Correlation of Severity of Fuchs Endothelial Corneal Dystrophy With Triplet Repeat Expansion in TCF4.

IMPORTANCE: The CTG18.1 triplet repeat expansion in TCF4 has recently been found to be a common functional variant contributing significant risk to the development of Fuchs endothelial corneal dystrophy (FECD) in Eurasian populations. OBJECTIVES: To determine the effect of the expanded CTG18.1 allele of TCF4 on FECD severity and to correlate CTG triplet repeat allele length to the severity of FECD. DESIGN, SETTING, AND PARTICIPANTS: In a cross-sectional analysis, we studied 139 index cases (probands and unrelated individuals) with FECD recruited from a cornea referral practice at the University of Texas Southwestern Medical Center, Dallas, from April 2010 through February 2015. The triplet repeat polymorphism CTG18.1 was genotyped using a combination of short tandem repeat analysis, triplet repeat-primed polymerase chain reaction assay, and Southern blot analysis. Severity of FECD was graded using a modified Krachmer grading system (severity scale of 0-6 based on extent of confluent guttae). MAIN OUTCOMES AND MEASURES: The CTG triplet repeat length of the largest allele was compared with the Krachmer grade of FECD severity, keratoplasty proportion, and central corneal thickness in the white subset. RESULTS: Eighty-five of 122 white index cases with FECD (69.7%) harbored the triplet repeat expansion. The mean (SD) Krachmer grade was 5.61 (0.76) in the group with the repeat expansion compared with 5.11 (1.05) in the group without the expanded repeats (P = .01). Forty-seven participants with the repeat expansion (55.3%) had undergone keratoplasty at the time of recruitment, compared with 13 (35.1%) of those without the expansion (P = .0497). There was a positive correlation of Krachmer grade to triplet repeat number (P = .002) and a nominal association of the keratoplasty proportion with triplet repeat number (P = .04). The mean (SD) central corneal thickness was 605.9 (50.5) µm in the group with the expanded repeats compared with 581.3 (50.5) µm in the group without the expansion (P = .04). CONCLUSIONS AND RELEVANCE: The Krachmer grade of disease severity was greater in FECD cases with the CTG18.1 triplet repeat expansion in TCF4 than in those without the expansion. The CTG triplet repeat allele length was positively correlated with the Krachmer grade of severity. The TCF4 triplet repeat expansion resulted in a more severe form of FECD, with clinical and surgical therapeutic implications.

Association of Disorganization of Retinal Inner Layers With Vision After Resolution of Center-Involved Diabetic Macular Edema.

IMPORTANCE: Macular edema (ME) prognosis and treatment response vary according to the underlying abnormalities. Biomarkers of visual acuity (VA) improvement could influence management decisions in different types of ME. OBJECTIVE: To investigate whether disorganization of retinal inner layers (DRIL) and other spectral-domain optical coherence tomography (SD-OCT)-derived variables are associated with subsequent VA after ME resolution in both nondiabetic and diabetic ME. DESIGN, SETTING, AND PARTICIPANTS: A retrospective, longitudinal cohort study in which Snellen VA testing and SD-OCT macular imaging were performed, was conducted at a tertiary referral eye center for retinal diseases. The medical records of all patients with ME from December 1, 2010, to December 31, 2012, were reviewed. The date of the last follow-up was June 1, 2013. Participants included 55 patients (70 eyes) with center-involved ME that had resolved during an 8-month period. Patients were grouped based on the source of ME (diabetic vs nondiabetic). Exclusion criteria included significant media opacity interfering with good-quality SD-OCT image acquisition. Masked graders analyzed the central 1500-µm macular region for changes, including cysts, DRIL length and extent, and outer retinal layers disruption. Intragrader and intergrader agreement Spearman rank correlation coefficients ranged from 0.70 to 0.93 for quantitative measurement, and κ values ranged from 0.88 to 1.00 for qualitative grading. MAIN OUTCOMES AND MEASURES: Visual acuity and morphologic changes measured on SD-OCT. RESULTS: In both groups, VA after ME resolution correlated with baseline VA. In diabetic ME involving a multivariable model including baseline VA and DRIL, total length was associated with subsequent VA as determined by a parameter estimate (PE) of 0.0003 (95% CI, 0-0.0006) (P = .03). The VA change during the 8-month period, after adjusting for baseline VA, was best associated with DRIL change (PE, 0.0002 [95% CI, 0-0.0003]; P = .04). Participants whose DRIL resolved, both early and late, showed improvement in their VA deficit at 8 months (least squares mean [SE], 41.3 [28.5] and 40.9 [37.5], respectively) compared with nonresolvers, whether inconsistent or persistent, whose VA worsened. After adjustment for baseline VA, eyes with persistent DRIL showed the largest difference in VA deficit compared with those with no baseline DRIL (-89.6 [27.2] vs 49.7 [19.6], respectively; P = .006). CONCLUSIONS AND RELEVANCE: The presence of DRIL at baseline and its resolution pattern may be associated with subsequent VA after resolution of center-involved diabetic ME.

Neural Retinal Disorganization as a Robust Marker of Visual Acuity in Current and Resolved Diabetic Macular Edema.

Despite treatment advances, diabetic eye disease remains a leading cause of visual acuity (VA) loss worldwide. No methods to prospectively determine which patients will gain or lose vision exist, limiting individualized risk assessment and management. We investigated whether noninvasive, readily obtainable spectral domain optical coherence tomography parameters were correlated with VA in eyes with current or resolved center-involved diabetic macular edema (DME). Images were evaluated for disorganization of the retinal inner layers (DRIL), cysts, epiretinal membranes, microaneurysms, subretinal fluid, and outer layer disruption/reflectivity. DRIL affecting ≥50% of the 1-mm central retinal zone was associated with worse VA in all eyes, eyes with current edema, and eyes with resolved edema. Furthermore, early 4-month change in DRIL extent predicted VA change from baseline to 1 year. These data suggest that DRIL is a robust predictor of VA in eyes with present or previous DME and more highly correlated with VA than other widely used measures, such as retinal thickness. If further studies confirm DRIL as a predictive biomarker of future VA, physicians would gain a new tool of substantial clinical and investigative importance that could significantly change the approach to ophthalmic counseling and therapeutic management in patients with diabetes.

Peripheral lesions identified by mydriatic ultrawide field imaging: distribution and potential impact on diabetic retinopathy severity.

OBJECTIVE: To assess diabetic retinopathy (DR) as determined by lesions identified using mydriatic ultrawide field imaging (DiSLO200; Optos plc, Scotland, UK) compared with Early Treatment Diabetic Retinopathy Study (ETDRS) 7-standard field film photography. DESIGN: Prospective comparative study of DiSLO200, ETDRS 7-standard field film photographs, and dilated fundus examination (DFE). PARTICIPANTS: A total of 206 eyes of 103 diabetic patients selected to represent all levels of DR. METHODS: Subjects had DiSLO200, ETDRS 7-standard field film photographs, and DFE. Images were graded for severity and distribution of DR lesions. Discrepancies were adjudicated, and images were compared side by side. MAIN OUTCOME MEASURES: Distribution of hemorrhage and/or microaneurysm (H/Ma), venous beading (VB), intraretinal microvascular abnormality (IRMA), and new vessels elsewhere (NVE). Kappa (κ) and weighted κ statistics for agreement. RESULTS: The distribution of DR severity by ETDRS 7-standard field film photographs was no DR 12.5%; nonproliferative DR mild 22.5%, moderate 30%, and severe/very severe 8%; and proliferative DR 27%. Diabetic retinopathy severity between DiSLO200 and ETDRS film photographs matched in 80% of eyes (weighted κ = 0.74,κ = 0.84) and was within 1 level in 94.5% of eyes. DiSLO200 and DFE matched in 58.8% of eyes (weighted κ = 0.69,κ = 0.47) and were within 1 level in 91.2% of eyes. Forty eyes (20%) had DR severity discrepancies between DiSLO200 and ETDRS film photographs. The retinal lesions causing discrepancies were H/Ma 52%, IRMA 26%, NVE 17%, and VB 4%. Approximately one-third of H/Ma, IRMA, and NVE were predominantly outside ETDRS fields. Lesions identified on DiSLO200 but not ETDRS film photographs suggested a more severe DR level in 10% of eyes. Distribution in the temporal, superotemporal, inferotemporal, superonasal, and inferonasal fields was 77%, 72%, 61%, 65%, and 59% for H/Ma, respectively (P<0.0001); 22%, 24%, 21%, 28%, and 22% for VB, respectively (P = 0.009); 52%, 40%, 29%, 47%, and 36% for IRMA, respectively (P<0.0001), and 8%, 4%, 4%, 8%, and 5% for NVE, respectively (P = 0.03). All lesions were more frequent in the temporal fields compared with the nasal fields (P<0.0001). CONCLUSIONS: DiSLO200 images had substantial agreement with ETDRS film photographs and DFE in determining DR severity. On the basis of DiSLO200 images, significant nonuniform distribution of DR lesions was evident across the retina. The additional peripheral lesions identified by DiSLO200 in this cohort suggested a more severe assessment of DR in 10% of eyes than was suggested by the lesions within the ETDRS fields. However, the implications of peripheral lesions on DR progression within a specific ETDRS severity level over time are unknown and need to be evaluated prospectively.

Ultra-wide field retinal imaging in detection, classification, and management of diabetic retinopathy.

Current ultra-wide field (UWF) retinal imaging systems utilize scanning laser ophthalmoscope technology combined with an ellipsoidal mirror to capture up to 200 degrees of the retina in a single image. When compared with mydriatic ETDRS-protocol, 7 standard field photographs and clinical examination, nonmydriatic UWF images appear to have excellent agreement in allowing the detection and classification of diabetic retinopathy (DR), although larger, definitive validation studies are still forthcoming. UWF imaging and angiography allow visualization of peripheral retinal nonperfusion, vascular leakage and neovascularization in patients with DR that may not be captured on 7 standard fields. Prospective randomized controlled trials are needed to evaluate whether modified laser treatment algorithms based on improved visualization of the retinal periphery might improve patient outcomes. Nonmydriatic UWF imaging has potential applications for ocular diabetic telehealth programs, but validation of newer, more portable, and more affordable UWF imaging models is needed.