Search

Purpose To determine if Scheimpflug tomography can identify subclinical corneal edema in Fuchs endothelial corneal dystrophy (FECD), and to recommend a new classification of FECD for clinical practice and research. Design Cross-sectional study with follow-up of outcomes. Participants Ninety-three eyes from 57 subjects with a range of severity of FECD and 74 eyes from 40 subjects with normal corneas. Methods Corneas were clinically assessed for FECD and corneal edema by using slit-lamp biomicroscopy, and categorized as having clinically definite edema (obvious visible edema), being suspicious for subclinical edema (possible corneal thickening without obvious edema on slit-lamp examination), or not having edema (no clinical suspicion of edema). Tomographic pachymetry and elevation maps derived from Scheimpflug images were evaluated by 3 masked observers for specific features believed to be consistent with corneal edema. FECD clinical disease course and outcomes were reviewed from the time of Scheimpflug image acquisition to the last available follow-up. Main Outcome Measures Presence of tomographic features: (1) loss of parallel isopachs, (2) displacement of the thinnest point of the cornea, and (3) focal posterior corneal surface depression. Clinical outcomes included the change in central corneal thickness (CCT) and vision after endothelial keratoplasty (EK). Results The 3 specific tomographic features were all present in all FECD corneas with clinically definite edema (n = 15), in ≥81% of FECD corneas suspicious for subclinical edema (n = 16), in ≤42% of FECD corneas deemed not to have edema (n = 62), and in ≤5% of normal corneas (n = 74). Corneas suspicious for subclinical edema that subsequently underwent EK (n = 9) all had at least 2 of the tomographic features present before EK, and improvement in vision, CCT, and tomographic features after EK confirmed the presence of subclinical edema preoperatively. Conclusions Subclinical corneal edema in FECD can be detected by Scheimpflug tomography. We recommend classifying FECD corneas as having clinically definite edema (based on slit-lamp examination), subclinical edema (based on tomographic features without clinically definite edema), or no edema (no tomographic or slit-lamp features of edema). This classification is independent of CCT and should be considered when evaluating FECD eyes for cataract surgery or EK. [ABSTRACT FROM AUTHOR]

Purpose Measuring patient-reported visual disability in Fuchs' endothelial corneal dystrophy (FECD) may be helpful in determining when to intervene and for understanding the outcomes of intervention. In this study, we aimed to validate a new patient-reported visual disability questionnaire, the Visual Function and Corneal Health Status (V-FUCHS) instrument, in FECD before and after endothelial keratoplasty (EK). Design Cross-sectional study with instrument readministration at 6 weeks. Participants Patients with a range of severity of FECD, including after EK, and patients with healthy corneas. Methods The V-FUCHS instrument was developed based on patient interviews, expert consultations, and pretesting. Psychometric methods of classic test theory were applied to estimate reliability and validity, including testing V-FUCHS against Catquest-9SF, a cataract-specific visual disability questionnaire. Ordered polytomous Rasch-based partial credit models and item response theory diagnostics were used to define the response patterns. Main Outcome Measures Reliability (primary) and validity (secondary). Results The final instrument was completed by 65% of patients with a range of severity of FECD (n = 41), after undergoing EK for FECD (n = 70), and with healthy corneas (n = 28). Participants were phakic or pseudophakic. Exploratory factor analysis among FECD and patients who underwent EK showed 2 independent factors of visual disability: 7 items related to visual acuity and 8 items related to glare or diurnal variation. Retest reliability was substantial (intraclass correlation coefficient, ≥0.8, both factors). Among all patients, the visual acuity factor was correlated with Catquest-9SF scores (r = 0.65; P < 0.001; n = 96). The glare or diurnal variation factor increased with FECD severity (P < 0.001, n = 69) and was higher in FECD than healthy participants (P < 0.001). Diagnostics revealed that both factors were well calibrated and met Rasch model expectations. Conclusions The V-FUCHS instrument is valid and reliable for assessing visual disability in FECD. The instrument allows for standardized, comprehensive, and rapid assessment of disease-specific visual disability and may be useful in clinical practice and research as a patient-reported outcome measure. [ABSTRACT FROM AUTHOR]

Purpose To determine 5-year outcomes of Descemet stripping endothelial keratoplasty (DSEK) for Fuchs' endothelial corneal dystrophy (FECD). Design Prospective cohort study. Participants Fifty-two eyes of 45 subjects with FECD undergoing primary DSEK. Methods 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. Main Outcome Measures Best-corrected visual acuity, HOAs, endothelial cell loss, corneal thickness, and corneal backscatter. Results 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 to 0.09±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. Conclusions 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. [ABSTRACT FROM AUTHOR]

Purpose Suboptimal visual acuity after endothelial keratoplasty has been attributed to increased anterior corneal high-order aberrations (HOAs). In this study, we determined anterior and posterior corneal HOAs over a range of severity of Fuchs' endothelial corneal dystrophy (FECD). Design Cross-sectional study. Participants A total of 108 eyes (62 subjects) with a range of severity of FECD and 71 normal eyes (38 subjects). Methods All corneas were examined by using slit-lamp biomicroscopy to determine the severity of FECD versus normality. Fuchs' endothelial corneal dystrophy corneas were categorized as mild, moderate, or advanced according to the area and confluence of guttae and the presence of clinically visible edema. Normal corneas were devoid of any guttae. Wavefront errors from the anterior and posterior corneal surfaces were derived from Scheimpflug images and expressed as Zernike polynomials through the sixth order over a 6-mm diameter optical zone. Backscatter from the anterior 120 μm and posterior 60 μm of the cornea also was measured from Scheimpflug images and was standardized to a fixed scatter source. Variables were compared between FECD and control eyes by using generalized estimating equation models to adjust for age and correlation between fellow eyes. Main Outcome Measures High-order aberrations, expressed as root mean square of wavefront errors, and backscatter of the anterior and posterior cornea. Results Total anterior corneal HOAs were increased in moderate (0.61±0.27 μm, mean ± standard deviation; P = 0.01) and advanced (0.66±0.28 μm; P = 0.01) FECD compared with controls (0.47±0.16 μm). Total posterior corneal HOAs were increased in mild (0.22±0.09 μm; P = 0.017), moderate (0.22±0.08 μm; P < 0.001), and advanced (0.23±0.09 μm; P < 0.001) FECD compared with controls (0.16±0.03 μm). Anterior and posterior corneal backscatter were higher for all severities of FECD compared with controls ( P ≤ 0.02, anterior; P ≤ 0.001, posterior). Conclusions Anterior and posterior corneal HOAs and backscatter are higher than normal even in early stages of FECD. The early onset of HOAs in FECD might contribute to the persistence of HOAs and incomplete visual rehabilitation after endothelial keratoplasty. [ABSTRACT FROM AUTHOR]

The Eye Drops for Early Morning-Associated Swelling (EDEMAS) trial assessed the efficacy of hyperosmolar eye drops on corneal edema resolution. Double-masked, randomized controlled trial of hyperosmolar eye drops. Participants with Fuchs' dystrophy scheduled for Descemet membrane endothelial keratoplasty. 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. 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). 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). 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. [ABSTRACT FROM AUTHOR]