For Fuchs Endothelial Corneal Dystrophy Research Articles

Cataract surgery with corneal endothelial pathology

Abstract: It is not uncommon for Fuch’s endothelial corneal dystrophy (FECD) patients to present with a co-existent cataract. Surgeons are often faced with a choice between simultaneous and staged corneal and cataract surgery. Descemet’s membrane endothelial keratoplasty (DMEK) has been found to have better visual outcomes as compared to Descemet’s stripping endothelial keratoplasty (DSEK) and penetrating keratoplasty and is currently the preferred surgery for FECD. Endothelial cell count and pachymetry cutoffs were earlier used for decision-making. Various other investigations such as Scheimpflug imaging and confocal microscopy are now used to prognosticate the outcome when performing cataract surgery only. Triple DMEK has the advantage of a definite treatment in a single sitting. Whereas, a staged approach with DMEK followed by cataract surgery has a better visual outcome. This is due to variable refractive changes in the cornea post-DMEK or DSEK that can lead to inaccurate intraocular lens (IOL) power calculation. Even though the graft detachment rates and rebubbling rates have been found to be comparable in triple DMEK versus a staged surgery, in view of increasing patient demands and expectations for a spectacle-independent outcome, a staged surgery is now preferable. Conventionally, surgeons favored the use of only monofocal lenses; however, the use of premium IOLs, especially extended depth of focus lenses, is now increasing. In this review, we will discuss the various advantages and disadvantages of a simultaneous and staged approach and pearls on decision-making in FECD with cataracts.

Descemet Stripping Only: Long-Term Outcomes.

Descemet stripping only (DSO) is a relatively novel treatment for Fuchs endothelial corneal dystrophy (FECD). In this procedure, a central area of Descemet membrane and endothelium is removed without the insertion of donor tissue. Evaluation of long-term outcomes (≥5 years) after DSO is imperative to establish the validity of this procedure and to determine its role in the management of Fuchs endothelial dystrophy. Published outcomes are limited but promising. This study evaluates the 5- and 6-year outcomes of patients who had DSO at a single institution. This is a retrospective chart review of patients with FECD who underwent DSO in 2016 and 2017. Eleven patients and 13 eyes met the criteria. Twelve of 13 eyes achieved corneal clearance. Two eyes had corneal decompensation requiring subsequent endothelial keratoplasty (EK). Of the 10 eyes that maintained clear corneas, 9 had a best-corrected visual acuity (BCVA) of at least 20/30 (mean logarithm of the minimim angle of resolution [logMAR] visual acuity [VA] 0.18 ± 0.16) at 5 years post-operatively (POY5). At 6 years, 7 of 8 eyes had a VA better than 20/40 (mean logMAR VA 0.17 ± 0.04). One patient had decreased VA due to progression of macular degeneration. Patients who required EK achieved good vision and corneal clearance. This is the largest series of patients with long-term follow-up after DSO. Ten of the 13 eyes (77%) responded and maintained clear central corneas for at least 5 years. Patients with failed DSO can achieve corneal clearance and good vision with subsequent EK. These patient outcomes support the role of DSO in the management of patients with FECD.

Systematic Review of the Diagnostic Criteria and Severity Classification for Fuchs Endothelial Corneal Dystrophy.

There are no defined diagnostic criteria and severity classification for Fuchs endothelial corneal dystrophy (FECD), which are required for objective standardized assessments. Therefore, we performed a systematic literature review of the current diagnosis and severity classification of FECD. We searched the Ovid MEDLINE and Web of Science databases for studies published until January 13, 2021. We excluded review articles, conference abstracts, editorials, case reports with <5 patients, and letters. Among 468 articles identified, we excluded 173 and 165 articles in the first and second screenings, respectively. Among the 130 included articles, 61 (47%) and 99 (76%) mentioned the diagnostic criteria for FECD and described its severity classification, respectively. Regarding diagnosis, slitlamp microscope alone was the most frequently used device in 31 (51%) of 61 articles. Regarding diagnostic findings, corneal guttae alone was the most common parameter [adopted in 23 articles (38%)]. Regarding severity classification, slitlamp microscopes were used in 88 articles (89%). The original or modified Krachmer grading scale was used in 77 articles (78%), followed by Adami's classification in six (6%). Specular microscopes or Scheimpflug tomography were used in four articles (4%) and anterior segment optical coherence tomography in one (1%). FECD is globally diagnosed by the corneal guttae using slitlamp examination, and its severity is predominantly determined by the original or modified Krachmer grading scale. Objective severity grading using Scheimpflug or anterior segment optical coherence tomography can be applied in the future innovative therapies such as cell injection therapy or novel small molecules.

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

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). 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. 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). 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.

Predicting Corneal Improvement after Descemet Membrane Endothelial Keratoplasty for Fuchs Endothelial CornealDystrophy.

PurposeTo develop a model to predict corneal improvement after Descemet membrane endothelial keratoplasty (DMEK) for Fuchs endothelial corneal dystrophy (FECD) from Scheimpflug tomography.DesignCross-sectional study.ParticipantsForty-eight eyes (derivation group) and 45 eyes (validation group) with a range of severity of FECD undergoing DMEK.MethodsScheimpflug images were obtained before and after DMEK. Before DMEK, pachymetry map and posterior elevation map patterns were quantified by a special image analysis program measuring tomographic features of edema (loss of regular isopachs, displacement of the thinnest point of the cornea, posterior surface depression). Image-derived novel parameters were combined with instrument-derived parameters, and the relative influences of parameters associated with the change in central corneal thickness (CCT) after DMEK in the derivation group were determined by using a gradient boosting machine learning model. The parameters with highest relative influence were then fit in a linear regression model. The derived model was applied to the validation group. Correlations and agreement were assessed between predicted and observed changes in CCT.Main Outcome MeasuresPredictive power (R2) and mean difference between predicted and observed change in CCT.ResultsThe gradient boosting machine model identified 4 novel parameters of isopach circularity and eccentricity and 1 instrument-derived parameter (posterior surface radius); preoperative CCT was a poor predictor. In the derivation group, the model strongly predicted the change in CCT after DMEK (R2 = 0.80; 95% confidence interval [CI], 0.71–0.89) and the mean difference between predicted and observed change was, by definition, 0 μm. When the same 5 parameters were fit to the validation group, the model performed very highly (R2 = 0.89; 95% CI, 0.84–0.94). When the coefficient estimates from the derivation model were used to predict the change in CCT in the validation group, the predictive power was also high (R2 = 0.78; 95% CI, 0.68–0.88), and the mean difference was 4 μm (predicted minus observed).ConclusionsScheimpflug tomography maps of corneas with FECD can predict the improvement in CCT after DMEK, independent of preoperative corneal thickness measurement. The model could be applied in clinical practice or for clinical research of FECD.

Graft survival and clinical outcomes of Descemet membrane endothelial keratoplasty: long-term results.

The aim is to report long-term graft survival rates and clinical outcomes of Descemet membrane endothelial keratoplasty (DMEK). In this study 150 eyes that underwent DMEK whether for Fuchs endothelial corneal dystrophy (FECD) or for bullous keratopathy (BK) surveilled for 7years at 6 time points to evaluate graft survival rates and clinical outcomes of post-corneal transplantation. Overall, the estimated survival probability of 95% confidence interval at 7years of post-DMEK was 0.58 (0.72-0.77), and the survival probabilities of eyes operated for FECD (0.53) were higher than eyes operated for BK (0.42) (log rank 26.87, [p = 0.197]). Post-transplant eyes with FECD achieved better visual acuity levels than eyes with BK (p = 0.006). Primary graft failure occurred in 11.3% eyes. Secondary graft failure rate was 9.3%, and allograft rejection rate was 4.7%. Although DMEK is effective and safe in long term, visual results and graft survival rates are better in cases with FECD.

New severity grading system for Fuchs endothelial corneal dystrophy using anterior segment optical coherence tomography.

To report a new severity grading system for Fuchs endothelial corneal dystrophy (FECD) using anterior segment optical coherence tomography (AS-OCT). This observational case series included 75 eyes of 43 patients with FECD and 33 eyes of 33 healthy subjects. Pachymetry and posterior elevation maps were used to determine the AS-OCT-based grading scores. FECD severity was graded from 0-3 as follows: 0, normal; 1, guttae only; 2, stromal oedema; and 3, epithelial and stromal oedema. We further investigated the central corneal thickness (CCT), thinnest corneal thickness (TCT), anterior and posterior best-fit spheres (BFS), and the distance between the central cornea and the thinnest point. Thirty-three eyes were graded as 0, four as 1, thirteen as 2, fourteen as 3, twenty-nine as 4, eleven as 5 and four as 6 by the modified Krachmer grade. Thirty-three, 41, 30 and 4 eyes were graded as 0, 1, 2 and 3, respectively, by the AS-OCT-based grading system. The inter-observer agreement was 100% for the AS-OCT-based grading system. The CCT, TCT, posterior BFS, and distance between the central cornea and thinnest point were significantly different between AS-OCT-based grades (p=0.0001, 0.0001, 0.0036 and 0.0001, respectively). Anterior BFS was not significantly different with the AS-OCT-based grades (p=0.1184). We devised a new severity grading using only objective evaluation and quantitatively demonstrated corneal thickening, predominant flattening of the posterior corneal surface compared with the anterior surface, and displacement of the thinnest point away from the central cornea with FECD progression.

Two-year clinical outcome after Descemet membrane endothelial keratoplasty using a standardized protocol.

Purpose:The purpose of this study is to evaluate 2-year clinical outcome after Descemet membrane endothelial keratoplasty (DMEK) in a variety of endothelial dysfunctions using a standardized protocol.Methods:From a group of 230 eyes which underwent DMEK for Fuchs' endothelial corneal dystrophy (FECD), aphakic and pseudophakic bullous keratopathy, failed full thickness corneal transplants, ICE syndrome, failed DSEK, and TASS the clinical outcomes [best spectacle-corrected visual acuity (BSCVA), central endothelial cell density (ECD)] were evaluated before, and at 6, 12, and 24 months and the success rate, failure rate and postoperative complications were also analyzed.Results:Out of 230 eyes, 144 eyes (70%) had BSCVA 6/9 or better 2 years postoperatively. Mean donor ECD was 2692.23 (range, 2300–3436) cells/mm2 preoperatively, which was reduced to 1433.64 (range, 619.0–2272.0) cells/mm2 2 years after DMEK surgery, indicating a mean reduction of 1258 cells/mm2 (46%) in ECD.Conclusion:DMEK is a highly successful surgical procedure when following a standard protocol for treating diseases of the corneal endothelium providing a near perfect anatomic restoration and a high degree of visual rehabilitation.

Parameters Associated With Endothelial Cell Density Variability After Descemet Membrane Endothelial Keratoplasty

To evaluate which parameters may affect endothelial cell loss after Descemet membrane endothelial keratoplasty (DMEK) by comparing eyes in the low vs high quartile of endothelial cell loss over a follow-up period of 4 years. Retrospective cohort study. Donor endothelial cell density (ECD) decline was evaluated for 351 eyes of 275 patients up to 4 years after DMEK for Fuchs endothelial corneal dystrophy (FECD). Eyes with a postoperative endothelial cell loss in the lower quartile at all available follow-up moments were assigned to Group 1 (n= 51) and those in the upper quartile to Group 2 (n= 42). Multinomial regression was used to assess which covariates were related to greater ECD decline. Mean endothelial cell loss as compared to preoperative donor ECD for the entire study group was 33 (±16)%, 36 (±17)%, and 52 (±18)% at 1, 6, and 48months postoperatively. Endothelial cell loss of Group 1 was 12 (±7)%, 13 (±6)%, and 26 (±8)% at, respectively, 1, 6, and 48months postoperatively, and 59 (±10)%, 64 (±9)%, and 75 (±5)% in Group 2. Partial graft detachment, donor death cause cardiovascular/stroke (vs cancer), postoperative complications other than graft detachment, and severity of preoperative FECD (all P < .01) showed the strongest relation with greater ECD decline. DMEK eyes with a completely attached graft and operated in an early stage of FECD may show the lowest endothelial cell loss postoperatively.

Descemet Membrane Endothelial Keratoplasty Versus Descemet Stripping Automated Endothelial Keratoplasty and Penetrating Keratoplasty

To compare the long-term graft survival outcomes and complications of patients who underwent Descemet membrane endothelial keratoplasty (DMEK), Descemet stripping automated endothelial keratoplasty (DSAEK), and penetrating keratoplasty (PK) for Fuchs endothelial corneal dystrophy (FECD) and bullous keratopathy (BK). Retrospective comparative cohort study. Patients with FECD and BK who underwent DMEK (121 eyes), DSAEK (423 eyes), or PK (405 eyes) from the prospective cohort from the Singapore Corneal Transplant Registry were included. A Kaplan-Meier survival analysis was conducted to compare the survival probabilities of the 3 groups. The main outcome measure was graft survival. The DMEK group had the best overall cumulative graft survival of 97.4%, compared to DSAEK (78.4%) and PK (54.6%) (P < .001). In eyes with FECD, the DMEK group had the best graft survival of 98.7% compared to DSAEK (96.2%) and PK (73.5%) (P= .009). The graft survival in eyes with BK was poorer overall; however, the DMEK group still had the best graft survival of 94.7%, compared to DSAEK (65.1%) and PK (47.0%, P= .001). Eyes that underwent DMEK had the lowest rate of graft rejection (1.7% vs DSAEK 5.0% vs PK 14.1%, P < .001) and postoperative elevation of intraocular pressure (11.6% vs DSAEK 23.6% vs PK 22.5%, P= .015). Patients who underwent DMEK for FECD and BK had better graft survival compared to DSAEK and PK. Eyes that underwent DMEK also had a significantly lower rate of graft rejection and elevated intraocular pressure compared to DSAEK and PK for the same indications.

Therapeutic Challenges and Prognosis of Descemet's Membrane Endothelial Keratoplasty in Herpes Simplex Eye Disease

To describe the functional outcome, postoperative complications, and complication management of Descemet's membrane endothelial keratoplasty (DMEK) in corneal decompensation secondary to Herpes simplex eye disease (HED). This retrospective interventional case series included 17 eyes that received DMEK for endothelial decompensation secondary to HED. Complete ophthalmological examination, including corrected-distance visual acuity (CDVA), anterior segment slit-lamp, and optical coherence tomography assessment, were performed preoperatively and postoperatively at regular follow-up intervals. Visual outcome and complication rates were compared with those of 72 consecutive eyes that received DMEK for Fuchs endothelial corneal dystrophy (FECD) and pseudophakic bullous keratopathy (PBK) during the same period. Mean follow-up time was 11.1 ± 5.9 months (range 6-27). CDVA improved from 1.16 ± 0.46 logMAR to 0.62 ± 0.44 logMAR (P = 0.001). Corneal pachymetry significantly decreased from 695 ± 53 μm at day 1 to 569 ± 88 μm at 2 months (P < 0.001). Postoperative complications occurred in 12 eyes, including primary graft failure (12%), endotheliitis (29%), corneal ulcers (35%), and cystoid macular edema (18%). Most complications occurred shortly after surgery, with a median delay of 2.5 months. In comparison, the complication rates for DMEK in FECD and PBK were significantly lower (no graft failure, P = 0.005; no endotheliitis, P < 0.001; no corneal ulcers, P < 0.001 and 3% cystoid macular edema, P = 0.046). DMEK surgery significantly improved CDVA in patients with endothelial decompensation due to HED. The rate of postoperative complications was higher than for FECD and PBK. Close follow-up is mandatory and the rate of postoperative inflammatory events suggests that patients should be kept on high doses of oral valacyclovir.

„Descemet membrane endothelial keratoplasty“ in komplexen Augen

Descemet membrane endothelial keratoplasty (DMEK) has become the standard surgical treatment for Fuchs' endothelial corneal dystrophy (FECD) in Germany. In addition to classical FECD, there are endothelial disorders amenable to DMEK associated with complex changes in the anterior segment of the eye, such as anterior synechia of the iris, larger iris defects, after glaucoma surgery, after vitrectomy and after trauma. This article provides an overview of the possibilities to treat patients with complex anterior segment situations in the presence of corneal endothelial decompensation with DMEK. Description of problems and current surgical techniques when performing DMEK in complex situations. Reconstruction of the iris or the iris/lens diaphragm often needs to be performed either simultaneously or in aprevious operation to treat patients with complex anterior segment alterations with DMEK. Both very shallow and very deep anterior chambers pose amajor problem. A DMEK graft from older donors (above 70years) is prone to less rolling and should be preferred in patients with adeep anterior chamber (e.g. after vitrectomy). The graft size should also be adapted to the available space, e. g. asmaller graft diameter should be selected for eyes with anterior synechia. There are only afew evaluations of DMEK under complex conditions; however, it appears that the rate of secondary graft failure, endothelial cell loss and the rebubbling rate are increased in this very heterogeneous group of diseases. Further studies are needed to identify risk factors for anegative progression after DMEK in "complex" eyes.

Outcomes of Hemi-Descemet Membrane Endothelial Keratoplasty for Fuchs Endothelial Corneal Dystrophy.

To report the mid-term outcomes of hemi-Descemet membrane endothelial keratoplasty (hemi-DMEK) performed for Fuchs endothelial corneal dystrophy (FECD). In this prospective, interventional case series, we evaluated clinical outcomes of 10 eyes from 10 patients who underwent hemi-DMEK for FECD. Main outcome measures were best-corrected visual acuity (BCVA), endothelial cell density (ECD), central pachymetry, and postoperative complications. At 1 year postoperatively, 7/7 eyes (excluding 2 eyes with low visual potential) reached a BCVA of ≥20/40 (≥0.5), 6/7 (86%) ≥20/25 (≥0.8), 4/7 (57%) ≥20/20 (≥1.0), and 2/7 (29%) 20/17 (≥1.2). BCVA remained stable until 2 years postoperatively (P ≥ 0.05) and further improved thereafter (P < 0.05). Mean ECD decreased from 2740 (±180) cells/mm preoperatively to 850 (±300) cells/mm (n = 9) at 1 year (P ≤ 0.05) and showed an annual decrease of on average 6% to 7% thereafter (P ≥ 0.05 between consecutive follow-ups). Pachymetry decreased from preoperatively 745 (±153) μm to 533 (±63) μm (n = 9) and 527 (±35) μm (n = 8) at 1 and 3 years postoperatively, respectively. Within the first 6 postoperative months, 4/10 eyes underwent rebubbling for visually significant graft detachment. One eye received secondary circular DMEK for persistent graft detachment 1 month postoperatively; another eye developed secondary graft failure 2.5 years postoperatively, and 1 eye was suspected for an allograft reaction 1.5 years postoperatively. Hemi-DMEK may render visual outcomes comparable to those achieved by conventional DMEK. Despite low ECD counts by 6 months, ECD levels remain fairly stable thereafter. Hence, hemi-DMEK may become a potential alternative technique for treatment of FECD while increasing the yield of the endothelial tissue pool.

Two-Year Clinical Outcome of 500 Consecutive Cases Undergoing Descemet Membrane Endothelial Keratoplasty.

To evaluate the clinical outcome of 500 consecutive cases up to 2 years after Descemet membrane endothelial keratoplasty (DMEK) and to assess which parameters may have influenced the clinical outcome. From a group of 500 eyes (393 patients), which underwent DMEK for Fuchs endothelial corneal dystrophy (FECD), bullous keratopathy, failed corneal transplants and other indications, clinical outcomes [best-corrected visual acuity (BCVA), central endothelial cell density (ECD), and central corneal thickness] were evaluated before, and at 6, 12, and 24 months after DMEK and postoperative complications were documented. At 12 months postoperatively, 81% of eyes reached a BCVA of ≥20/25 (≥0.8), 49% ≥20/20 (≥1.0), and 15% ≥20/18 (≥1.2) (n = 396) and remained stable up to 24 months (P = 0.828). Compared with preoperative ECD, mean postoperative ECD decreased by 37 (±18)%, 40 (±18)%, and 45 (±18)% at 6, 12, and 24 months, respectively (P < 0.05 for all time points). Surgery indication and graft attachment status were related to postoperative BCVA and ECD results. Eyes with FECD and attached grafts showed better BCVA outcomes and higher ECD (P < 0.05). Central corneal thickness decreased by 20 (±11)% to 525 (±46) μm from preoperative to 6 months postoperatively and remained stable thereafter (P > 0.05). Within the study period, retransplantation was required in 32 eyes (6.4%). Principal longer-term complications were secondary graft failure (1.4%) and allograft rejection (1.4%). Clinical outcomes remain excellent up to 2 years after DMEK, in particular for eyes operated on for FECD and with completely attached grafts.

Descemet Stripping Endothelial Keratoplasty for Fuchs' Endothelial Corneal Dystrophy: Five-Year Results of a Prospective Study

To determine 5-year outcomes of Descemet stripping endothelial keratoplasty (DSEK) for Fuchs' endothelial corneal dystrophy (FECD). Prospective cohort study. Fifty-two eyes of 45 subjects with FECD undergoing primary DSEK. Subjects were examined before and at fixed intervals through 60 months after DSEK. At each visit, graft survival was determined by slit-lamp examination; best spectacle-corrected visual acuity (BSCVA) was measured using the electronic Early Treatment Diabetic Retinopathy Study (ETDRS) protocol; total anterior corneal higher-order aberrations (HOAs) were derived from corneal topography; and corneal backscatter, corneal thickness, and endothelial cell density were measured from confocal microscopy images. Corneal thickness also was measured by ultrasonic pachymetry. Changes after DSEK were analyzed using generalized estimating equation models. Best-corrected visual acuity, HOAs, endothelial cell loss, corneal thickness, and corneal backscatter. Complete 60-month follow-up was possible in 34 eyes. Mean BSCVA±standard deviation improved from 0.45±0.19 logarithm of the minimum angle of resolution (logMAR) (Snellen equivalent, 20/56) before DSEK to0.09±0.13 logMAR (Snellen equivalent, 20/25) at 5 years (P < 0.001). Between 1 and 5 years, BSCVA improved by 0.06 logMAR (or 3 ETDRS letters; 95% confidence interval, 0.05-0.07 logMAR) per year (P < 0.001), and 56% of eyes were 0.1 logMAR (20/25) or better at 5 years. Graft thickness (approximately 155 μm) and corneal thickness (approximately 700 μm) did not change after surgery. Anterior corneal HOAs and backscatter decreased between 1 and 5 years (P ≤ 0.002). Six grafts failed, of which 4 were primary (iatrogenic); mean endothelial cell loss±standard deviation was 55±15% at 5 years. Between 1 and 5 years after DSEK, BSCVA continues to improve such that at 5 years, more than half of eyes see better than 20/25 with a mean total corneal thickness of 700 μm. Improvement in vision is accompanied by continued reduction in corneal haze and aberrations, suggesting ongoing remodeling of the cornea after restoration of endothelial function.