To compare results of the first 100 eyes of Descemet stripping automated endothelial keratoplasty (DSAEK) and Descemet membrane endothelial keratoplasty (DMEK) that were performed with a standardized ...technique at a single institution.
Single-center, retrospective case series.
The first 100 eyes of standardized DSAEK and DMEK that underwent surgery for Fuchs corneal dystrophy at our center. We excluded patients with prior ocular surgery other than cataract surgery to limit confounding variables.
Best spectacle-corrected visual acuity (BSCVA; in logarithm of the minimal angle of resolution logMAR units) was obtained and specular microscopy of donor corneal tissue was performed before surgery. Postoperative complications, BSCVA, and the percent of endothelial cell loss (ECL) recorded at 6 months were compared with the Student t test. Patients with pre-existing ocular comorbidity that impacted visual potential such as macular degeneration, amblyopia, advanced glaucoma, and other optic neuropathies were excluded from the analysis of visual acuity, but were included for the outcomes of complications and ECL.
Visual acuity improvement, ECL 6 months after surgery, postoperative complications, iatrogenic primary graft failure (IPGF), and rebubbling.
Of the 200 eyes, 62 DSAEK eyes and 70 DMEK eyes had 6-month BSCVA available and no vision-limiting comorbidities. Mean BSCVA increased from 0.41±0.19 logMAR and 0.27±0.11 logMAR before surgery to 0.20±0.13 logMAR and 0.11±0.13 logMAR 6 months after DSAEK and DMEK, respectively (P<0.001). Seventy-one DSAEK eyes and 70 DMEK eyes had 6-month ECL data available: ECL was 25.9±14.0% after DSAEK and 27.9±16.0% after DMEK (P=0.38). There were no IPGFs in the DSAEK cohort and there were 4 of 100 IPGFs after DMEK (P=0.12). Rebubbling was performed in 2 of 100 eyes after DSAEK and in 6 of 100 eyes after DMEK (P=0.28).
Compared with DSAEK, DMEK provided better visual recovery and comparable 6-month ECL. The DMEK group had a higher, although not statistically significant, percentage of rebubbling procedures and IPGFs.
To evaluate the long-term improvement of visual acuity after Descemet's stripping automated endothelial keratoplasty (DSAEK) surgery.
Retrospective analysis of a noncomparative, interventional case ...series.
One hundred eight patients undergoing DSAEK surgery for Fuchs' endothelial dystrophy and pseudophakic bullous keratopathy without other ocular comorbidities who completed a full 3-year follow-up period.
Postoperative best spectacle-corrected visual acuity (BSCVA) was recorded at 6, 12, 24, and 36 months. Improvement in BSCVA between each time point was evaluated using paired-samples t tests. Subanalysis evaluating the percentage of eyes achieving a BSCVA of 20/20, 20/25, 20/30, and 20/40 at each time point was performed.
Improvement in postoperative BSCVA.
There was a statistically significant trend toward improvement in average BSCVA with time at postoperative month 6 and postoperative years 2 and 3. There were also increasing proportions of eyes reaching vision of 20/20, 20/25, and 20/30 from 6 months to 1 year, 1 year to 2 years, and 2 years to 3 years. The percentage of patients achieving 20/25 BSCVA improved from 36.1% at 6 months to 70.4% at 3 years after surgery. A similar increase in the percentage of patients reaching a BSCVA of 20/20 after DSAEK surgery also was observed from 11.1% at 6 months to approximately 47.2% at 3 years.
There is gradual improvement of visual acuity over time after DSAEK surgery for Fuchs' endothelial dystrophy and pseudophakic bullous keratopathy in patients without other vision-limiting ocular comorbidities.
Proprietary or commercial disclosure may be found after the references.
To report low complication rates in Descemet membrane endothelial keratoplasty (DMEK) using sulfur hexafluoride (SF6) gas, a novel glass injector, and donor tissue prestripped by an eye bank ...technician.
A standardized technique of DMEK was performed in 80 consecutive Fuchs corneal dystrophy cases using technician-prestripped tissue, a novel glass injector, a modified Yoeruek tap technique, and an SF6 gas (20% concentration) bubble for prolonged tissue support. Twenty-five donors were premarked with an "S" stamp for intraoperative orientation. Surgery was performed by 2 experienced DMEK surgeons and 2 inexperienced cornea fellows. Complications were recorded, and the percent endothelial cell loss was calculated at 6 months postoperatively.
There were 5 cases that received an air bubble injection postoperatively (6% rebubble rate). There were 6 grafts that immediately failed, 2 because of excessive surgical trauma, and 4 because of upside-down graft placement documented by optical coherence tomography. None of the 25 cases with an S stamp failed. Recipient corneas cleared quickly with no clinical evidence of toxicity from the SF6 gas bubble, and the grafts experienced a mean endothelial cell loss of 27% at 6 months.
Tissue prestripped by an eye bank technician can be safely used for DMEK surgery. SF6 gas for prolonged tissue support may reduce the rebubble rate in DMEK, with no apparent acute toxic effect. An unrecognized upside-down graft was the primary cause of graft failure in this series. Upside-down grafts may be eliminated by the use of donor tissue premarked by the eye bank with an S orientation stamp.
To present 6-month clinical outcomes from a series of 165 consecutive Descemet membrane endothelial keratoplasty (DMEK) procedures before and after the introduction of a novel stromal-sided S-stamp ...preparation technique that has decreased the incidence of iatrogenic primary graft failure by eliminating upside-down grafts.
Retrospective nonrandomized comparative case series.
We included 165 consecutive eyes that had undergone DMEK surgery for Fuchs' or pseudophakic bullous keratopathy. These cases were divided into 2 cohorts: the first cohort comprised 31 cases that used unstamped tissue before the S-stamp was introduced, and the second cohort comprised 133 cases after the S-stamp was incorporated into the standardized technique. A single unstamped DMEK case was performed after the introduction of the S-stamp for a total of 32 unstamped cases.
Donor materials were prepared at a single eye bank using a standardized technique, which subsequently incorporated the addition of a dry ink gentian violet S-stamp to the stromal side of Descemet membrane. All surgeries were performed at a single clinical site by 5 surgeons (2 attending surgeons and 3 fellows). Two of the 165 DMEK cases were performed for pseudophakic bullous keratopathy (2 cases, 1 in each cohort), and the remaining cases were for Fuchs' endothelial dystrophy. Primary outcome measures were assessed at 6 months and maintained in a prospective institutional review board-approved study.
We analyzed the 6-month endothelial cell density, incidence of iatrogenic primary graft failure, upside-down graft implantation, and rebubble events.
The S-stamp eliminated upside-down graft implantations (0/133 S-stamped vs 3/32 unstamped) and did not significantly alter 6-month endothelial cell loss (31±17% S-stamped vs 29±14% unstamped; P = 0.62) or frequency of rebubble (17/133 S-stamped vs 1/32 unstamped; P = 0.20).
The incorporation of a stromal-sided S-stamp eliminates iatrogenic primary graft failure owing to upside-down implantation of DMEK grafts, without adversely affecting early postoperative complications or 6-month endothelial cell loss.
To determine whether preoperative donor thickness has a relationship with postoperative visual acuity after Descemet's stripping automated endothelial keratoplasty (DSAEK).
Retrospective correlation ...and comparative analysis of an interventional case series.
A total of 418 eyes of 292 patients undergoing DSAEK surgery for Fuchs' endothelial dystrophy without visual loss from comorbidities.
Descemet's stripping automated endothelial keratoplasty was performed in 548 eyes with Fuchs' dystrophy, and preoperative graft thickness (GT) was recorded. After exclusion of patients with confounding variables that would affect postoperative visual acuity, postoperative best spectacle-corrected visual acuity (BSCVA) was measured at 6 months in 418 eyes. Pearson's correlation analysis was performed between preoperative GT and BSCVA. Cases were split into deciles on the basis of GT and BSCVA and then compared with 1-way analysis of variance (ANOVA) and chi-square test.
Best spectacle-corrected visual acuity at 6 months postoperatively.
Mean GT of the series was 162.9±29.0 μm (range, 80-265 μm), and mean Snellen BSCVA was 20/28 with a range of 20/16 to 20/70. There was a weak correlation between GT and BSCVA that was significant (R = 0.236, P<0.001) but only accounted for 5% of the visual outcome (R(2) = 0.056). Visual outcome was best within the thinnest decile group of 45 donors (GT range, 80-124), with a mean Snellen BSCVA of 20/25 (range, 20/20-20/50), and worst within the thickest decile group of 41 donors (GT range, 200-265), with a mean Snellen BSCVA of 20/33 (range, 20/20-20/70). Post hoc comparison of BSCVA between the thickest and thinnest groups was significant (P = 0.006).
Preoperative GT may have a small effect on visual outcome in the extremes of thickness, but not in the common range of 100 to 200 μm. Donor thickness has a tenuous relationship with visual outcome, accounting for only 5% of the variance in vision between patients, and should play a minimal role in surgical planning.
To examine the long-term effect of donor diabetes history on graft failure and endothelial cell density (ECD) after penetrating keratoplasty (PK) in the Cornea Donor Study.
Multicenter, prospective, ...double-masked, controlled clinical trial.
One thousand ninety subjects undergoing PK for a moderate risk condition, principally Fuchs' dystrophy or pseudophakic or aphakic corneal edema, were enrolled by 105 surgeons from 80 clinical sites in the United States.
Corneas from donors 12 to 75 years of age were assigned by 43 eye banks to participants without respect to recipient factors. Donor and recipient diabetes status was determined from existing medical records. Images of the central endothelium were obtained before surgery (baseline) and at intervals for 10 years after surgery and were analyzed by a central image analysis reading center to determine ECD.
Time to graft failure (regraft or cloudy cornea for 3 consecutive months) and ECD.
There was no statistically significant association of donor diabetes history with 10-year graft failure, baseline ECD, 10-year ECD, or ECD values longitudinally over time in unadjusted analyses, nor after adjusting for donor age and other significant covariates. The 10-year graft failure rate was 23% in the 199 patients receiving a cornea from a donor with diabetes versus 26% in the 891 patients receiving a cornea from a donor without diabetes (95% confidence interval for the difference, -10% to 6%; unadjusted P=0.60). Baseline ECD (P=0.71), 10-year ECD (P>0.99), and changes in ECD over 10 years (P=0.86) were similar comparing donor groups with and without diabetes.
The study results do not suggest an association between donor diabetes and PK outcome. However, the assessment of donor diabetes was imprecise and based on historical data only. The increasing frequency of diabetes in the aging population in the United States affects the donor pool. Thus, the impact of donor diabetes on long-term endothelial health after PK or endothelial keratoplasty, or both, warrants further study with more precise measures of diabetes and its complications.
To determine the concentration of amphotericin B that would be both effective against Candida albicans contamination and safe for corneal endothelial cells (CECs) in cold storage conditions.
...Triplicate media cultures were inoculated with 10 colony-forming units (CFUs)/mL of C. albicans (American Type Culture Collection 10231), supplemented with amphotericin B (0-20 μg/mL), stored in cold conditions (2°C-8°C) for 72 hours, and analyzed quantitatively for CFUs. C. albicans concentration in each sample was determined initially and after 6, 24, 48, and 72 hours of storage. CEC mitochondrial function (oxygen consumption rate), apoptosis, and necrosis were examined in donor corneas after 7 days of amphotericin B exposure and compared with untreated controls. CEC viability was also examined by calcein-AM staining and Fiji segmentation after 72 hours or 2 weeks of amphotericin B exposure to mimic potential eye bank practices.
Amphotericin B concentrations of 1.25, 2.5, and 5.0 μg/mL resulted in 0.47, 1.11, and 1.21 log10 CFU reduction after only 6 hours of cold storage and continued to decrease to 3.50, 3.86, and 4.49 log10 reductions after 72 hours, respectively. By contrast, amphotericin B 0.255 µg/mL showed only 1.01 log10 CFU reduction after 72 hours of incubation. CEC mitochondrial function and viability did not differ in donor corneas exposed to amphotericin B ≤2.59 μg/mL compared with the controls.
Optimal efficacy of amphotericin B against C. albicans is achieved in cold storage conditions at concentrations ≥1.25 μg/mL, and 2.5 μg/mL reduces Candida contamination by >90% after 6 hours of cold storage without sacrificing CEC health.
To report the donor endothelial cell loss in the first year after Descemet's stripping endothelial keratoplasty (DSEK) for the treatment of endothelial dysfunction.
Prospective noncomparative ...interventional case series.
Eighty eyes of 78 patients with corneal edema.
Eighty eyes with endothelial failure were entered into a prospective study of endothelial keratoplasty (EK). The donor central endothelial cell density (ECD) was recorded postoperatively at 6 months (n = 80) and 12 months (n = 80) and then compared with the preoperative eye bank measurements. The subsets of eyes with the donor prepared manually (DSEK; n = 19) and the donor prepared with a microkeratome (Descemet's stripping automated EK DSAEK; n = 61) were also evaluated and compared.
Preoperative and postoperative central ECDs were prospectively evaluated and the cell loss calculated for each postoperative time point.
The average and standard deviation ECD at 6 months was 1908+/-354 cells/mm(2), representing a mean cell loss from preoperative donor cell measurements of 34+/-12%. At 12 months, ECD was 1856+/-371 cells/mm(2) (35+/-13% cell loss). The 1% additional cell loss from 6 to 12 months was not significant (P = 0.233). In the subset of DSEK eyes (n = 19), the cell loss from preoperatively to 6 months was 34%, and at 12 months it was 39%. In the subset of DSAEK eyes (n = 61), the cell loss from preoperatively to 6 months was 34%, and at 12 months it was 34%. There was no statistical difference between the cell loss from DSEK and that from DSAEK at 6 months (P = 0.884) or at 12 months (P = 0.224).
Descemet's stripping EK using our surgical technique has a mean donor endothelial cell loss of 34% at the 6-month postoperative examination, and this average cell loss remains relatively stable up to at least 1 year. We found no difference in cell loss between the DSEK and DSAEK techniques over this 1-year postoperative period.
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