorrected and best-corrected distance visual acuities significantly improved from 1 month to 3 months post-operatively and remained stable till 12 months of follow-up. Three lenticules that failed to attach with the first rebubbling procedure underwent a second rebubbling, two underwent a repeat DSEK with good outcomes and four underwent penetrating keratoplasty. On evaluating possible risk factors for graft failure, lower donor endothelial cell density was found to be a significant factor (P = 0.03). The median graft survival following rebubbling was 30 months.

Conclusion

Rebubbling procedure in detached grafts after DSEK or DSAEK can reattach the lenticule in 96% of eyes in immediate post-operative period and the majority of the grafts remained clear on long-term follow-up with a median graft survival period of 2.5 years.

Repeat keratoplasty in failed Descemet stripping automated endothelial keratoplasty

Purpose:

To evaluate the clinical factors associated with repeat Descemet stripping automated endothelial keratoplasty (DSAEK) or penetrating keratoplasty (PKP) in cases of failed DSAEK.

Methods:

Retrospective observational study of cases with failed DSAEK admitted to our center for a repeat keratoplasty over 5 years (January 2013–Decemeber 2017) was undertaken. Demographic and perioperative details of all cases and type of repeat keratoplasty were recorded. Logistic regression analysis was performed to analyze the factors affecting the type of repeat keratoplasty.

Results:

A total of 94 eyes with failed DSAEK were evaluated. Repeat DSAEK was performed in 66% and PKP in 34% of cases. Significantly increased odds for requiring PKP were observed in association with stromal scarring [odds ratio (OR) = 2.9, P = 0.018)], trainee surgeons (OR = 4.05, P = 0.008), intraoperative complications (OR = 4.58, P = 0.003), scleral fixated intraocular lens or anterior chamber intraocular lens in situ (OR = 33.8, P < 0.001), secondary glaucoma (OR = 3.02, P = 0.015), peripheral anterior synechiae (OR = 8.6, P < 0.001), preoperative corneal thickness (OR = 1.01, P < 0001), time to primary surgery (OR = 1.03, P = 0.03), post-DSAEK host thickness (OR = 1.01, P < 0.001), and time interval from graft failure to regraft (OR = 1.18, P < 0.001). All eyes with congenital hereditary endothelial dystrophy, bee-sting-induced corneal decompensation, Axenfeld-Rieger syndrome, and multiple failed grafts underwent secondary PKP. All cases (nine eyes) that required surgical intervention for secondary glaucoma underwent secondary PKP (P < 0.001).

Conclusion:

Repeat DSAEK is feasible in up to two-third of cases of failed DSAEK. A PKP is required in one-third of cases, and various preoperative, intraoperative and postoperative factors are associated with unsuitability for repeat DSAEK.

Lower risk of graft dislocation applying organ cultured corneas compared with cold short-term cultured corneas during DSAEK surgery

BACKGROUND

To investigate factors that may affect graft dislocation after uneventful Descemet stripping endothelial keratoplasty (DSAEK), with a special focus on different donor cornea storage conditions.

METHODS

All DSAEK surgeries performed during 6 years in our hospital were retrospectively investigated. Patients with previous intraocular surgeries other than cataract extraction were excluded. Donor data (age, gender, death-to-preservation time, cornea storage conditions, graft storage time, and estimated thickness of the graft) and patient information (age, gender, and indication for surgery) were noted.

RESULTS

A total of 26 dislocations (6.6%) out of 394 DSAEK surgeries were found. The dislocation rate was considerably reduced between 2011 and 2016, due to more experienced surgeons. There was a significantly higher dislocation rate with the use of donor corneas stored in cold storage solution (12.7%) compared with organ culture solution (2.5%) (P < 0.001). During the study period, donor corneas stored in cold storage solution and organ culture solution were applied in 158 (40%) and 236 (60%) cases, respectively. There were no differences in recipient age and gender between patients who received corneas from the two storage systems, indicating a random distribution of grafts. In a multivariate analysis, only operation year (reduced rate over the years) and cold storage solution were statistically significantly associated with graft dislocation.

CONCLUSION

This study suggests that the type of storage solution may have a decisive role in graft dislocation in DSAEK surgery.

Factors Influencing Graft Endothelial Cell Density after Descemet Stripping Automated Endothelial Keratoplasty

Purpose:

To determine the factors that influence the endothelial cell density (ECD) of donor grafts after Descemet stripping automated endothelial keratoplasty (DSAEK).

Methods:

This retrospective, interventional case series comprised 77 eyes of 64 patients who underwent DSAEK. Confocal microscopy was performed at the final follow-up examination to evaluate the endothelial cell count, cell morphology, and graft thickness. Univariate and multiple linear regression analyses were used to investigate recipient-, donor-, surgical-, and postoperative related variables capable of influencing graft endothelial cell counts after DSAEK.

Results:

The mean patient age was 62.3 ± 15.6 years; patients were followed-up for 26.2 ± 20.9 months postoperatively. Forty-six eyes (59.7%) underwent stand-alone DSAEK; 31 eyes (40.3%) underwent DSAEK combined with cataract surgery. The donor trephination size was 8.0 ± 0.21 mm. The mean donor age was 30.4 ± 11.2 years, and the mean preoperative endothelial cell density was 3127.4 ± 315.1 cells/mm², which decreased to 1788.6 ± 716.5 cells/mm² postoperatively (P < 0.001). The mean postoperative central graft thickness was 102.4 ± 31.6 μm. Univariate analysis revealed that postoperative ECD was significantly associated with death to preservation time (P = 0.046), graft thickness (P = 0.016), follow-up duration (P = 0.005), and graft non-attachment (P = 0.049). Multiple regression analyses identified graft thickness (β = 10.62, P = 0.003) and follow-up duration (β = -22.09, P = 0.001) as the significant characteristics influencing postoperative ECD.

Conclusion:

The primary predictors of ECD after DSAEK were graft thickness and duration of follow-up. Surgeons’ requests for ultrathin DSAEK donor grafts to improve visual outcomes might not have the desired postoperative outcome with respect to ECD.

Factors Associated With Graft Detachment After Primary Descemet Stripping Automated Endothelial Keratoplasty

PURPOSE

To identify risk factors associated with postoperative graft detachment after Descemet stripping automated endothelial keratoplasty (DSAEK).

METHODS

In this retrospective institutional cohort study, the study group included all consecutive eyes that underwent primary DSAEK between January 2005 and October 2015 at Villa Serena-Villa Igea private hospitals (Forlì, Italy) and developed postoperative graft detachment (n = 45). The control group included all eyes that underwent primary DSAEK during the same period and did not develop graft detachment (n = 1167). The main outcome measure was whether or not postoperative graft detachment occurred.

RESULTS

Main indications for surgery included Fuchs endothelial dystrophy (525/1212 = 41%), pseudophakic bullous keratopathy (422/1212 = 35%), and a failed penetrating keratoplasty (PK) graft (190/1212 = 16%). Postoperative graft detachment occurred in 45 of 1212 (3.7%) eyes. Medically treated glaucoma, previous trabeculectomy, previous aqueous shunt procedure, and failed PK were all associated with an increased risk for graft detachment in univariate analysis. No particular lens status at the time of graft implantation was significantly associated with graft detachment, including the presence of an anterior chamber intraocular lens [odds ratio (OR), 1.5; 95% confidence interval (CI), 0.35-6.46, P = 0.58] or aphakia at the time of graft transplantation (OR, 1.37; 95% CI, 0.41-4.57, P = 0.74). Cataract removal during surgery was not associated with an increased risk for detachment (OR, 0.77; 95% CI, 0.39-1.5, P = 0.47). Previous trabeculectomy (OR, 4.21; 95% CI, 1.53-11.56, P = 0.005) and a previous failed PK graft (OR, 3.04; 95% CI, 1.6-5.78, P = 0.001) were the only independent risk factors for graft detachment in multivariate analyses.

CONCLUSIONS

Previous PK and trabeculectomy are independent risk factors for postoperative graft detachment in primary DSAEK.

Combined DSEK and Transconjunctival Pars Plana Vitrectomy

We report here three patients who underwent combined Descemet's stripping with endothelial keratoplasty and transconjunctival pars plana vitrectomy for bullous keratopathy and posterior segment pathology. A surgical technique and case histories are described. Anatomic and visual outcomes of combined Descemet's stripping with endothelial keratoplasty and vitrectomy were excellent. Our experience provides technical guidelines and limitations. The combined minimally invasive techniques allow for rapid anatomical recovery and return of function and visual acuity in a single sitting.

Risk Factors Predicting the Need for Graft Exchange After Descemet Stripping Automated Endothelial Keratoplasty

PURPOSE

To identify the risk factors predicting the need for graft exchange after Descemet stripping automated endothelial keratoplasty (DSAEK).

METHODS

This is a retrospective cohort study. The study group included all 117 eyes that underwent or necessitated repeat DSAEK performed between January 2005 and June 2014 at Villa Serena-Villa Igea private hospitals (Forlì, Italy). The control group consisted of 1033 eyes that underwent only primary DSAEK during the same period. Demographic details, indications for primary surgery, ocular preoperative status and comorbidities, donor endothelial cell density (ECD), and postoperative complications were compared between the groups using univariate and multivariate analyses.

RESULTS

The prevalence of graft failure necessitating graft exchange was 10.2% (117 of 1150 eyes). In univariate analysis, a diagnosis of Fuchs endothelial dystrophy was a protective factor against the risk of repeat DSAEK. Prior trabeculectomy or aqueous shunt implantation, postoperative graft detachment, lower donor ECD, and a rejection episode were all associated with a significantly higher risk of requiring repeat DSAEK. The presence of buphthalmos, anterior chamber intraocular lens, aphakia, or prior penetrating keratoplasty were not risk factors for the failure of DSAEK. Of these variables, multivariate analysis showed that only prior aqueous shunt implantation [odds ratio (OR) = 5.5, 95% confidence interval (CI), 1.4-22.2], lower donor ECD (OR = 0.99, 95% CI, 0.997-0.999), and a documented postoperative rejection episode (OR = 18.2, 95% CI, 7.9-45.0) predicted the need for repeat DSAEK.

CONCLUSIONS

DSAEK grafts have similarly good long-term survival regardless of the indication for surgery, lens status, or ocular comorbidities, with the only exception being the presence of an aqueous shunt.

Determinants of visual quality after endothelial keratoplasty

Endothelial keratoplasty is now favored over full-thickness penetrating keratoplasty for corneal decompensation secondary to endothelial dysfunction. Although endothelial keratoplasty has evolved as surgeons strive to improve outcomes, fewer patients than expected achieve best corrected visual acuity of 20/20 despite healthy grafts and no ocular comorbidities. Reasons for this remain unclear, with theories including anterior stromal changes, differences in graft thickness and regularity, induced high-order aberrations, and the nature of the graft-host interface. Newer iterations of endothelial keratoplasty such as thin manual Descemet stripping endothelial keratoplasty, ultrathin automated Descemet stripping endothelial keratoplasty, and Descemet membrane endothelial keratoplasty have achieved rates of 20/20 acuity of approximately 50%, comparable to modern cataract surgery, and it may be that a ceiling exists, particularly in the older age group of patients. Establishing the relative contribution of the factors that determine visual quality following endothelial keratoplasty will help drive further innovation, optimizing visual and patient-reported outcomes while improving surgical efficacy and safety.

Outcomes of endothelial keratoplasty in pseudophakic corneal oedema: with or without Descemet's membrane stripping

AIMS

To evaluate and compare outcomes of Descemet's stripping endothelial keratoplasty (DSEK) with non-DSEK (nDSEK) in pseudophakic corneal oedema (PCE).

METHODS

The study was a prospective, non-consecutive, comparative, interventional case series. Twenty-six patients with PCE were randomised into two groups. Group 1 comprised of those cases that had undergone conventional DSEK, and group 2 consisted of those that had nDSEK for PCE between 2010 and 2012. The data on demographics and clinical characteristics were collected from all patients. Any intraoperative and early and late postoperative complications were also noted. The primary outcome measure was postoperative functional success. Graft survival and complications were analysed as secondary outcomes.

RESULTS

The median best-corrected visual acuities at 6 months postoperatively in groups 1 and 2 were 0.18 (IQR 0.10-0.30) and 0.44 (IQR 0.18-0.51), respectively (p=0.11). Corneal oedema cleared in all patients. During the early postoperative period, a patient in group 2 had lenticule detachment managed by rebubbling.

CONCLUSIONS

nDSEK has outcomes similar to DSEK in PCE with advantages of decreased surgical time and avoidance of inadvertent pull on the posterior stromal fibres that may occur during Descemet's stripping.

Complications and management in Descemet's stripping endothelial keratoplasty: analysis of consecutive 430 cases

Purpose:

To analyze the complications and their managements in Descemet's stripping endothelial keratoplasty (DSEK) in consecutive 430 cases by single surgeon in a tertiary eye hospital.

Materials and Methods:

430 eyes of 366 patients with endothelial dysfunctions scheduled for DSEK, were analyzed retrospectively. In all cases donor dissection was performed manually, and ‘Taco’ insertion and unfolding technique was used. Intra-operative and postoperative complications with their managements and outcomes were reviewed retrospectively. Periodic endothelial cell density was analyzed for each patient till the last visit. Follow-up period was between 3 to 60 months (mean 18.7 months).

Results:

13 (3.0%) eyes had operative complications during donor dissection and 16 (3.7%) had during recipient procedure. In 7 (1.6%) eyes, donor lenticule was replaced with a new one during the surgery. In early postoperative period, 21 (4.9%) eyes had donor dislocation and 12 (2.8%) eyes had air-induced pupillary block; and they were managed immediately. 2 cases had primary graft failure and in 1 case had postoperative bacterial endophthalmitis requiring evisceration. In late postoperative period, 48 (11.3%) eyes had secondary glaucoma and 14 (3.3%) eyes had late secondary graft failure. Endothelial rejection occurred in 5 (1.2%) cases. Mean endothelial cell loss was 19.7% after 3 months and 54.2% after 5 years. Total graft failure in this series was 31 (7.2%) and in 17 cases re-DSEK was performed successfully.

Conclusions:

Both operative and postoperative complications do occur in DSEK. Most of these complications can be managed by medical or appropriate surgical means. Some of the complications can be avoided and reduced with experience.

Center and surgeon effect on outcomes of endothelial keratoplasty versus penetrating keratoplasty in the United Kingdom

PURPOSE

To compare national outcomes of endothelial keratoplasty (EK) and penetrating keratoplasty (PK) during comparable 6-year periods.

DESIGN

Prospective cohort study of national registry data.

METHODS

SETTING

United Kingdom National Transplant Registry, 2000 through 2011, inclusive.

PATIENT POPULATION

All United Kingdom patients undergoing first EK (n = 2074) for Fuchs endothelial dystrophy or pseudophakic bullous keratopathy from January 2006 through December 2011. Comparison cohort of patients undergoing first PK (n = 2622, same indications, January 2000 through December 2005).

OBSERVATION PROCEDURE

Year of surgery, surgeon and center experience, corneal diagnosis, donor factors, patient factors, and surgical risk factors were analyzed against graft survival and visual outcomes.

RESULTS

For both Fuchs endothelial dystrophy and pseudophakic bullous keratopathy, EK achieved better average best-corrected acuity and lower refractive error. For both groups, graft failure was significantly higher for EK than PK. EK failure in Fuchs endothelial dystrophy was associated with center experience (hazard ratio [HR], 2.3; P < .0001), donor endothelial density (HR, 1.8; P = .01), glaucoma at time of surgery (HR, 2.1; P = .003), and donor age older than 75 years (HR, 1.3; P = .05). EK failure in pseudophakic bullous keratopathy was associated with center experience of fewer than 15 cases (HR, 2.0; P < .0001) and glaucoma at time of surgery (HR, 1.7; P = .002).

CONCLUSIONS

Prospective national registry data for EK showed higher graft failure than is seen in PK or in retrospective case series of EK. Higher failure rates may be acceptable given established benefits of the procedure, including lower refractive error, structural globe integrity, and faster visual recovery. Center experience influenced EK survival more than surgeon experience, and overall surgical outcomes may be improved by standardized techniques and support within experienced units.

Optimizing outcomes with Descemet's membrane endothelial keratoplasty

PURPOSE OF REVIEW

To review recent advances in posterior lamellar keratoplasty and to describe strategies that enhance the outcome of Descemet's membrane endothelial keratoplasty (DMEK) and should lead to a more widespread use of this technique.

RECENT FINDINGS

DMEK offers significant advantages over Descemet's stripping automated endothelial keratoplasty (DSAEK) such as less immune reaction and better visual acuity because of less higher order aberrations. Donor selection should exclude donors under 50 years because of tissue elasticity; several advanced techniques now allow donor preparation from both cold and organ-cultured tissue in about 99% minimizing the risk of graft loss. Oversizing the area of Descemet's stripping in relationship to graft size enhances graft attachment and use of a standardized approach for graft delivery. Air bubble-driven nontouch unfolding techniques and, possibly, gas tamponade in the anterior chamber further enhance graft attachment and reduce surgery-induced endothelial cell loss. Graft orientation is made earlier by marking, slit beam and optical coherence tomography. Novel understanding of the functional anatomy of Descemet's membrane as well as migration of endothelial cells will allow to further refine DMEK and improve its outcome.

SUMMARY

Although the superiority of DMEK over Descemet's stripping automated endothelial keratoplasty in terms of safety and functionality had been further elucidated, remarkable progress has been made in the recent past regarding tissue preparation, insertion and intraoperative manipulation that will foster the more widespread use of DMEK among corneal surgeons.

Influence of preoperative donor tissue characteristics on graft dislocation rate after Descemet stripping automated endothelial keratoplasty

PURPOSE

To determine the influence of preoperative donor tissue characteristics on the graft dislocation rate after performing a Descemet stripping automated endothelial keratoplasty (DSAEK).

METHODS

We retrospectively analyzed the associations between donor tissue characteristics and graft dislocation rates for consecutive DSAEK surgeries performed in a 4-year period at a single institution.

RESULTS

From June 2007 to June 2011, 64 (18%) of 355 eyes underwent a procedure for graft dislocation. There were no differences in donor age, preoperative endothelial graft thickness, preprocessing endothelial cell density, change in endothelial cell density after processing, time from death to tissue processing, or time from tissue processing to surgery between eyes that experienced dislocations and those that did not (P > 0.05 for each). The graft recipient's corneal disease diagnosis, preoperative corneal thickness, preoperative visual acuity, glaucoma status, history of glaucoma surgery, and cataract surgery at the time of performing the DSAEK were not associated with an increased rate of dislocation (P > 0.05 for each). Recipients who experienced graft dislocation were significantly older (73.6 vs. 70.2 years, P = 0.03) and more likely to undergo subsequent repeat transplantation (29.7% vs. 10.7%, P < 0.0001).

CONCLUSIONS

We found no correlation between any corneal donor tissue characteristic and graft dislocation after the DSAEK was performed. Graft dislocation was more common in older recipients. Patients with dislocation had a higher rate of subsequent transplantation.