Survivability of locally prepared versus imported Descemet membrane endothelial keratoplasty grafts in Edmonton

OBJECTIVE

This study aimed to evaluate the long-term graft survivability of locally prestripped versus imported prestripped Descemet membrane endothelial keratoplasty (DMEK) grafts in Edmonton.

DESIGN

Prospective cohort study of patients who underwent DMEK surgery between January 1, 2020, and December 31, 2020.

PARTICIPANTS

All patients receiving a DMEK transplant during the study period in Edmonton.

METHODS

Two local technicians were trained to prestrip DMEK grafts in Edmonton. When available, local tissue was prestripped for DMEK surgery; otherwise, prestripped DMEK grafts were imported from an accredited American eye bank. Patient characteristics and DMEK graft characteristics and DMEK survivability were evaluated and compared between the 2 groups.

RESULTS

Thirty-two locally prestripped DMEK grafts and 35 imported prestripped DMEK grafts were used during the study period. Donor cornea characteristics and patient characteristics were similar between the 2 groups. Best-corrected visual acuity improved up to 6 months postoperatively and was 0.2 logMAR in the locally prestripped DMEK group and 0.2 logMAR in the imported DMEK group (p = 0.56). Rebubble rates were 25% in the locally prestripped DMEK group and 19% in the imported DMEK group (p = 0.43). There was 1 primary graft failure in each group (p = 0.93). Endothelial cell density decreased by 37% in the locally prestripped DMEK group and by 33% in the imported DMEK group 2 years after transplantation.

CONCLUSIONS

The long-term survivability of locally prepared DMEK grafts is comparable with that of DMEK grafts imported from American eye banks.

Long-Term Outcome After Bilateral Descemet Membrane Endothelial Keratoplasty for Fuchs Endothelial Corneal Dystrophy

PURPOSE

The aim of this study was to assess the long-term clinical outcome, complications, and graft survival of bilateral Descemet membrane endothelial keratoplasty (DMEK) in patients with Fuchs endothelial corneal dystrophy.

METHODS

This was a retrospective cohort study of 181 patients (362 eyes) with sequential bilateral DMEK for Fuchs endothelial corneal dystrophy. Clinical outcomes were assessed up to 5 years postoperatively. Outcome measures were best-corrected visual acuity, pachymetry, endothelial cell density, graft survival, and complication rates.

RESULTS

Contralateral DMEK was performed on average 15 ± 11 months (range: 2-60 months) after the first eye. From 1 until 5 years after DMEK, best-corrected visual acuity, pachymetry, endothelial cell density, and graft survival did not differ between the first and second eyes (all P > 0.05). Graft detachment occurred in 67 eyes (19% [18% first eyes, 19% second eyes], 6% bilateral), graft rejection in 9 eyes (3% [3% first eyes, 2% second eyes], 1% bilateral), glaucoma in 25 eyes (7% [8% first eyes, 6% second eyes], 2% bilateral), and graft failure in 22 eyes (6% [4% first eye, 8% second eye], 2% bilateral). All differences were not significant (all P > 0.05). Five-year graft survival rates were comparable for first and second eyes (0.95 and 0.92, respectively; P = 0.15).

CONCLUSIONS

Clinical outcomes after bilateral DMEK are similar in both eyes and sustainable in the longer term. Within the first 5 years, the same complication may rarely occur in the contralateral eye.

Quality and Agreement With Scientific Consensus of ChatGPT Information Regarding Corneal Transplantation and Fuchs Dystrophy

PURPOSE

ChatGPT is a commonly used source of information by patients and clinicians. However, it can be prone to error and requires validation. We sought to assess the quality and accuracy of information regarding corneal transplantation and Fuchs dystrophy from 2 iterations of ChatGPT, and whether its answers improve over time.

METHODS

A total of 10 corneal specialists collaborated to assess responses of the algorithm to 10 commonly asked questions related to endothelial keratoplasty and Fuchs dystrophy. These questions were asked from both ChatGPT-3.5 and its newer generation, GPT-4. Assessments tested quality, safety, accuracy, and bias of information. Chi-squared, Fisher exact tests, and regression analyses were conducted.

RESULTS

We analyzed 180 valid responses. On a 1 (A+) to 5 (F) scale, the average score given by all specialists across questions was 2.5 for ChatGPT-3.5 and 1.4 for GPT-4, a significant improvement ( P < 0.0001). Most responses by both ChatGPT-3.5 (61%) and GPT-4 (89%) used correct facts, a proportion that significantly improved across iterations ( P < 0.00001). Approximately a third (35%) of responses from ChatGPT-3.5 were considered against the scientific consensus, a notable rate of error that decreased to only 5% of answers from GPT-4 ( P < 0.00001).

CONCLUSIONS

The quality of responses in ChatGPT significantly improved between versions 3.5 and 4, and the odds of providing information against the scientific consensus decreased. However, the technology is still capable of producing inaccurate statements. Corneal specialists are uniquely positioned to assist users to discern the veracity and application of such information.

Visual function after ultrathin Descemet's stripping automated endothelial keratoplasty or Descemet's membrane endothelial keratoplasty combined with cataract surgery: a randomised controlled clinical trial

AIMS

To compare best-corrected visual acuity (BCVA), contrast sensitivity and endothelial cell density (ECD) after ultrathin Descemet's stripping automated endothelial keratoplasty (UT-DSAEK) and Descemet's membrane endothelial keratoplasty (DMEK).

METHODS

A randomised, single-blinded, single-centre design was used. 72 patients with Fuchs' endothelial dystrophy and cataract were randomised to UT-DSAEK or DMEK combined with phacoemulsification and lens implantation. 27 patients with cataract were included in a control group and treated with phacoemulsification and lens implantation. The primary outcome was BCVA at 12 months.

RESULTS

Compared with UT-DSAEK, DMEK resulted in better BCVA with mean differences of 6.1 early treatment diabetic retinopathy study (ETDRS) (p=0.001) after 3 months, 7.4 ETDRS (p<0.001) after 6 months and 5.7 ETDRS (p<0.001) after 12 months. The control group obtained significantly better BCVA with a mean difference of 5.2 ETDRS (p<0.001) compared with DMEK 12 months postoperatively. Compared with UT-DSAEK, contrast sensitivity was significantly better 3 months after DMEK with a mean difference of 0.10 LogCS (p=0.03). However, our study found no effect after 12 months (p=0.08). ECD was significantly lower after UT-DSAEK compared with DMEK with mean differences of 332 cells/mm2 (p<0.01) after 3 months, 296 cells/mm2 (p<0.01) after 6 months and 227 cells/mm2 (p=0.03) after 12 months.

CONCLUSIONS

Compared with UT-DSAEK, DMEK resulted in better BCVA 3, 6 and 12 months postoperatively. Twelve months postoperatively, DMEK had a higher ECD than UT-DSAEK; however, no difference in contrast sensitivity was found.

TRIAL REGISTRATION NUMBER

NCT04417959.

Outcomes and Early Complications Using an Endothelium-in Pull-Through Descemet Membrane Endothelial Keratoplasty Technique With Preloaded Versus Surgeon-Loaded Donor Tissue in Fuchs Patients

PURPOSE

This study aimed to compare outcomes and early complications using an endothelium-in pull-through Descemet membrane endothelial keratoplasty (DMEK) technique with preloaded versus surgeon-loaded donor tissue.

METHODS

Data from 163 eyes of 125 patients at the Wilmer Eye Institute diagnosed with Fuchs endothelial corneal dystrophy who underwent DMEK with or without cataract extraction using surgeon-loaded tissue (n = 83) or preloaded tissue (n = 80) were reviewed. Best-corrected visual acuity and early postoperative complications including small graft detachment (less than one third of the graft area), large graft detachment (more than one third), graft failure, and rebubbling were compared.

RESULTS

Baseline characteristics including age, sex, and visual acuity were not statistically different between the groups. Small graft detachment was observed in 18.1% of the surgeon-loaded and 22.5% of the preloaded group ( P = 0.48), whereas large detachment occurred in 12.0% and 5.0%, respectively ( P = 0.11). Among these, rebubbling was performed in 18 (21.7%) in the surgeon-loaded compared with 12 (15.0%) in the preloaded group ( P = 0.27). The rebubbling rate of the combined procedure (cataract surgery and DMEK) was 21.8% and of DMEK alone was 7.7% ( P = 0.048). Primary graft failure occurred in 2 surgeon-loaded cases (2.4%) and 1 preloaded case (1.3%) ( P = 0.58). There was no difference in postoperative best-corrected visual acuity at 1 year (logarithm of the minimum angle of resolution 0.21 ± 0.25 for the surgeon-loaded vs. 0.16 ± 0.16 for the preloaded group, P = 0.23).

CONCLUSIONS

DMEK surgery using preloaded endothelium-in tissue has comparable outcomes with surgeon-loaded endothelium-in tissue. However, there was a trend toward the lower rebubbling rate in DMEK alone compared with combined procedures.

Double trouble in DMEK surgery: Learning experience and review of the literature

PURPOSE

To report a challenging Descemet Membrane Endothelial Keratoplasty (DMEK) case, complicated by intraoperative aqueous misdirection and spontaneous anterior chamber fibrin reaction.

METHODS

A 70-year-old female affected by corneal edema due to Fuchs endothelial dystrophy underwent a triple procedure (cataract extraction - IOL implantation - DMEK surgery) in her left eye. This report illustrates the management of the intraoperative complications of aqueous misdirection syndrome and anterior chamber fibrin reaction.

RESULTS

Despite the optimal management of the posterior pressure and the thorough removal of the fibrinous reaction during the case, the DMEK graft was not completely unfolded and centred at the end of the surgical procedure. Nonetheless, the patient showed good long-term anatomical and functional recovery: at the last follow-up (2 years after surgery), central corneal thickness was 526 µm with a best corrected visual acuity of 20/25 and an endothelial cell density of 1112 cell/mm2.

CONCLUSION

Early recognition and prompt management of intraoperative aqueous misdirection syndrome and anterior chamber fibrin reaction during DMEK surgery is essential to ensure good functional and anatomical outcomes.

One-year Outcomes of Ultrathin Descemet Stripping Automated Endothelial Keratoplasty Combined with Cataract Surgery in the Korean Population

PURPOSE

To evaluate the refractive outcomes after ultrathin Descemet stripping automated endothelial keratoplasty (UT-DSAEK) combined with phacoemulsification and intraocular lens implantation (triple procedure) in the South Korean population.

METHODS

This retrospective observational study included 37 eyes of 36 patients who underwent the UT-DSAEK triple procedure between 2012 and 2021 in a single tertiary hospital. Preoperative and postoperative refractive outcomes and endothelial parameters at 1, 3, 6, and 12 months were observed.

RESULTS

At the final postoperative 12-month period, the average best-corrected visual acuity was 0.4 ± 0.5 in logarithm of the minimum angle of resolution. The mean endothelial cell density at 12 months was 1,841.92 ± 731.24 cells/mm2, indicating no significant endothelial cell loss compared to the baseline (p = 0.128). The mean postoperative central corneal thickness at 12 months was 597.41 ± 86.26 μm. The postoperative mean absolute error at 12 months was 0.96 ± 0.89 diopters (D) and mean error was 0.89 ± 0.97 D.

CONCLUSIONS

The results of our South Korean cohort study on UT-DSAEK triple surgery showed favorable and safe outcomes. Regardless of graft thickness, it should be noted that a hyperopic shift of 1.00 to 2.00 D needs to be considered in the case of UT-DSAEK triple surgery.

Retrospective Study of Preoperative Laser Peripheral Iridotomy Versus Intraoperative Surgical Peripheral Iridectomy in Descemet Membrane Endothelial Keratoplasty

PURPOSE

The aim of this study was to examine the outcomes of laser peripheral iridotomy (LPI) and surgical peripheral iridectomy (SPI) for Descemet membrane endothelial keratoplasty (DMEK) and DMEK with cataract extraction (triple DMEK).

METHODS

This retrospective interventional study included 135 eyes of 135 patients who underwent DMEK alone or triple DMEK. Primary outcomes were graft detachments necessitating rebubbling, repeat grafts, and pupillary block. The secondary outcomes included rejection, cystoid macular edema, uveitis, intraoperative hyphema, visual disturbances, and surgical time.

RESULTS

Thirty-one eyes in the LPI group and 104 eyes in the SPI group were included. Fifty-six eyes had DMEK alone, and 79 had triple DMEK. Visually significant graft detachments occurred in 7 of 31 eyes in the LPI group versus 19 of 104 eyes in the SPI group ( P = 0.61). No statistical significance in DMEK alone versus triple DMEK groups ( P = 0.61 vs. P > 0.99). Two patients in the LPI group and 5 in the SPI group required regraft ( P = 0.66). One (3.2%) experienced pupillary block compared with 5 (4.8%) ( P = 0.99) in the LPI and SPI groups, respectively. Secondary outcomes were similar in both groups ranging from 0% to 3% ( P > 0.99). None had visual disturbances. In DMEK alone, duration of surgery was significantly shorter in the LPI versus SPI group (32.8 vs. 44.1 minutes, P = 0.02).

CONCLUSIONS

This study demonstrated similar outcomes between LPI and SPI, although the LPI group had a shorter duration of surgery when DMEK was performed alone. The remainder of the outcomes demonstrated no statistically significant differences.

Different Course of Immune Reactions and Endothelial Cell Loss after Penetrating Low-Risk Keratoplasty and Descemet Membrane Endothelial Keratoplasty for Fuchs Endothelial Dystrophy

BACKGROUND

The aim of this study was to compare the incidence of immune reactions and endothelial cell loss after penetrating keratoplasty (PKP) vs. Descemet membrane endothelial keratoplasty (DMEK) in patients with Fuchs endothelial dystrophy (FED).

PATIENTS AND METHODS

In the present retrospective study, a total of 962 surgeries (225 excimer laser PKP and 727 DMEK) of 700 patients performed between 28.06.2007 and 27.08.2020 in the Department of Ophthalmology at Saarland University Medical Center UKS were statistically evaluated. On the one hand, the prevalence and the temporal course of the immune reactions that occurred were analysed using the Kaplan-Meier method, as well as the effect of the immune reactions on the endothelial cells and corneal thickness. Secondly, endothelial cell density, pleomorphism, and polymegethism of the endothelial cells were evaluated for the time points U1 = preoperative, U2 = 6 weeks postoperative, U3 = 6 to 9 months postoperative, U4 = 1 to 2 years postoperative, and U5 = 5 years postoperative. In addition, statistical tests were carried out for differences between the two types of surgery and in the longitudinal course.

RESULTS

A total of 54 immune reactions occurred during the observed period, whereby the probability of such a reaction was significantly greater in the PKP group with 8.9% than in the DMEK group with 4.5% (p = 0.011). The comparison of the two Kaplan-Meier curves also showed a significant difference between the two surgical techniques in the log-rank test (p = 0.012). The endothelial cell loss due to the immune reaction was only significant in PKP (p = 0.003). For all surgical procedures, endothelial cell density decreased significantly with time in both surgical techniques (p < 0.0001 in each case), but more strongly with DMEK than with PKP (p < 0.0001). Furthermore, this cell density was significantly higher with PKP than with DMEK for the whole observation time (p < 0.0001). Polymegethism decreased significantly in the DMEK group (p < 0.0001). Pleomorphism was significantly higher, on average, in DMEK than in PKP (p < 0.0001).

CONCLUSION

The prognosis of DMEK in patients with FED seems to be more favourable after immune reactions than that of PKP, as not only were immune reactions less frequent, but they were also milder. However, endothelial cell density was significantly higher in the PKP group during the entire follow-up.

Association Between Indication for Descemet Stripping Automated Endothelial Keratoplasty and Rural Residency

PURPOSE

Residing in rural locations can be a barrier to health care access. This study investigated the impact of residing in rural and small town (RST) areas on Descemet stripping automated endothelial keratoplasty (DSAEK) indications and outcomes in Atlantic Canada.

METHODS

A retrospective cohort analysis examined consecutive DSAEKs performed in Nova Scotia between 2017 and 2020. Patient rurality was determined by the Statistical Area Classification system developed by Statistics Canada. Univariate and multivariate logistic regression models were used to assess for factors associated with DSAEK indication, including repeat keratoplasty, RST residence status, and travel time.

RESULTS

Of 271 DSAEKs during the study period, 87 (32.1%) were performed on the eyes of RST residents. The median postoperative follow-up time was 1.6 years. Undergoing DSAEK for a previous failed keratoplasty was not associated with a higher odds of RST residency (odds ratio [OR], 0.50; 95% confidence interval [CI], 0.19-1.16; P = 0.13) but was associated with travel time (OR, 0.78 for each increasing hour of travel; 95% CI, 0.61-0.99; P = 0.044). RST residency was not associated with the occurrence of graft failure (OR, 0.48; 95% CI, 0.17-1.17; P = 0.13).

CONCLUSIONS

Residing in a rural area in Atlantic Canada was not associated with DSAEK graft failure. Repeat endothelial keratoplasty was associated with shorter travel time for corneal surgery but not rural residency status. Further research in this field could inform regional health strategies aimed at improving equity and accessibility to ophthalmology subspecialist care.

Combined or sequential DMEK in cases of cataract and Fuchs endothelial corneal dystrophy-A systematic review and meta-analysis

To compare the outcomes of Descemet membrane endothelial keratoplasty (DMEK) performed after phacoemulsification and intraocular lens (IOL) implantation (sequential DMEK) and DMEK combined with phacoemulsification and IOL implantation (combined DMEK) in patients with Fuchs endothelial corneal dystrophy (FECD) and cataract. Systematic literature review and meta-analysis performed according to the PRISMA guidelines and registered in PROSPERO. Literature searches were conducted in Medline and Scopus. Comparative studies reporting sequential DMEK and combined DMEK in FECD patients were included. The main outcome measure of the study was the corrected distance visual acuity (CDVA) improvement. Secondary outcomes were postoperative endothelial cell density (ECD), rebubbling rate and primary graft failure rate. Bias risk was assessed and a quality appraisal of the body of evidence was completed using the Cochrane Robin-I tool. A total of 667 eyes (5 studies) were included in this review, 292 eyes (43.77%) underwent a combined DMEK, while 375 (56.22%) eyes underwent a sequential DMEK surgery. We found no evidence of a difference between the two groups (mean difference, 95% CI) regarding: (1) CDVA improvement (-0.06; -0.14, 0.03 LogMAR; 3 studies, I2 : 0%; p = 0.86); (2) postoperative ECD (-62; -190, 67 cells/mm2 ; 4 studies, I2 : 67%; p = 0.35); (3) rebubbling (risks ratio: 1.04; 0.59, 1.85; 4 studies, I2 : 48%; p = 0.89); and primary graft failure rate (risks ratio: 0.91; 0.32, 2.57; 3 studies, I2 : 0%; p = 0.86). Of all the 5 non-randomized studies, all (100%) were graded as low quality. The overall quality of the analysed studies was low. Randomized controlled trials are needed to confirm no difference or superiority of one approach in terms of CDVA, endothelial cell count and postoperative complication rate between the two arms.

Comparison of Long-Term Outcomes of DSEK and DMEK in Fuchs Endothelial Dystrophy

PURPOSE

This study aimed to compare the long-term endothelial cell loss, graft survival, and clinical outcomes in patients with Fuchs endothelial dystrophy (FED) after Descemet stripping endothelial keratoplasty (DSEK) and Descemet membrane endothelial keratoplasty (DMEK) using a standardized surgical protocol.

METHODS

Three hundred and six consecutive DSEK and DMEK grafts of 223 patients with FED performed by 8 surgeons between January 2006 and August 2022 were analyzed. The primary outcome measures were graft survival, endothelial cell loss, and best spectacle-corrected visual acuity.

RESULTS

At 5 years, graft survival was 96% for both DSEK and DMEK eyes. The mean percentage of endothelial cell loss was 57.7 ± 17.1 in DSEK and 56.8 ± 15.2 in DMEK eyes ( P = 0.430). The mean best spectacle-corrected visual acuity was 0.13 ± 0.14 logMAR in DSEK and 0.01 ± 0.18 logMAR in DMEK grafts ( P <0.00001) at 5 years postoperatively. Rebubbling was performed in 7.8% DSEK and 2.1% DMEK grafts ( P = 0.441). Cox regression identified rejection episodes (HR 6.5; 95% CI: 1.70-24.8; P = 0.0062) as a significant contributing factor for graft failure.

CONCLUSIONS

DMEK had superior visual acuity outcomes compared with DSEK in these patients up to 5 years after surgery. At 5 years, there was no significant difference in graft survival or endothelial cell loss between DSEK and DMEK eyes with FED. We propose that our standardized technique reduces the need for rebubbling.

Emerging treatments for corneal endothelium decompensation - a systematic review

PURPOSE

Endothelial keratoplasty (EK) is the conventional treatment to improve visual acuity of corneal endothelium decompensation (CED) patients, with other therapies mainly for symptomatic relief. However, the shortage of corneal grafts and other limitations to EK urge the development of novel alternative treatments. In the last decade, novel options have been proposed, yet only a limited number of reviews have systematically reported on outcomes. Therefore, this systematic review evaluates the existing clinical evidence of novel surgical approaches for CED.

METHOD

We identified 24 studies that illustrated the clinical observations of the surgical approaches in interest. We included Descemet stripping only (DSO), Descemet membrane transplantation (DMT) where Descement membrane alone instead of corneal endothelium with cells is transplanted, and cell-based therapy.

RESULTS

In general, these therapies may provide visual outcomes comparable with EK under specific conditions. DSO and DMT target CED with relatively healthy peripheral corneal endothelium like Fuchs' corneal endothelial dystrophy, while cell-based therapy offers more versatile applications. Side effects of DSO would decrease with modifications to surgical techniques. Moreover, Rho-associated protein kinase inhibitor adjuvant therapy could enhance clinical results in DSO and cell-based therapy.

CONCLUSION

Long-term controlled clinical trials with larger sample size on the therapies are needed. The simplicity of DSO and the high translational potential of cell-based therapy to treat CED of most etiologies made these two treatment strategies promising.

Ten-Year Changes in Vision, Refractive Error, and Corneal Thickness After Descemet Stripping Automated Endothelial Keratoplasty for Fuchs Endothelial Corneal Dystrophy

PURPOSE

The goal of this study was to determine changes in best-corrected visual acuity (BCVA), refractive error, and central corneal thickness (CCT) during the first decade after Descemet stripping automated endothelial keratoplasty (DSAEK).

METHODS

Outcomes of all consecutive eyes undergoing DSAEK for Fuchs endothelial corneal dystrophy (FECD) were reviewed; eyes with untreatable comorbidities before DSAEK were excluded. DSAEK was performed through a temporal incision and all eyes were pseudophakic postoperatively. Changes in BCVA, manifest spherical equivalent, manifest cylinder (vector analysis), and CCT were assessed by using generalized estimating equation models.

RESULTS

BCVA improved between 6 months (0.18 ± 0.12 logarithm of the minimum angle of resolution (logMAR); Snellen equivalent, 20/30) and 5 years (0.10 ± 0.10 logMAR; 20/25; n = 74, P < 0.001) and then remained stable at 10 years (0.09 ± 0.10 logMAR, n = 48, P = 0.22). There was a myopic shift of -0.20 ± 0.51 D between 6 months and 5 years (n = 65, P = 0.002) that remained stable at 10 years (-0.09 ± 0.44 D; 20/25; n = 34, P = 0.33). Manifest cylinder drifted with-the-rule between 6 months and 5 years (n = 65, P < 0.001) and between 5 and 10 years (n = 34, P < 0.001). CCT was stable between 6 months (672 ± 57 μm) and 5 years (677 ± 55 μm, n = 67, P = 0.47), but increased at 10 years (702 ± 60 μm, n = 39, P = 0.001).

CONCLUSIONS

Excellent BCVA can be achieved during the first decade after DSAEK for FECD, although improvement seems to plateau after 5 years. Changes in manifest refractive error were not clinically significant. The gradual increase in CCT was consistent with longer-term changes found after other types of keratoplasty.

Corneal Guttae After Descemet Membrane Endothelial Keratoplasty

PURPOSE

The aim of this study was to report on the occurrence of corneal guttae after Descemet membrane endothelial keratoplasty (DMEK).

METHODS

In this retrospective case series, 13 eyes of 13 patients who underwent DMEK at 2 tertiary referral centers between 2007 and 2021 (average available follow-up 73 ± 52 months, range 18-174 months) and showed corneal guttae during postoperative examinations were included. Eye bank images were retrospectively reviewed.

RESULTS

Occurrence of guttae was observed by specular microscopy in 13 eyes. In 11 cases, presence of guttae was confirmed by confocal microscopy and in 1 case by histology. Five eyes showed an increase in guttae density during the postoperative course. Surgery indications were Fuchs endothelial corneal dystrophy (n = 11), pseudophakic bullous keratopathy (n = 1), and DMEK graft failure after allograft rejection (n = 1); the latter eye had shown no signs of guttae after primary DMEK. Two eyes with guttae required a repeat DMEK due to graft failure. At the last available follow-up, all 11 remaining eyes had clear corneas and 10 eyes had a best-corrected visual acuity of ≥0.9 (decimal). During donor cornea processing in the eye bank, no guttae were observed on the donor tissue.

CONCLUSIONS

Corneal guttae can occur after DMEK including in eyes operated for indications other than Fuchs endothelial corneal dystrophy and most likely guttae were present on the donor graft but were not detectable by routine slit-lamp and light microscopy evaluation in the eye bank. Postoperative guttae density varies among patients and especially small isolated guttae do not seem to affect clinical outcomes.

Comparison of efficacy of three gases for anterior chamber tamponade in Descemet's membrane endothelial keratoplasty

PURPOSE

To compare the efficacy of three different gases for intraocular tamponade: 100% air, 10% perfluoropropane (C3F8), and 10% sulfur hexafluoride (SF6), in Descemet's membrane endothelial keratoplasty (DMEK).

MATERIALS AND METHODS

The medical records of 138 patients who underwent DMEK were reviewed retrospectively, with the primary outcome being the rebubbling rate in the first week following surgery. Other clinical outcomes, such as best-corrected visual acuity (BCVA), central corneal thickness (CCT), incidence of rebubbling after the first week, endothelial cell density (ECD), graft detachment, graft failure, pupillary block, and intraocular pressure (IOP) changes were also analyzed.

RESULTS

Of the 138 patients, 57 were in group 1 (treated with air), 44 in group 2 (treated with 10% C3F8), and 37 in group 3 (treated with 10% SF6). Group 3 showed significantly lower rates of graft detachment and rebubbling compared to groups 1 and 2 (P<0.001). However, there was no significant difference in postoperative BCVA among the groups. At one year, the mean endothelial cell loss was 32% in group 1, 30% in group 2, and 33% in group 3 (P=0.715). One patient in group 1 experienced pupillary block and increased IOP, while there were no such occurrences in the other groups. There was no difference between the groups in terms of graft failure.

CONCLUSION

The use of 10% SF6 in DMEK surgery may be a good option due to its efficacy in preventing graft detachment, low rebubbling rate, and potential for minimizing complications.

Descemet Endothelial Thickness Comparison Trial 1 (DETECT 1): outcome masked, placebo-controlled trial comparing two types of corneal transplant surgeries and effect of rho kinase inhibitors on endothelial cell loss protocol

BACKGROUND

It remains uncertain which endothelial keratoplasty (EK) technique yields the best outcomes while maintaining safety, particularly in eyes with coexisting ocular conditions. Moreover, the impact of endothelial cell loss (ECL) on long-term graft survival requires further investigation. Adjuvant ripasudil, a rho kinase inhibitor, may address the challenge of ECL in corneal transplantation. This paper presents the protocol for the Descemet Endothelial Thickness Comparison Trial 1 (DETECT 1), a multicentre, outcome-masked, randomised, placebo-controlled, four-arm clinical trial.

METHODS

A total of 160 eligible patients with endothelial dysfunction will be enrolled from five participating sites in the USA. The patients will be randomly assigned in a 2×2 factorial design to one of the following treatment groups: group 1-ultrathin Descemet stripping endothelial keratoplasty (UT-DSAEK) plus topical ripasudil 0.4%; group 2-UT-DSAEK plus topical placebo; group 3-Descemet membrane endothelial keratoplasty (DMEK) plus topical ripasudil 0.4% and group 4-DMEK plus topical placebo. Primary outcomes include the best spectacle-corrected visual acuity at 12 months and ECL at 12 months. Secondary outcomes include visual acuity at different time points, vision-related quality of life, endothelial cell morphology and cost-effectiveness.

RESULTS

The study outcomes will be analysed using mixed effects linear regression models, taking into account the treatment arms and relevant covariates. Adverse events, including rebubble procedures, graft failure and graft rejection, will be documented and analysed using appropriate statistical methods.

CONCLUSION

DETECT I aims to provide evidence on the comparative effectiveness of UT-DSAEK and DMEK, as well as the potential benefits of adjuvant topical ripasudil in reducing ECL. The results of this trial will contribute to optimising corneal transplantation techniques and improving long-term graft survival, while also exploring the cost-effectiveness of these interventions. Dissemination of findings through peer-reviewed publications and national/international meetings will facilitate knowledge translation and guide clinical practice in the field of corneal transplantation.

ETHICS AND DISSEMINATION

A data and safety monitoring committee (DSMC) has been empaneled by the NEI.All study protocols will be subject to review and approval by WCG IRB as the single IRB of record.This study will comply with the National Institute of Health (NIH) Data Sharing Policy and Policy on the Dissemination of NIH-Funded Clinical Trial Information and the Clinical Trials Registration and Results Information Submission rule. Data from the trial will be made available on reasonable request.

The outcomes of postoperative eye patching after cataract surgery in patients with Fuchs' endothelial corneal dystrophy

PURPOSE

To investigate the influence of post-operative eye patching on corneal thickness, endothelial cells' loss and visual acuity in patients diagnosed Fuchs' endothelial corneal dystrophy (FECD).

SETTING

Public healthcare centre, Shamir Medical Centre, Israel.

METHODS

This randomized controlled trial included patients with FECD undergoing routine cataract surgery in a public medical centre. Patients were randomly assigned to 2 groups: the eye undergoing surgery was covered with a patch for 24 h in the first group (patched group), and a plastic shield was used in the second (non-patched group). Both groups received a unique dose of a local steroid and antibiotic post-operatively. The eyes were examined pre-operatively, and on days 1, 7 and 30 post-surgery . Examination included: best corrected visual acuity (BCVA), comeplete slit lamp examination, intra ocular pressure (IOP), anterior chamber depth (ACD), central corneal thickness (CCT) using the IOL Master 700 (Zeiss, Germany) and endothelial cell density (ECD) using Specular microscopy. Cumulative dissipated energy (CDE) and operation time were recorded for all cases.

RESULTS

The study included 46 eyes of 46 patients diagnosed with FECD. Twenty-three eyes in the patched group, and 23 eyes in the non-patched group . Thirty days post-operatively the CCT in the patched group decreased by 60 ± 38 mµ (9%) compared to 92 ± 80 mµ (13.5%) in the non- patched group (p = 0.04). Seven days post-operatively the CCT in the patched group decreased by 31 ± 35 mµ (5%) compared to 58 ± 76 (8%) in the non-patched group, but this difference did not reach statistical significance (p = 0.081). There was no statistically significant difference in endothelial cells loss as well as BCVA at 1, 7 and 30 days post-operatively between the study groups.

CONCLUSIONS

Avoiding eye patch post-operatively after cataract surgery in patients with FECD results in better corneal clarity recovery and reduced corneal edema one month post-operatively. Visual acuity and endothelial cell's loss were not influenced by patching.

New forceps free injection technique for delivering descemet membrane endothelial keratoplasty preloaded endothelium-in grafts

PURPOSE

To describe a new method for delivering DMEK grafts into the recipient's eye with endothelium inward configuration using a no-forceps injection technique.

METHODS

We retrospectively review 11 patients that underwent DMEK surgery at our institution using a no-forceps injection technique. The graft was preloaded into an intraocular lens (IOL) cartridge and connected to an anterior chamber maintainer (ACM). A 5 ml non luer lock syringe was inserted into the other end of the ACM to create a one-flow system. The cartridge was inserted into the posterior end of an injector, and the graft was successfully delivered into the recipient's eye.

RESULT

Twelve eyes of 11 patients were included. Mean follow-up was 9.16 ± 1.3 months. At baseline, mean best corrected visual acuity (BCVA) was 0.76 ± 0.13 logMAr and mean endothelial cell density (ECD) was 2619.00 ± 115.89 cells/mm2. At follow-up, BCVA significantly improved to 0.22 ± 0.05 logMAR (p = 0.003). Although we observed a significant reduction in ECD at follow-up (1688 ± 182.20, p = 0.002), our patients lost only 35.69 ± 6.36% of endothelial cells.

CONCLUSION

Our technique can help surgeons safely deliver an endothelium-in graft into the recipient's eye. The method doesn't require the use of a forceps, minimizing the risk of endothelial cell loss or graft damage.

Preloaded DMEK With Endothelium Outward: A Multicenter Clinical Study Using DMEK Rapid Device

PURPOSE

The objective of this study is to validate Descemet membrane endothelial keratoplasty (DMEK) Rapid device for preloading DMEK grafts with endothelium outward.

METHODS

In this multicenter retrospective clinical study, DMEK tissues (n = 27) were peeled and preloaded (8.25 mm) in a DMEK Rapid device. The device was loaded in a container prefilled with the storage solution and shipped from a single center in Italy to 4 different centers located in Italy and the United Kingdom. Preloaded tissues were delivered by injecting the graft in the anterior chamber. Patients were monitored at days 1 and 15 and at months 1, 3, and 6, as well as at the last follow-up (9-12 months) postoperatively. Main outcome measures included rebubbling rate and graft failure, corrected distance visual acuity, endothelial cell loss (ECL), and central corneal thickness at all time points. A one-way analysis of variance test comparing day 1 with all later time points was followed with significance at P < 0.05.

RESULTS

The average recorded surgical time was 6 to 25 minutes with no immediate surgical complications. Rebubbling was observed in 7 of 26 cases with one graft failure within 15 days postoperatively. The mean corrected distance visual acuity at day 1 was 0.64 ± 0.49 logMAR, which improved to 0.18 ± 0.43 logMAR at the last follow-up. Endothelial cell density values showed a significant decrease at the last follow-up (1827 ± 565 cells/mm 2 ) ( P < 0.001) compared with the preoperative value (2503 ± 128 cells/mm 2 ), with an average endothelial cell loss of 27%. Central corneal thickness significantly dropped from 694 ± 157 μm at day 1 to 502 ± 42 μm at the last follow-up ( P < 0.001).

CONCLUSIONS

DMEK Rapid device is quick, easy, and efficient for preloading and shipping DMEK grafts internationally in endothelium-outward orientation.

The surgical management of a patient with Fuchs endothelial dystrophy and cataracts

Objective: To report the two different surgical approaches in the case of a patient with Fuchs endothelial dystrophy with low endothelial cell count and advanced cataracts. Methods: The chosen surgical approach differed between eyes, with the right eye undergoing a combined approach consisting of cataract surgery, intraocular lens implantation, and penetrating keratoplasty in 2022. One year later, for the left eye, a different approach was decided: cataract surgery followed by Descemet membrane endothelial keratoplasty (DMEK). The Descemet membrane graft was prepared by the surgeon using the liquid bubble technique. AS-OCT was used to monitor the patient before and after surgery. Results: Visual recovery was excellent for both eyes, however, visual acuity improved quickly in the left eye (DMEK), while, in the right eye (PK), the best corrected visual acuity was reached after several months post-surgery. Conclusion: Advanced stages of Fuchs dystrophy patients will most likely need corneal transplantation. Each type of corneal transplantation procedure comes with unique challenges, both intraoperative and postoperative. DMEK is a very good treatment option for patients with Fuchs endothelial dystrophy, with excellent visual recovery and good graft survival at the 10-year mark. Abbreviations: DMEK = Descemet membrane endothelial keratoplasty, PK = penetrating keratoplasty, AS-OCT = anterior segment optical coherence tomography, FECD = Fuchs endothelial corneal dystrophy, BCVA = best corrected visual acuity, US = ultrasound, CDE = cumulative dissipated energy, IOL = intraocular lens.

Effect of Simultaneous Endothelial Keratoplasty and Cataract Surgery: A Secondary Analysis of the Descemet Endothelial Thickness Comparison Trial

PURPOSE

Combining cataract surgery with endothelial keratoplasty (triple EK) is a common practice and may be safer because it commits the patient to only one surgery. This study aimed to determine whether outcomes of pseudophakic endothelial keratoplasty and triple EK have similar outcomes.

METHODS

This was a non-prespecified secondary analysis of a multicenter, double-masked, randomized, controlled clinical trial. Enrollment centers included the Casey Eye Institute at Oregon Health and Sciences University and the Byers Eye Institute at Stanford University. Patients with damaged or diseased endothelium and were considered good candidates for either Descemet membrane endothelial keratoplasty or ultrathin Descemet stripping automated endothelial keratoplasty were randomized to one of the two surgeries 1-2 days prior to surgery. If the patient had a cataract, they underwent simultaneous cataract surgery. The primary outcome was visual acuity at 6 months. Visual acuity at 3, 12, and 24 months, 3, 6, 12, and 24 month endothelial cell density and intraoperative and postoperative complications were also recorded.

RESULTS

Those who had pseudophakic EK generally were older, more likely to be male, and more likely to have worse baseline vision with higher corneal densitometry values. After controlling for baseline visual acuity and type of keratoplasty, those that underwent Triple-EK had 0.09 better LogMAR lines better visual acuity at 6 (95% CI -0.17 to -0.10; P = 0.02) and 12 months (95% CI -0.21 to -0.07; P = 0.03). Although those receiving Triple- EK had nearly one-half LogMAR line better visual acuity at 24 months, it was no longer statistically significant (95% CI -0.20 to -0.05; P = 0.36). There was no statistically significant difference in ECD between groups at any timepoint. Those undergoing triple EK were more likely to have at least one adverse event (P = 0.02).

CONCLUSIONS

Earlier intervention with Triple-EK may improve visual acuity outcomes after endothelial keratoplasty compared with staged procedures, but may also increase the risks of adverse events including the need for re-bubble.

Persistent Localized Descemet Membrane Endothelial Keratoplasty Detachments Secondary to Corneal Ink Stain Marks

PURPOSE

The aim of this study was to describe 2 cases of persistent endothelial graft detachments secondary to corneal gentian violet ink stain marks.

METHODS

This study included a case review of hospital records of 2 eyes with localized Descemet's membrane detachments after Descemet membrane endothelial keratoplasty (DMEK) surgery.

RESULTS

Two patients underwent consecutive uncomplicated DMEK surgery for Fuchs endothelial dystrophy with identical techniques. The grafts were marked with an ink marker through a stromal window to ensure correct orientation during donor graft preparation. Both patients had localized detachments around the ink mark on day 1, week 1, and up to 1 month at postoperative review. The persistent detachment was believed to be due to the gentian violet marker used which had a higher concentration of isopropyl alcohol solvent than the standard marking pen routinely used.

CONCLUSIONS

Ink markers with higher concentrations of isopropyl solvent may result in higher DMEK detachment rates and caution is advised when using these markers.

[Outcomes of hemi-Descemet membrane endothelial keratoplasty and phacoemulsification for the treatment of primary Fuchs' endothelial corneal dystrophy combined with cataract]

PURPOSE

This study evaluates the long-term results of surgical treatment of patients with Fuchs' endothelial corneal dystrophy and cataract.

MATERIAL AND METHODS

The study included 24 patients (24 eyes) with primary Fuchs' endothelial corneal dystrophy and cataract, who underwent cataract phacoemulsification with IOL implantation and of Descemet's membrane endothelial keratoplasty with a semicircular graft (hemi-DMEK). The effect of treatment was assessed by best corrected visual acuity (BCVA), central corneal thickness (CCT) and endothelial cell density (ECD).

RESULTS

In total, surgical treatment involved 14 donor corneas that were divided in half during the preparation and isolation of the Descemet's membrane (DM). By month 12 after the surgery an increase in visual functions and graft transparency were observed in 23 patients (23 eyes) out of 24. Repeated keratoplasty was required in one case due to fibrosis of the posterior layers of recipient's corneal stroma. At 12 months postoperatively, the study group showed an increase in BCVA from 0.16±0.1 to 0.75±20, a decrease in CCT from 650.9±4.5 μm to 519.6±43.9, and a decreased in ECD from 2850.5±84.7 cells/mm2 up to 1285.5±277.2 cells/mm2. Thus, the loss of endothelial cells at one year after surgery amounted to 54.9%.

CONCLUSIONS

The developed method for transplantation of a semicircular DM fragment provides a tissue-saving approach to endothelial keratoplasty, and considering the high percentage of transparent engraftment of grafts and complete visual rehabilitation, it can be recommended in the treatment of patients with cataract and Fuchs' endothelial corneal dystrophy.

Role of Direct Supervision in the Learning Curve of Descemet Membrane Endothelial Keratoplasty Surgery

PURPOSE

The aim of this study was to compare complication rates of Descemet membrane endothelial keratoplasty (DMEK) performed by directly supervised and nondirectly supervised corneal fellows.

METHODS

This study was a retrospective, comparative case series of DMEK surgeries performed by novice surgeons (less than 15 DMEK cases) with or without direct direct expert supervision. Patients who underwent surgery for Fuchs endothelial dystrophy or pseudophakic bullous keratopathy with a minimum follow-up of 12 weeks were included. Data on patients' demographics, surgical details, surgeon level, intraoperative and postoperative complications, and rate of rebubbling were collected.

RESULTS

In this study, 41 nondirectly supervised and 48 directly supervised DMEK surgeries were included. At 6 months, 67.4% of eyes achieved a best-corrected visual acuity of ≤0.3 logMAR with no significant difference between groups ( P = 0.95). Intraoperative complications occurred in 22% of cases in the nondirect supervision group and 4.2% in the direct supervision group ( P = 0.02). Postoperative complications occurred in 9.8% of cases in the nondirect supervision group and 6.2% of cases in the direct supervision group ( P = 0.7). The rebubbling rate was comparable in the 2 groups (34.1% vs. 33.3%, P = 1.0). Five cases (12.2%), all from the nondirect supervision group, required secondary keratoplasty ( P = 0.02). The overall complication rate was significantly higher in the nondirect supervision group (31.7% vs. 10.4%, P = 0.03).

CONCLUSIONS

Functional success can be achieved in directly supervised or nondirectly supervised DMEK surgery. However, nondirectly supervised DMEK surgery may associate with higher rates of complications.

Identification and Analysis of Primary Cilia in the Corneal Endothelial Cells of Patients with Bullous Keratopathy

PURPOSE

To identify primary cilia in human corneal endothelial cells (CECs) obtained from patients with bullous keratopathy (BK).

METHODS

This study involved CEC specimens obtained from 10 eyes of 10 consecutive patients (three males and seven females; mean age: 74.5 years, range: 68-90 years) with BK who underwent Descemet's stripping automated endothelial keratoplasty at Baptist Eye Institute, Kyoto, Japan between August 2019 and September 2020. Three corneal buttons obtained from 3 patients who underwent penetrating keratoplasty for keratoconus were used as 'non-BK' controls. All specimens were evaluated with immunofluorescence staining using an antibody against acetylated α-tubulin.

RESULTS

Ciliary expression was observed in six of the 10 CEC specimens; i.e. in two specimens obtained from BK patients after glaucoma surgery (trabeculectomy), in two specimens obtained from patients with Fuchs endothelial corneal dystrophy, and in two specimens obtained from a patient with BK after laser iridotomy for primary angle closure. There was acetylated α-tubulin staining but no hair-like structures in two specimens, and ciliary expression was unknown in two specimens due to the absence of cells. The length of the primary cilia varied between all specimens. In contrast, no primary cilia were observed in the corneal buttons obtained from the three keratoconus patients.

CONCLUSION

The findings in this study clearly demonstrate the expression of primary cilia in the CECs of patients afflicted with BK.

Five-year clinical outcomes of 107 consecutive DMEK surgeries

PURPOSE

The long-term clinical outcomes, postoperative complications, and graft survival of Descemet-membrane endothelial keratoplasty (DMEK) remain poorly understood. We retrospectively assessed these variables in all consecutive eyes that underwent DMEK for any indication in 2014-2018. The findings were compared to the long-term DMEK studies of five other groups (3-10-year follow-up).

METHODS

Patients underwent ophthalmological tests preoperatively, at 1, 3, 6, and 12 postoperative months, and then annually. Five-year graft survival was determined by Kaplan-Meier estimator. Change in best-corrected visual acuity (BCVA), endothelial-cell density (ECD), and central-corneal thickness (CCT) at each timepoint was determined.

RESULTS

107 eyes (80 patients; 72 years old; 67% female) underwent first-time DMEK for uncomplicated Fuchs endothelial corneal dystrophy (94% of eyes), pseudophakic bullous keratopathy (3%), and regraft after previous keratoplasty (3%). The most common complication was graft detachment requiring rebubbling (18%). Thirteen grafts (12%) failed at ≤15 months. Cumulative 5-year graft-survival probability was 88% (95% confidence intervals = 79-94%). BCVA improved from 0.6 logMAR preoperatively to 0.05 logMAR at 1 year (p<0.0001) and then remained stable. Donor ECD dropped by 47% at 6 postoperative months and then continued to decrease by 4.0%/year. Five-year endothelial-cell loss was 65% (from 2550 to 900 cells/mm2). CCT dropped from 618 to 551 μm at 5 years (p<0.0001). These findings are generally consistent with previous long-term DMEK studies.

CONCLUSIONS

DMEK has low complication and high graft-survival rates and excellent clinical outcomes that persist up to 5 years post-surgery. DMEK seems to be a safe and effective treatment in the long term.

Macular Thickness After Ultrathin Descemet Stripping Automated Endothelial Keratoplasty and Descemet Membrane Endothelial Keratoplasty Combined With Cataract Surgery: A Randomized Controlled Clinical Trial

PURPOSE

The aim was to investigate alterations in central retinal thickness (CRT) and their implications for visual acuity after ultrathin Descemet stripping automated endothelial keratoplasty (UT-DSAEK) and Descemet membrane endothelial keratoplasty (DMEK) combined with cataract surgery.

METHODS

A total of 72 eyes of 72 patients with Fuchs endothelial dystrophy and cataract were included and equally randomized to either UT-DSAEK or DMEK. A control group of 40 eyes of 40 patients with cataract were included for cataract surgery. All participants were examined preoperatively as well as 3 and 6 months postoperatively.

RESULTS

There was no significant difference in CRT between the study groups after surgery ( P = 0.896). A significant difference in best-corrected visual acuity (BCVA) progression over time was found between the study groups ( P < 0.0001). Average improvements of 8.03 EDTRS after UT-DSAEK ( P < 0.001) and 16.77 EDTRS after DMEK ( P < 0.001) were found 6 months postoperatively. No significant correlation was found between the change in BCVA and CRT from baseline to 3 months postoperatively (r 2 < 0.0001, P = 0.96) and from baseline to 6 months postoperatively (r 2 = 0.0053, P = 0.46).

CONCLUSIONS

CRT was not altered by UT-DSAEK, DMEK, or cataract surgery 3 and 6 months postoperatively. BCVA significantly improved 3 and 6 months after UT-DSAEK and DMEK, respectively. No significant correlations were found between the change in BCVA and CRT postoperatively. As such CRT alterations were comparable after UT-DSAEK, DMEK, and cataract surgery.

Clinical Outcomes of Transscleral-Sutured Intraocular Lens Combined With Descemet Membrane Endothelial Keratoplasty

PURPOSE

The aim of the study was to report clinical outcomes of Descemet membrane endothelial keratoplasty (DMEK) combined with transscleral-sutured intraocular lens (IOL) compared with DMEK combined with phacoemulsification and posterior chamber IOL (Phaco-DMEK).

METHODS

A retrospective chart review of all patients who underwent DMEK combined with transscleral-sutured intraocular lens fixation or combined with phacoemulsification for Fuchs endothelial corneal dystrophy from 2016 to 2021 at the Toronto Western Hospital or the Kensington Eye Institute (Toronto, ON, Canada) and had at least 18 months of follow-up was performed. Main outcomes were postoperative distance-corrected visual acuity, rebubbling rate, graft survival rate, and complications.

RESULTS

Twenty-one cases of DMEK combined with transscleral-sutured IOL (DMEK-TSS-IOL) and 44 cases of Phaco-DMEK were evaluated. Twelve eyes (57.15%) had a foldable acrylic 3-piece IOL (AR40E) and 9 (42.85%) had a single-piece polymethylmethacrylate (PMMA) IOL (CZ70BD). LogMAR distance-corrected visual acuity improved significantly from 1.48 ± 0.62 (SD) to 0.86 ± 0.82 ( P = 0.01) 12 months after DMEK-TSS-IOL and from 0.41 ± 0.29 logMAR to 0.11 ± 0.11 logMAR ( P < 0.0001) after Phaco-DMEK. No statistically significant differences were observed in donor ( P = 0.97) or 1-year postoperative endothelial cell density ( P = 0.11) between the groups. Rebubbling was necessary in 33.33% of eyes in DMEK-TSS-IOL compared with 25% of Phaco-DMEK eyes ( P = 0.55). Graft survival rate was 76.19% in the DMEK-TSS-IOL group compared with 90.90% in the Phaco-DMEK group ( P = 0.13).

CONCLUSIONS

Transscleral-sutured IOL combined with DMEK is an option for the management of endothelial diseases in aphakic eyes or those which require IOL exchange for the experienced surgeon. However, when compared with routine Phaco-DMEK, there are higher complication and lower survival rates at 18 months.

Descemet Stripping Automated Endothelial Keratoplasty versus Descemet Membrane Endothelial Keratoplasty for Fuchs Endothelial Corneal Dystrophy: A National Registry-Based Comparison

PURPOSE

To compare the outcome between posterior lamellar corneal transplant procedures for Fuchs endothelial corneal dystrophy, taking preoperative patient characteristics in consideration. Surgical methods compared were Descemet membrane endothelial keratoplasty (DMEK), Descemet stripping automated endothelial keratoplasty (DSAEK), and DSAEK with concomitant cataract surgery (phacoemulsification plus DSAEK).

DESIGN

Registry-based study with propensity score matching.

PARTICIPANTS

One thousand six hundred seventy-seven patients from all Swedish corneal transplantation units treated from 2012 through 2019.

METHODS

All patients undergoing endothelial keratoplasty performed from 2012 through 2019 with completed 2-year follow-up data reported to The Swedish Corneal Transplant Register were included, totaling 1677 patients. Three comparable groups (DMEK, DSAEK, and phacoemulsification plus DSAEK) with 216 patients in each group were generated with propensity score matching based on preoperative visual acuity, age, sex, year of surgery, and preoperative risk factors such as inflammation, vascularization, and glaucoma.

MAIN OUTCOME MEASURES

Best-corrected visual acuity (BCVA) at the 2-year follow-up, frequency of graft dislocation, graft rejection episodes, and graft failure within 2 years including primary graft failure.

RESULTS

The preoperative corneal status was affected more severely in the DSAEK group before matching. In the matched groups, the median BCVA 2 years after surgery was 0.1 logarithm of the minimum angle of resolution (logMAR) in both the DMEK and the phacoemulsification plus DSAEK groups and 0.15 logMAR in the DSAEK group (P = 0.001). The frequency of graft dislocation was higher among the patients undergoing phacoemulsification plus DSAEK, but the frequency of graft failure and primary graft failure was higher in the DMEK group.

CONCLUSIONS

Visual acuity improved in most patients (90%) with all 3 surgical methods. However, DMEK and phacoemulsification plus DSAEK reached higher levels of visual acuity 2 years after surgery, and phacoemulsification plus DSAEK was superior considering graft survival rate. All 3 surgical procedures showed both strengths and weaknesses, suggesting that the choice of surgical method should be individualized, taking into consideration not only the cornea, but each patient's complete medical status as well as the entire course of postoperative medical care.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Comparison of repeat penetrating keratoplasty, DSAEK and DMEK for the management of endothelial failure of previous PK

PURPOSE

To compare the clinical outcomes of repeat PK, DSAEK-on-PK or DMEK-on-PK for the management of endothelial failure of previous penetrating keratoplasty.

DESIGN

Retrospective, interventional consecutive case series.

PARTICIPANTS

104 consecutive eyes of 100 patients requiring a second keratoplasty for endothelial failure of their primary penetrating keratoplasty performed between September 2016 and December 2020.

INTERVENTION

Repeat keratoplasty.

MAIN OUTCOME MEASURES

Survival and visual acuity at 12 and 24 months, rebubbling rate and complications.

RESULTS

Repeat PK was performed in 61/104 eyes (58.7%), DSAEK-on-PK was performed in 21/104 eyes (20.2%) and DMEK-on-PK was performed in 22/104 eyes (21.2%). Failure rates in the first 12 and 24 months were 6.6% and 20.6% for repeat PKs compared to 19% and 30.6% for DSAEK and 36.4% and 41.3% for DMEK. For those grafts surviving 12 months, the chances of surviving to 24 months were greatest for DMEK-on-PK at 92% vs 85% each for redo PK and DSAEK-on-PK. Visual acuity at one year was logMAR 0.53 ± 0.51 in the redo PK group, 0.25 ± 0.17 for DSAEK-on-PK and 0.30 ± 0.38 for DMEK-on-PK. 24-month outcomes were 0.34 ± 0.28, 0.08 ± 0.16, and 0.36 ± 0.36 respectively.

CONCLUSIONS

DMEK-on-PK has a greater failure rate in the first 12 months than DSAEK-on-PK which has a greater failure rate than redo PK. However, the 2-year survival rates in our series for those already surviving 12 months were greatest for DMEK-on-PK. There was no significant difference in visual acuity at 12 or 24 months. Careful patient selection is needed by experienced surgeons to determine which procedure to offer to patients.

Descemet membrane endothelial keratoplasty combined with presbyopia-correcting and toric intraocular lenses - a narrative review

Fuchs endothelial corneal dystrophy (FECD) is the leading indication for EK and may coexist with cataract and presbyopia. Notably, the outcomes of phacoemulsification in FECD patients are not as favorable as those in eyes without this condition. Historically, only monofocal intraocular lenses (IOLs) were recommended for these patients. However, recent reports have described the implantation of Premium-IOLs (such as Multifocal IOLs, Enhanced Depth of Focus IOLs, and Toric IOLs) in FECD eyes undergoing cataract surgery and Descemet membrane endothelial keratoplasty (DMEK). While the results are encouraging, they are not as optimal as those from unoperated eyes, especially when comparing simultaneous procedures to sequential ones. It's advised to perform the DMEK first to improve the accuracy of IOL calculations. Still, even successfully operated eyes may experience secondary graft failure or graft rejection after DMEK. The success rate of a secondary DMEK is typically lower than that of the initial procedure. Furthermore, if the postoperative thickness after DMEK is less than anticipated, laser enhancements might not be an option. There's a pressing need for more controlled and randomized clinical trials to ascertain the safety and effectiveness of Premium-IOLs for FECD eyes. This narrative review aims to collate evidence on the use of Premium IOL technologies in eyes receiving EK and to underscore key points for surgeons performing EK combined with cataract surgery.

Safety and clinical outcomes of omitting same and next day review after DMEK performed with an inferior peripheral iridotomy

BACKGROUND/OBJECTIVES

To determine the incidence of day one postoperative complications after Descemet Membrane Endothelial Keratoplasty (DMEK) performed with intraoperative inferior peripheral iridotomy (PI), and whether their early detection influences postoperative intervention.

SUBJECTS/METHODS

70 eyes of 70 consecutive patients that underwent DMEK from August 2019 to August 2021 at a single UK centre were retrospectively analysed. Cases that did not have an inferior PI were excluded. Any action taken at day one and week one postoperative review was noted.

RESULTS

No pupil block or other major adverse events were found at day one review. At one week, 14 eyes (20%) required re-bubbling, all of which had been fully attached at the day one review.

CONCLUSIONS

This series suggests that inferior PI performed alongside DMEK alone or triple DMEK effectively minimizes the risk of pupil block. Since no early complications occurred in this cohort requiring immediate intervention, it may be safe to defer review of these patients to a later time point.

Descemet membrane endothelial keratoplasty compared with ultrathin Descemet stripping automated endothelial keratoplasty: a meta-analysis

AIMS

This study aims to compare the clinical outcome of Descemet membrane endothelial keratoplasty (DMEK) and ultrathin Descemet stripping automated endothelial keratoplasty (UT-DSAEK) in patients with corneal endothelial dysfunction due to Fuchs' endothelial dystrophy or pseudophakic bullous keratopathy.

METHODS

We conducted a meta-analysis using a literature search of Embase, PubMed, Cochrane CENTRAL, ClinicalTrials.gov and WHO ICTRP databases. We included randomised controlled trials (RCTs) and cohort studies that compared DMEK and UT-DSAEK (graft<130 µm), with a follow-up of ≥12 months, published until 20 February 2022. We used the Revised Cochrane risk-of-bias tool for RCTs and the Risk of Bias in Non-Randomised Studies-of Interventions system for cohort studies.

RESULTS

Out of 144 records, 8 studies (3 RCTs, 2 fellow-eye studies and 3 cohort studies) were included, encompassing 376 eyes, (N=187 DMEK vs N=189 UT-DSAEK). The 12-month logarithm of the minimum angle of resolution best-corrected visual acuity (BCVA) was better post-DMEK (mean difference -0.06 (95% CI -0.10 to -0.02)), but with higher rebubbling risk: OR 2.76 (95% CI 1.46 to 5.22). Heterogeneity was significant I2=57%. Findings were consistent when excluding retrospective studies, including only studies with low risk of bias or RCTs only. An analysis of studies with mean DSAEK grafts <70 µm showed no significant difference in BCVA between the procedures. Publication bias was found in the BCVA analysis (Egger's test p=0.023).

CONCLUSIONS

Post-DMEK BCVA is superior to post-UT-DSAEK when using <130 µm grafts. DSAEK grafts <70 µm may not significantly differ from DMEK. The higher risk of rebubbling with DMEK necessitates an appropriate selection of patients.

PROSPERO REGISTRATION NUMBER

CRD42022340805.

12-year follow-up of the first endothelial keratoplasty without Descemet stripping in a 3-month newborn with Congenital Hereditary Endothelial Dystrophy (CHED)

BACKGROUND

Endothelial Keratoplasty (EK) is now considered as the standard treatment for Congenital Hereditary Endothelial Dystrophy (CHED) by many surgeons. We present the 12-year clinical outcome of the youngest operated patient with CHED in which we successfully performed a bilateral EK procedure without removing the recipient endothelium-Descemet complex.

CASE PRESENTATION

In November 2010 we performed EK without Descemet Stripping in a 3-month female newborn, thinking that the lower manipulation obtained by leaving the recipient endothelium-Descemet complex could be the key factor for the success of our surgery. Such a particular technique was new in newborns. The surgery was a success, but the long-term visual result was not predictable at that time. We followed the patient at 4 months, and then yearly. At the latest visit in October 2022 the visual, cognitive, and motorial developments were normal, with Best-corrected Distance Visual Acuity of 0.4 LogMAR with - 0.75 D sf + 2.75 D cyl @ 105° in the right eye (RE) and 0.4 LogMAR with + 1.50 D sf + 2.50 D cyl @ 60° in the left eye (LE). The endothelial microscope showed an unexpected healthy endothelium, with a cell count of 2383 cells/mm2 in the RE and of 2547 cells/mm2 in the LE from a starting donor count of 2900 cells/mm2. No secondary procedures were performed during the 12-year follow-up.

CONCLUSION

EK without Descemet stripping has proved to be a successful procedure over time in our newborn. The unexpected healthy endothelium suggests a role of the Descemet membrane in CHED.

Long-Term Outcomes of Descemet Membrane Endothelial Keratoplasty: Effect of Surgical Indication and Disease Severity

PURPOSE

The aim of this study was to evaluate clinical outcomes and graft survival in a large patient cohort up to 10 years after Descemet membrane endothelial keratoplasty (DMEK) based on surgical indication and Fuchs endothelial corneal dystrophy (FECD) severity.

METHODS

The cohort in this retrospective study included 750 eyes that underwent DMEK for FECD (86%), bullous keratopathy (BK, 9%), and other indications (5%). Based on the modified Krachmer grading, 186 eyes (29%) had moderate FECD (Krachmer grade 3-4) and 440 eyes (68%) had advanced FECD (Krachmer grade 5-6). Main outcome measures were best-corrected visual acuity (BCVA), central corneal thickness, endothelial cell density (ECD), endothelial cell loss (ECL), postoperative complication rate, and graft survival.

RESULTS

The mean 10-year BCVA was 0.08 ± 0.28 logMAR (n = 96), and the BCVA remained stable between 5 and 10 years postoperatively (all P > 0.05). The mean ECL at 5 and 10 years was 56% ± 17% (n = 460) and 66% ± 14% (n = 96), respectively ( P < 0.05). The 10-year graft survival rate for the total cohort was 0.85 (95% confidence interval, 0.82-0.89). BCVA and ECD differed at 1 to 5 years between eyes with different surgical indications (all P < 0.05), and FECD eyes had higher graft survival compared with BK eyes (0.90 vs. 0.60, P = 0.001). Moderate FECD eyes had better BCVA, ECD, and graft survival outcomes than advanced FECD eyes (all P < 0.05). Minor graft detachment ( P = 0.04) and lower donor ECD ( P = 0.01) were related to lower 10-year ECD.

CONCLUSIONS

Long-term outcomes and graft survival after DMEK were better in FECD eyes than BK eyes and were also related to FECD disease severity. Eyes operated for moderate FECD showed the highest graft survival probability and excellent long-term outcomes.

Non-invasive endothelial cell density measurement of in toto pre-stripped DMEK-roll - impact of pre- and intraoperative endothelial cell loss on postoperative midterm clinical outcome

BACKGROUND/OBJECTIVES

To measure the endothelial cell density (ECD) of the in toto pre-stripped endothelial Descemet membrane lamellae (EDML) and to describe the impact of pre- and intraoperative endothelial cell loss (ECL) on postoperative midterm clinical outcome.

SUBJECTS/METHODS

The ECD of 56 Corneoscleral Donor Discs (CDD) was first measured with an inverted specular microscope (t0pre). The measurement was then repeated non-invasively after the preparation of the EDML (t0post). DMEK was performed the next day using these grafts. Follow-up examinations took place 6 weeks, 6 months and 1 year postoperatively where the ECD was assessed. In addition, the impact of ECL 1 (during preparation) and ECL 2 (during surgery) on the ECD, visual acuity (VA) and pachymetry at 6 months and 1 year was investigated.

RESULTS

The average ECD (in cells/mm²) at time points t0pre, t0post, 6 weeks, 6 months & 1 year was 2584 ± 200, 2355 ± 207, 1366 ± 345, 1091 ± 564 and 939 ± 352. The average logMAR VA and pachymetry (in µm) was 0.50 ± 0.27 and 597 ± 63, 0.23 ± 0.17 and 535 ± 54, 0.16 ± 0.12 and 535 ± 54, 0.06 ± 0.08 and 512 ± 37, respectively The ECL 1 (9% on average) had no significant impact on the main outcome measures after 6 months and 1 year (p > 0.11). The ECL 2 correlated significantly with the ECD and the pachymetry at 1 year postop (p < 0.02).

CONCLUSION

Our results indicate that the non-invasive ECD measurement of the prestripped EDML roll before its transplantation is feasible. Despite significantly decreasing ECD up to 6 months postoperatively, visual acuity further improved and thickness further decreased up to 1 year postoperatively.

Ultrathin Descemet Stripping Automated Endothelial Keratoplasty (UT-DSAEK) versus Descemet Membrane Endothelial Keratoplasty (DMEK)-a systematic review and meta-analysis

BACKGROUND/OBJECTIVES

Endothelial keratoplasty (EK) is a commonly performed transplant procedure used in the treatment of corneal endothelial dysfunction. The aim of this systematic review and meta-analysis is to evaluate the differences in visual acuity outcomes, endothelial cell density (ECD) and complications between two forms of EK, ultrathin Descemet stripping automated endothelial keratoplasty (UT-DSAEK) and Descemet membrane endothelial keratoplasty (DMEK).

METHODS

A literature search of MEDLINE, Embase and Cochrane Library was conducted to identify studies reporting comparative results of UT-DSAEK versus DMEK. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was used for search strategy. Of 141 titles, 7 studies met the inclusion criteria; best corrected visual acuity (BCVA) (LogMAR), ECD (cells/mm2), and complications were compared, with all statistical analysis performed using Review Manager.

RESULTS

A total of 362 eyes were included for analysis. DMEK resulted in significantly better BCVA at 3 months (0.14 vs 0.22, p = 0.003), 6 months (0.08 vs 0.18, p = 0.005) and 1 year post-op (0.07 vs 0.14, p = 0.0005). UT-DSAEK resulted in significantly lower total complications (25.2% vs 57.3%, p = 0.0001) and rates of re-bubbling (11.0% vs 33.7%, p = 0.004). No differences were found in ECD between the two procedures (1541 vs 1605, p = 0.77).

CONCLUSIONS

DMEK results in superior visual acuity rates with quicker recovery. However, UT-DSAEK has a more favourable complication profile, particularly regarding lower rates of re-bubbling. Both are valuable options in the treatment of corneal endothelial disease and choice of procedure may depend on surgical expertise.

Cost Drivers of Endothelial Keratoplasty: A Time-Driven Activity-Based Costing Analysis

PURPOSE

To determine cost drivers of endothelial keratoplasty (EK) through evaluation of surgical costs and procedure length based on type of EK, use of preloaded grafts, and performance of simultaneous cataract surgery.

DESIGN

This study was an economic analysis of EKs at a single academic institution using time-driven activity-based costing (TDABC) methodology.

PARTICIPANTS

Endothelial keratoplasty surgical cases, including Descemet membrane endothelial keratoplasty (DMEK) and Descemet stripping automated endothelial keratoplasty (DSAEK), at the University of Michigan Kellogg Eye Center from 2016 to 2018 were included in the analysis.

METHODS

Data and inputs were obtained via the electronic health record (EHR) and from prior literature. Simultaneous cataract surgeries were included and separately categorized for analysis. Endothelial keratoplasty expenses were determined with TDABC, a method for cost calculation that incorporates the time that key resources are used and each resource's associated cost rate.

MAIN OUTCOME MEASURES

Main outcome measures included surgery length (in minutes) and day-of-surgery costs.

RESULTS

There were 559 EKs included: 355 DMEKs and 204 DSAEKs. Fewer DSAEKs had simultaneous cataract extraction (47; 23%) than DMEK (169; 48%). Of the DMEKs, 196 (55%) used preloaded corneal grafts. Descemet membrane endothelial keratoplasty cost $392.31 less (95% confidence interval, $251.05-$533.57; P < 0.0001) than DSAEK and required 16.94 fewer minutes (14.16-19.73; P < 0.0001). Descemet membrane endothelial keratoplasty cases that used preloaded corneal grafts cost $460.19 less ($316.23-$604.14; P < 0.0001) and were 14.16 minutes shorter (11.39-16.93; P < 0.0001). In multivariate regression, preloaded graft use saved $457.19, DMEK (compared with DSAEK) saved $349.97, and simultaneous cataract surgery added $855.17 in day-of-surgery costs.

CONCLUSIONS

Cost analysis of TDABC identified a day-of-surgery cost and surgical time reduction associated with the use of preloaded grafts for DMEK, DMEK compared with DSAEK, and isolated EK compared with EK combined with cataract surgery. This study provides an improved understanding of surgical cost drivers and margin incentivization, which may explain trends and indirectly influence patient care decisions in cornea surgery practices.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Comparison of penetrating and endothelial keratoplasty in patients with iridocorneal endothelial syndrome: A registry study

BACKGROUND

To compare graft survival of endothelial keratoplasty (EK) versus penetrating keratoplasty (PK) in patients with iridocorneal endothelial (ICE) syndrome and identify ocular features associated with graft survival.

METHODS

Observational, prospective, cohort study. A total of 30 806 first grafts performed between 1985 and 2020 were identified through the Australian Corneal Graft Registry and included in this observational, prospective cohort study. A total of 196 eyes underwent a primary corneal graft for ICE syndrome. Kaplan-Meier graft survival plots and Chi-squared tests were performed to identify graft survival rates for EK and PK. A history of raised intraocular pressure (IOP) was also recorded and analysed. Graft survival of eyes with ICE syndrome were compared to that of other indications.

RESULTS

Grafts performed for ICE syndrome increased to 0.8% of all cases during the 2005 to 2020 period compared with 0.5% between 1985 to 2004 (χ2 =9.35, p = 0.002). From 2010, EK surpassed PK as the preferred graft type. Survival of primary grafts in eyes with ICE syndrome was lower than for other indications (log-rank = 56.62, p < 0.001). Graft survival was higher following PK than Descemet stripping (automated) endothelial keratoplasty (DS(A)EK) (log-rank = 10.56, p = 0.001). Graft survival was higher in eyes without a history of raised IOP compared to those with a reported history of raised IOP (log-rank = 13.06, p < 0.001).

CONCLUSIONS

ICE syndrome carries a poor prognosis for graft survival. DS(A)EK had a poorer prognosis than PK. A history of raised IOP is associated with higher risk of graft failure.

Refractive outcomes after DMEK: meta-analysis

In this meta-analysis and systematic literature review of refractive outcomes after Descemet membrane endothelial keratoplasty (DMEK), the extent of the refractive shift and an overview of reasons for refractive shift after DMEK are provided. The PubMed library was screened for articles containing the terms "Descemet membrane endothelial keratoplasty," "DMEK," "Descemet membrane endothelial keratoplasty combined with cataract surgery," "triple-DMEK" combined with "refractive outcomes," "refractive shift," and "hyperopic shift." The refractive outcomes after DMEK were analyzed and compared using a fixed and random effects model. The overall mean change of the spherical equivalent outcome when compared with the preoperative value in cases of DMEK or when compared with the preoperative target refraction in cases of DMEK combined with cataract surgery was +0.43 diopters (D) (95% CI, 0.31-0.55). When DMEK is combined with cataract surgery, a target refraction of -0.5 D is recommended to achieve emmetropia. Changes in the posterior corneal curvature are identified as the main cause of the refractive hyperopic shift.

Descemet membrane endothelial keratoplasty graft detachments in superior versus temporal approach

PURPOSE

To evaluate the difference in Descemet Membrane Endothelial Keratoplasty (DMEK) graft detachment rate comparing superior versus temporal main incision approach.

METHODS

Retrospective comparative study on patients who underwent DMEK surgery for Fuchs endothelial dystrophy or bullous keratopathy with main wound incision performed at either 90° in the superior approach, or at 180°/0° in the temporal approach. All main incisions were secured with a single 10-0 nylon suture at the end of surgery. Data collected were donor age and gender, endothelial cell counts, graft diameter, recipient age and gender, indication for transplant, surgeon grade, re-bubbling rate, air fill in the anterior chamber (AC) at day one and intra- and early postoperative complications.

RESULTS

187 eyes were included in the study. 99 eyes had DMEK surgery with superior approach, while 88 eyes had temporal approach. The two groups had no differences in donor age and sex, endothelial cell counts, graft diameter, recipient age and sex, indication for transplant, surgeon grade, and air fill in the anterior chamber at day one. Re-bubbling rate was 38.4% for surgeries performed with superior access and 29.5% for those with temporal access(p = 0.186). After exclusion of patients with intraoperative and/or postoperative complication, the difference in re-bubbling rate was higher, although non-significant (37.5% and 25% for superior and temporal approach respectively, p = 0.098).

CONCLUSION

The temporal approach in DMEK showed a trend towards a clinically significant lower rate of post-operative re-bubbling compared to the superior approach, however, no statistically significant difference was noted comparing the two approaches, which both remain feasible options in DMEK surgery.

Phacoemulsification, pinhole pupilloplasty, and pre-Descemet's endothelial keratoplasty for keratoconus with Fuchs' endothelial dystrophy

The comorbidity of keratoconus with Fuchs' endothelial dystrophy with cataract is a rare clinical combination. We present an amalgamation of surgical techniques to manage the above clinical conditions and its complications in single setting. The modified triple procedure, namely, the phacoemulsification, pinhole pupilloplasty, and pre-Descemet's endothelial keratoplasty (PDEK) in the order of description is followed in single sitting. Lens removal by phacoemulsification, correction of irregular astigmatism by pinhole pupilloplasty (pinhole optics), and exchanging the endothelial layer for PDEK forms the main segments of the triple procedure. This combination of techniques may decrease the risk of multiple surgeries and its related complications. Moreover, it will allow the patient for faster visual rehabilitation by improving the uncorrected visual acuity and visual quality.

Video Grading of Descemet Membrane Endothelial Keratoplasty Surgery to Identify Surgeon Risk Factors for Graft Detachment and Rebubbling: A Post Hoc Observational Analysis of the Advanced Visualization In Corneal Surgery Evaluation Trial

PURPOSE

The aim of this study was to explore video-graded intraoperative risk factors for graft detachment (GD) and rebubbling in Descemet membrane endothelial keratoplasty surgery.

METHODS

A post hoc analysis of 65 eyes of 65 pseudophakic subjects with Fuchs endothelial dystrophy that underwent Descemet membrane endothelial keratoplasty surgery as part of the Advanced Visualization In Corneal Surgery Evaluation trial. All surgical recordings were assessed by 2 graders using a structured assessment form. A multinominal regression was performed to estimate the independent effect of video-graded intraoperative factors on the incidence of GD and rebubbling. Secondary outcomes are corrected distance visual acuity and endothelial cell density.

RESULTS

In total, 33 GDs were recorded, of which 17 required rebubbling. No significant predictors for GD or rebubbling were identified. However, the results revealed 2 clinically relevant patterns. An unfavorable graft configuration (ie, wrinkled, tight scroll, or taco-shaped) and a gas-bubble size smaller than the graft diameter were associated with an increased risk of GD [odds ratio (OR) 2.5 and OR 2.26, respectively] and rebubbling (OR 2.0 and OR 2.60, respectively). Inversely, a larger gas-bubble size was associated with a reduced risk of GD (OR 0.37) and rebubbling (OR 0.36). At 3 and 6 months postoperatively, corrected distance visual acuity was poorer in subjects requiring a rebubbling and endothelial cell density loss was higher in subjects with a partial GD.

CONCLUSIONS

Our analysis revealed that the gas-bubble size and graft shape/geometry seem to be relevant clinical factors for GD and rebubbling, whereas descemetorhexis difficulty, degree of graft manipulation, graft overlap, and surgical iridectomy were not associated with an increased risk.

Descemet Stripping Without Endothelial Keratoplasty in Early-Stage Central Fuchs Endothelial Dystrophy: Long-term Results

PURPOSE

The purpose of this study was to report long-term results of Descemet stripping without endothelial keratoplasty (DWEK) associated with phacoemulsification in patients with early-stage central Fuchs endothelial corneal dystrophy.

METHODS

This is a retrospective study, including all patients submitted to DWEK associated with cataract surgery with a minimum follow-up of 24 months. Included patients had central confluent guttae confirmed with specular microscopy, a clear peripheral endothelium (with a peripheral endothelial count >1500 cells/mm 2 ), and a central pachymetry <600 μm. The main end points were the presence of a clear cornea and time that was needed to achieve transparency, best-corrected visual acuity in logMAR, endothelial central cell count (ECC), and central pachymetry.

RESULTS

A total of 22 eyes were included with a mean follow-up of 40.8 ± 10.5 months. At baseline, mean central pachymetry was 536 ± 34 mm and 6 eyes had countable ECC (mean 1138 ± 190 cells/mm 2 ). Twenty eyes (90.9%) achieved good corneal transparency 3.2 ± 1.1 months after surgery. There was a significant improvement in logMAR best-corrected visual acuity compared with baseline (0.13 ± 0.10 vs. 0.48 ± 0.24, respectively, P < 0.001). Endothelial central repopulation was observed in all successful cases. Twelve months after DWEK, ECC was 1449 ± 344 cells/mm 2 and 1393 ± 450 cells/mm 2 at the end of follow-up, without a significant decrease between this period ( P = 0.081). Only 2 eyes (9.1%) did not achieve corneal transparency and were submitted to an endothelial keratoplasty.

CONCLUSIONS

According to our results, DWEK is a safe and effective procedure in selected cases of early-stage central Fuchs endothelial corneal dystrophy. This seems to be a promising technique, delaying or avoiding endothelial transplantation.

Impact of topographic hot spots on the refractive outcomes of combined DMEK and cataract surgery

PURPOSE

To compare the refractive results of combined Descemet membrane endothelial keratoplasty (DMEK) and cataract surgery in eyes with Fuchs endothelial corneal dystrophy (FECD) with and without topographic hot spots.

SETTING

"Villa Igea" Hospital, Forlì, Italy.

DESIGN

Interventional case series.

METHODS

57 eyes of 52 patients with FECD undergoing combined DMEK, cataract surgery, and monofocal intraocular lens (IOL) implantation were included in this single-center study. Patients were classified based on the presence or absence of topographic hot spots on the preoperative axial power map. Prediction error (PE) was calculated as the postoperative manifest spherical equivalent (SE) refraction minus the SE predicted refraction.

RESULTS

6 months postoperatively, mean PE was +0.79 ± 1.12 diopters (D). In eyes with hot spots, mean keratometry (K), K flat, and K steep significantly decreased after surgery (all P < .05), whereas no significant changes were observed in eyes without hot spots (all P > .05). Eyes with hot spots showed a significantly more hyperopic PE than eyes without hot spots (+1.13 ± 1.23 vs +0.40 ± 0.86 D; P = .013).

CONCLUSIONS

Combined DMEK and cataract surgery can result in a hyperopic refractive surprise. The presence of topographic hot spots before surgery is associated with a higher hyperopic shift.

Rebubbling and graft detachment in Descemet membrane endothelial keratoplasty using a standardised protocol

OBJECTIVES

To analyse risk factors and long-term outcomes after rebubbling and graft detachment in Descemet membrane endothelial keratoplasty (DMEK).

METHODS

176 consecutive DMEK grafts of 125 patients performed by 8 surgeons with a standardised technique between January 2015 and July 2022 were analysed. Main outcome measures were graft detachments, rebubbling rate, postoperative outcomes, and risk factors for graft failure and rebubbling.

RESULTS

6 (3.4%) grafts required rebubbling (>1/3 area detached). 40 (22.7%) grafts developed self-resolving partial detachments (<1/3 area detached). The mean time to rebubble was 16 ± 9.4 days. Mean BSCVAs at 5 years postoperative were 0.03 ± 0.16, 0.03 ± 0.14, and 0.15 ± 0.31 logMAR in fully attached, partially detached and rebubbled grafts (P = 0.437). 5-year graft survival were 98%, 90%, and 83% in fully attached, partially detached and rebubbled eyes (P = 0.02). There was significantly greater endothelial cell loss (ECL) in the rebubbled eyes (P = 0.018). Intraoperative trauma was a risk factor for graft failure (HR 1.81; 95% CI: 1.33-2.50; P = 0.023). An indication for surgery other than Fuchs endothelial dystrophy was a risk factor for rebubbling (HR 5.28; 95% CI: 5.11-72.4; P = 0.007).

CONCLUSION

DMEK grafts had better graft survival if there was no partial detachment or rebubbling at 5 years postop. There was significant ECL associated with rebubbling. A standardised technique reduces rebubbling and graft failure risk.