[Outcomes of hemi-Descemet membrane endothelial keratoplasty and phacoemulsification for the treatment of primary Fuchs' endothelial corneal dystrophy combined with cataract]. / Rezul'taty transplantatsii destsemetovoi membrany s endoteliem i fakoemul'sifikatsii pri pervichnoi endotelial'noi distrofii rogovitsy Fuksa, sochetannoi s kataraktoi.

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.

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.

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.

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.

Phenotype and genotype of concurrent keratoconus and Fuchs endothelial corneal dystrophy.

PURPOSE: To characterise the phenotype and genotype of concurrent keratoconus and Fuchs endothelial corneal dystrophy (KC + FECD). METHODS: We recruited 20 patients with concurrent KC + FECD for a retrospective observational case series from the United Kingdom and the Czech Republic. We compared eight parameters of corneal shape (Pentacam, Oculus) with two groups of age-matched controls who had either isolated keratoconus (KC) or isolated FECD. We genotyped probands for an intronic triplet TCF4 repeat expansion (CTG18.1) and the ZEB1 variant c.1920G >T p.(Gln640His). RESULTS: The median age at diagnosis of patients with KC + FECD was 54 (interquartile range 46 to 66) years, with no evidence of KC progression (median follow-up 84 months, range 12 to 120 months). The mean (standard deviation (SD)) of the minimum corneal thickness, 493 (62.7) µm, was greater than eyes with KC, 458 (51.1) µm, but less than eyes with FECD, 590 (55.6) µm. Seven other parameters of corneal shape were more like KC than FECD. Seven (35%) probands with KC + FECD had a TCF4 repeat expansion of ≥50 compared to five controls with isolated FECD. The average of the largest TCF4 expansion in cases with KC + FECD (46 repeats, SD 36 repeats) was similar to the age-matched controls with isolated FECD (36 repeats, SD 28 repeats; p = 0.299). No patient with KC + FECD harboured the ZEB1 variant. CONCLUSIONS: The KC + FECD phenotype is consistent with KC but with superimposed stromal swelling from endothelial disease. The proportion of cases with a TCF4 expansion is similar in concurrent KC + FECD and age-matched controls with isolated FECD.

Detecting Subclinical Corneal Edema Using Corneal Thickness Mapping in Patients Presenting Fuchs Endothelial Corneal Dystrophy.

PURPOSE: To determine whether local corneal thickness changes observed with optical coherence tomography (OCT) can detect subclinical corneal edema in Fuchs endothelial corneal dystrophy (FECD). SETTING: Retrospective cohort study. METHODS: A series of patients presenting FECD who underwent cataract surgery alone (45 eyes) or with concomitant Descemet membrane endothelial keratoplasty (triple procedure; 117 eyes). The study reviewed medical records, collected the preoperative corneal thickness map and calculated the differences and ratio of corneal thickness measured at 5, 7, and 9 mm from the central corneal thickness. Area under the receiver operating characteristic curves (AUCs) were calculated and thresholds were selected to obtain a specificity of 90%. RESULTS: The median difference between 5- and 2-mm corneal thickness in the supra-nasal quadrant (∆5-2mmSN) was 38 µm (interquartile range 34-46) in the cataract group and 17 µm (2-38) in the triple procedure group (P < .001). The corneal thickness ratios of supra-nasal 5- to 2-mm (R5/2mmSN) and 7- to 2-mm (R7/2mmSN) were 1.07 (1.06-1.08) and 1.15 (1.13-1.17)] in the cataract group and 1.03 (1.00-1.06) and 1.09 (1.06-1.14) in the triple procedure group (P < .001). The probability of corneal edema was increased 7-fold with ∆5-2mm SN < 27 µm (AUC = 0.76) and 9.4- and 7.4-fold with R5/2mmSN and R7/2mmSN < 1.045 (AUC = 0.77) and 1.118 (AUC = 0.76), respectively. CONCLUSIONS: Local changes in corneal thickness may be useful in detecting preclinical corneal edema, especially in patients with FECD undergoing cataract surgery.

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

PURPOSE: To evaluate the outcome of Descemet Membrane Endothelial Keratoplasty (DMEK) in eyes with pre-existing glaucoma. DESIGN: In this retrospective, observational case series we included data of 150 consecutive DMEKs in eyes with pre-existing glaucoma of 150 patients after excluding data of the second treated eye of each patient and of re-DMEKs during follow-up. Cumulative incidences of IOP elevation (IOP > 21 mmHg or ≥ 10 mmHg increase in IOP from preoperative value), post-DMEK glaucoma (need of an additional intervention due to worsening of the IOP), graft rejection, and graft failure rate were analyzed using Kaplan-Meier survival analysis. COX regression analysis was used to evaluate independent risk factors. RESULTS: The 36-month cumulative incidence of IOP elevation was 53.5% [95 CI 43.5-63.5%] and of post-DMEK glaucoma 36.3% [95 CI 26.3-46.3%]. Graft rejection occurred with a 36-month cumulative incidence of 9.2% [CI 95% 2.3-16.1]. None of the analyzed risk factors increased the risk for the development of graft rejection. The 36-month cumulative incidence of graft failure was 16.6% [CI 95% 8.4-24.8]. Independent risk factors for graft failure were the indication for DMEK "status after graft failure" (n = 16) compared to Fuchs' dystrophy (n = 74) (p = 0.045, HR 8.511 [CI 95% 1.054-68.756]) and pre-existing filtrating surgery via glaucoma drainage device (GDD) (n = 10) compared to no surgery/iridectomy (n = 109) (p = 0.014, HR 6.273 [CI 95% 1.456-27.031]). CONCLUSION: The risks of postoperative complications (IOP elevation, post-DMEK glaucoma, graft rejection, and graft failure) in patients with pre-existing glaucoma are high. In particular, pre-existing filtrating surgery via GDD implantation-but not trabeculectomy-and DMEK after graft failure increase the risk of graft failure.

Surgical Management of Fuchs Endothelial Corneal Dystrophy: A Treatment Algorithm and Individual Patient Meta-Analysis of Descemet Stripping Only.

PURPOSE: This study aims to determine predictive factors for success of Descemet stripping only (DSO) in Fuchs corneal endothelial dystrophy and propose a DSO treatment algorithm. METHODS: Ovid MEDLINE, Embase, and Cochrane CENTRAL databases were searched to evaluate DSO case series, including combined phacoemulsification and DSO, and the use of Rho-kinase inhibitors (ROC-i). Our primary outcome was success of corneal clearance. Secondary outcomes included the time to corneal clearance, the postoperative endothelial cell count (ECC), and the impact of ROC-i. RESULTS: Sixty-eight cases were evaluated with a mean follow-up of 12.4 months. DSO corneal clearance was achieved in 85% (n = 58) with a mean time of 4.9 weeks for the ROC-i group compared with 10.1 weeks in the observation group (P < 0.0001). The mean central ECC postoperatively was higher in the ROC-i group compared with the observation group 1151 ± 245 versus 765 ± 169 cells/mm2, respectively (P < 0.018). The postoperative best-corrected visual acuity (BCVA) improved in 61 eyes (90%), with mean final BCVA of 0.17 (0.26) logMAR (P = 0.001), which was statistically significant compared with preoperative BCVA. Factors influencing success were 4-mm descemetorhexis size, a clear peripheral ECC with no clinical sequelae of decompensation or guttae, and a low central corneal thickness. No intraoperative complications were noted. The commonest postoperative complication was deep corneal stromal scars noted at the descemetorhexis edge (n = 9). CONCLUSIONS: DSO has a role in the treatment of a subset of patients with Fuchs corneal endothelial dystrophy and that adjuvant treatment with ROC-i may lead to faster corneal clearance.

Cataract surgery in patients with Fuchs' dystrophy and corneal decompensation indicated for Descemet's membrane endothelial keratoplasty.

The availability of corneal donor tissue is limited in most developing countries. This study evaluated whether patients with coexisting cataract and Fuchs' dystrophy with corneal decompensation awaiting Descemet's membrane endothelial keratoplasty (DMEK) benefited from phacoemulsification. This is a retrospective case-control study which included patients with Fuchs' dystrophy and evidence of corneal decompensation awaiting DMEK. Best-corrected visual acuity (BCVA) and central corneal thickness (CCT) were documented at baseline (pre-cataract surgery in the case group, or at the time of transplantation registry in the control group), 1-month and pre-DMEK. A total of 16 phakic patients with visually significant cataracts had cataract surgery during the study period, and 15 pseudophakic patients were included as controls. There was no significant difference with regard to BCVA at baseline, 1-month or pre-DMEK between the case and control groups. Similarly, no significant difference in CCT was found at baseline, 1-month or pre-DMEK. In the case group, 4 patients with improved visual acuity post-cataract surgery chose to defer DMEK. After stratification, statistical analysis showed significantly better BCVA in the deferred group (n = 4) at 1-month post-cataract surgery, compared to the DMEK group (n = 12) (0.21 ± 0.21 vs. 0.86 ± 0.29 LogMAR, P = 0.004). The other parameters, including baseline BCVA and CCT at any time point documented, were not statistically different. In conclusion, in patients with Fuchs' dystrophy and decompensated corneas awaiting transplantation, phacoemulsification did not lead to significant increase of corneal thickness nor deterioration of visual acuity. A few patients achieved satisfactory vision after cataract surgery and deferred endothelial keratoplasty.

[Morphological features of the cornea in eyes with pseudophakic bullous keratopathy and Fuchs endothelial corneal dystrophy]. / Morfologicheskie osobennosti rogovitsy pri psevdofakichnoi bulleznoi keratopatii i endotelial'noi distrofii Fuksa.

PURPOSE: To evaluate the morphological features of posterior corneal layers in pseudophakic bullous keratopathy (PBK) and Fuchs endothelial corneal dystrophy (FECD). MATERIAL AND METHOD: The study included 20 patients (20 eyes) aged 73.8±7.8 with PBK and 24 patients (25 eyes) aged 72.5±10.6 with FECD. Central corneal thickness was measured in all eyes before the surgery by anterior segment optical coherence tomography (AS-OCT, RTVue-100, Optovue, USA). All patients underwent corneal transplantation (DSAEK or DMEK). Postoperative donor graft status was assessed as attached or detached by AS-OCT (RTVue-100, Optovue, USA). Specimens of Descemet's membranes (DMs) were obtained intraoperatively and investigated histologically (hematoxylin and eosin staining). Morphometric analysis was performed using optical microscope Leica DM-2500 (Digital Color Camera Leica DFC295) and ImageScope M software. RESULTS: There was no difference in thickness of DMs' prenatal anterior banded layer (2.58±0.49 µm) and postnatal posterior non-banded layer (11.30±2.64 µm) between PBK and normal cornea. In FECD eyes, DM was significantly thickened by additional collagen layer and guttate excrescences (postnatal layer thickness - 16.62±4.34 µm). Morphological study of the DMs of patients with graft detachment in the early postoperative period revealed residual stromal collagen fibrils that were fixed to the area with dense extracellular matrix. CONCLUSION: The study shows that chronic corneal edema is associated with pathological morphological changes in the posterior corneal layers in PBK and FECD. Individual features of the dense extracellular matrix in the DMs may play a key role in the attachment of donor graft to the corneal stroma and affect the postoperative outcome.

Visual Function in Pseudophakic Eyes with Fuchs' Endothelial Corneal Dystrophy.

PURPOSE: To assess vision in pseudophakic eyes with Fuchs' endothelial corneal dystrophy (FECD) before the onset of clinically detectable corneal edema. DESIGN: Cross-sectional study. METHODS: Sixty-one otherwise healthy pseudophakic eyes of 38 subjects with FECD (without clinically detectable edema) and 17 otherwise healthy pseudophakic eyes of 9 subjects with normal corneas. Subjects underwent clinical examination to determine the morphologic distribution of guttae (severity grading). Standardized best-corrected high-contract and low-contrast (photopic and mesopic) visual acuity (HCVA, LCVA) and straylight were measured. Scheimpflug tomography posterior elevation and pachymetry maps were interpreted for 3 tomographic features of subclinical edema: loss of regular isopachs, displacement of the thinnest point of the cornea, and presence of posterior surface depression. RESULTS: In FECD without tomographic features of edema (ie, normal tomography patterns), HCVA, LCVA, and straylight did not differ from that of eyes with normal corneas (P ≥ .09); these eyes encompassed the full range of severity grading of guttae. In FECD with all 3 tomographic features of edema, the same parameters were worse compared with eyes with normal corneas (P ≤ .02). In FECD with 1 or 2 tomographic abnormalities, mesopic LCVA (P = .04) and straylight (P = .003) were worse compared with eyes with normal corneas. CONCLUSIONS: Impairment of vision was associated with the presence of tomographic edema in eyes with FECD. When tomography patterns were normal in FECD (ie, guttae were present without tomographic edema), visual acuity and straylight were normal, and therefore corneal surgical intervention would not typically be indicated to improve vision.

Descemet Membrane Endothelial Transfer (DMET) in Pseudophakic Bullous Keratopathy After DSEK-A Case Report and Review of Literature.

PURPOSE: The purpose of this study was to report a Descemet membrane endothelial transfer (DMET) in a patient with pseudophakic bullous keratopathy (PBK) who developed graft dislocation after manual Descemet stripping endothelial keratoplasty. METHODS: A 60-year-old man presented with defective vision in the left eye; after Descemet stripping endothelial keratoplasty, graft dislocation was noted 1 month after surgery. RESULTS: Corneal clarity was improving slowly over 3 months without any secondary surgical intervention. The mechanism of DMET and the review of literature were enunciated. CONCLUSIONS: DMET occurs commonly in eyes with Fuch endothelial dystrophy and rarely in patients with PBK. The mechanism of DMET in PBK probably occurs because of migration of the donor endothelial cells from partially attached Descemet stripping endothelial keratoplasty grafts to the host stroma, in contrast to Fuch endothelial dystrophy, where the endothelial cells from the periphery migrate to the center. Hence, waiting for spontaneous corneal clarity is pivotal because of DMET even in patients with PBK for at least 3 months.

Scheimpflug Versus Optical Coherence Tomography to Detect Subclinical Corneal Edema in Fuchs Endothelial Corneal Dystrophy.

PURPOSE: The purpose of this research was to compare the ability of Scheimpflug and anterior segment optical coherence tomography (OCT) in detecting subclinical corneal edema in patients with Fuchs endothelial corneal dystrophy (FECD) without clinical corneal edema. METHODS: In this single-center, consecutive case series, 47 eyes of 29 patients with FECD were analyzed. The main outcome measures were anterior/posterior keratometry and central/thinnest corneal thickness. The criteria for subclinical corneal edema were loss of regular isopachs, displacement of the thinnest point of the cornea, and presence of posterior surface depression. Tomographic analyses were performed using Scheimpflug imaging (Pentacam HR) and OCT (anterior segment swept-source optical coherence tomography). RESULTS: The measurement of the continuous variables revealed a significant difference between the 2 devices. The anterior curvature was steeper and the posterior curvature was flatter when measured with OCT ( P < 0.001). The OCT showed a lower central corneal thickness and thinnest corneal thickness ( P < 0.001). The agreement between both devices to detect subclinical corneal edema was high. The interdevice reliability for loss of parallel isopachs as measured by Cohen kappa coefficient was 0.84; for the displacement of the thinnest point of the cornea, it was 0.6, and for the focal posterior corneal surface depression, it was 0.62. Subclinical corneal edema was detected in 72.3% of the patients with both devices. In only 2 cases (4.3%), subclinical corneal edema was detected by one of the devices. CONCLUSIONS: Scheimpflug and OCT imaging were both able to detect tomographic patterns of subclinical corneal edema. Therefore, both devices can help decision-making, favoring early endothelial keratoplasty in symptomatic patients with FECD without clinical corneal edema.

Hyperosmolar Eye Drops for Diurnal Corneal Edema in Fuchs' Endothelial Dystrophy: A Double-Masked, Randomized Controlled Trial.

PURPOSE: The Eye Drops for Early Morning-Associated Swelling (EDEMAS) trial assessed the efficacy of hyperosmolar eye drops on corneal edema resolution. DESIGN: Double-masked, randomized controlled trial of hyperosmolar eye drops. PARTICIPANTS: Participants with Fuchs' dystrophy scheduled for Descemet membrane endothelial keratoplasty. METHODS: One eye was randomized to hyperosmolar eye drops (treatment); the fellow eye was randomized to artificial tears (placebo). After baseline examination in the afternoon, corneas were examined using Scheimpflug tomography after eye opening in the morning. Participants received eye drops twice. Imaging was repeated every 30 minutes up to 4 hours. MAIN OUTCOME MEASURES: Decrease in central corneal thickness 1 hour after eye opening (primary end point), corneal thickness, subjective visual function, glare, visual acuity, and adverse events (AEs) (secondary end points). RESULTS: A total of 68 participants received the allocated intervention (59 eyes received treatment; 55 eyes received placebo). All eyes had stromal edema; none had epithelial edema. Corneal thickness was 626 µm in the treatment arm and 622 µm in the placebo arm after eye opening, indicating an early morning edema compared with baseline of +21 µm and +24 µm, respectively. Decrease in corneal thickness after 1 hour was -10.5 µm in the treatment arm (95% confidence interval [CI], -12.8 to -8.2) and -11.2 µm (95% CI, -13.6 to -8.9) in the placebo arm (between-arm difference, 0.7 µm, 95% CI, -2.0 to 3.5; P = 0.59), indicating no clinically relevant effect of hyperosmolar eye drops on early morning corneal edema. Results were not compatible with a relevant treatment effect on corneal thickness, visual acuity, and glare over the entire course of the study. Increase in subjective visual function was less rapid in the treatment arm than in the placebo arm. Adverse events, most commonly burning after eye drop application, were more common with treatment (30 eyes) than placebo (1 eye; risk difference, 49 percentage points; 95% CI, 36-62). CONCLUSIONS: In this double-masked, randomized controlled trial, resolution of early morning stromal edema was not accelerated by hyperosmolar eye drops, which more frequently caused AEs. These results are not compatible with a clinically relevant effect of hyperosmolar eye drops and do not support their routine use.

Extracellular matrix changes in corneal opacification vary depending on etiology.

Purpose: The purpose of this study is to examine the expression of tenascin-C and matrilin-2 in three different disorders, which frequently require corneal transplantation. These pathological conditions include bullous keratopathy (BK), Fuchs' endothelial corneal dystrophy (FECD), and corneal scarring in herpetic keratitis. Methods: Histological sections of corneal buttons removed during keratoplasty were analyzed in BK (n = 20), FECD (n = 9), herpetic keratitis (n = 12), and cadaveric control (n = 10) groups with light microscopy following chromogenic immunohistochemistry. The sections were evaluated by three investigators, and semiquantitative scoring (0 to 3+) was applied according to standardized methods at 400X magnification. Each layer of the cornea was investigated; moreover, the stroma was subdivided into subepithelial, middle, and pre-Descemet's membrane areas for more detailed analysis. Results: Excessive epithelial and stromal expression of tenascin-C was identified in all investigated conditions; the results were most pronounced in the pre-Descemet's membrane. Regarding matrilin-2, when examined in BK, there was increased labeling intensity in the epithelium (p<0.001) and stromal layers (p<0.05), and a decrease in the endothelium (p<0.001). In the other investigated conditions, only a low degree of stromal localization (p<0.05) of matrilin-2 was detected. Conclusions: The expression of tenascin-C and matrilin-2 differs when examined in various corneal pathologies resulting in opacification. Both molecules seem to be involved in regeneration and wound healing of the corneal matrix in these diseases.

Diseases of the corneal endothelium.

The corneal endothelial monolayer and associated Descemet's membrane (DM) complex is a unique structure that plays an essential role in corneal function. Endothelial cells are neural crest derived cells that rest on a special extracellular matrix and play a major role in maintaining stromal hydration within a narrow physiologic range necessary for clear vision. A number of diseases affect the endothelial cells and DM complex and can impair corneal function and vision. This review addresses different human corneal endothelial diseases characterized by loss of endothelial function including: Fuchs endothelial corneal dystrophy (FECD), posterior polymorphous corneal dystrophy (PPCD), congenital hereditary endothelial dystrophy (CHED), bullous keratopathy, iridocorneal endothelial (ICE) syndrome, post-traumatic fibrous downgrowth, glaucoma and diabetes mellitus.

Fibrillar Layer as a Marker for Areas of Pronounced Corneal Endothelial Cell Loss in Advanced Fuchs Endothelial Corneal Dystrophy.

PURPOSE: We sought to assess the correlation of corneal endothelial cell (CEC) density to alterations of collagen composition of Descemet membrane (DM) in advanced Fuchs endothelial corneal dystrophy (FECD) and to image such changes by slit-lamp biomicroscopy in vivo. DESIGN: Prospective, observational consecutive case series. METHODS: Fifty eyes (50 subjects) with advanced FECD were enrolled. After slit-lamp biomicroscopy and corneal Scheimpflug imaging, the Descemet endothelium complex (DEC) was retrieved during DM endothelial keratoplasty (DMEK) surgery. The expression of collagens I, III, and IV (COL I, COL III, and COL IV) and corresponding CEC density were analyzed by immunofluorescence flat mount-staining. Presence, diameter and surface area of collagen expression, and CEC density served as the main outcome measures. RESULTS: Immunofluorescence staining revealed central coherent collagen positive areas (mean surface area = 10 mm2 ± 6 mm2) corresponding to a fibrillar layer burying the guttae of DM in 84% (42/50) of DECs. CEC density overlying the fibrillar layer compared with the periphery was significantly reduced (-54.8%, P < .0001) with a steep decline of CEC density at its borders. Subgroup analysis revealed that the fibrillar layer may be imaged by slit-lamp biomicroscopy in vivo with significant positive correlation of mean maximum diameter detected by slit-lamp biomicroscopy (dSL max = 4.1 mm ± 0.9 mm) and by immunofluorescence staining (dIF max = 4.7 mm ± 1.1 mm; r = 0.76; P = .001). CONCLUSION: A fibrillar layer with a clear geographic pattern marks areas of pronounced loss of CEC density in advanced FECD eyes and may be imaged by slit-lamp biomicroscopy in vivo.

Intrastromal Corneal Ring Segments Implantation and Descemet Membrane Endothelial Keratoplasty for Coexisting Keratoconus and Fuchs Endothelial Dystrophy.

PURPOSE: To report two cases of coexisting keratoconus and Fuchs endothelial dystrophy treated with intrastromal corneal ring segments (ICRS) implantation and Descemet membrane endothelial keratoplasty (DMEK). METHODS: Two patients with coexisting keratoconus and Fuchs endothelial dystrophy underwent ICRS implantation and DMEK, in a two-stage procedure. Follow-up evaluation included Scheimpflug tomography and optical coherence tomography. RESULTS: In both cases, ICRS implantation improved corneal topography and DMEK restored normal corneal thickness. Corrected distance visual acuity improved from 20/100 to 20/30 and from 20/60 to 20/25. Urrets-Zavalía syndrome was diagnosed in one case and addressed with colored contact lens fitting. CONCLUSIONS: Low vision resulting from coexisting keratoconus and Fuchs endothelial dystrophy might be addressed more selectively with posterior lamellar keratoplasty and ICRS implantation. Urrets-Zavalía syndrome must be considered a possible complication after DMEK, especially in patients with keratoconus. [J Refract Surg. 2020;36(10):703-706.].

Brillouin Microscopy Visualizes Centralized Corneal Edema in Fuchs Endothelial Dystrophy.

PURPOSE: To investigate the feasibility of using Brillouin microscopy for assessment of corneal edema in patients with Fuchs endothelial corneal dystrophy (FECD). Brillouin microscopy analyzes the frequency shift of light inelastically scattered by naturally occurring acoustic waves in a small volume of tissue. The resulting frequency shift is a measure of the local hydromechanical properties of the tissue. METHODS: Participants were scanned using a clinical Brillouin imaging system (780 nm laser, 5 mW), and a color-coded map of the mean Brillouin shift laterally across the corneal stroma was created. RESULTS: Brillouin maps of normal subjects (n = 8) were relatively homogeneous, whereas maps of patients with FECD (n = 7) exhibited significantly reduced Brillouin shifts (unpaired t test, P < 0.001) centrally. The mean difference of 83 MHz corresponds to approximately 3.9% higher water content (percentage difference in volume fraction) in central corneas of the FECD group relative to normal subjects. The Brillouin scan of a patient with FECD 1 month after Descemet membrane endothelial keratoplasty measured a 62 MHz increase in Brillouin shift relative to the preoperative level, indicating normalization of corneal hydration. CONCLUSIONS: All patients with FECD scanned exhibited a centralized reduction in Brillouin shift, distinct from the normal subjects measured and consistent with centralized edema characterized by pachymetry. Brillouin scans revealed substantially reduced water content after Descemet membrane endothelial keratoplasty. These results suggest that Brillouin microscopy could aid treatment planning and assessment of FECD. Moreover, corneal hydration mapping may be useful in understanding fluid pump function dynamics of the cornea and developing early interventions for FECD.