It is unknown whether independent neural damage may occur in the pre-/absent vascular diabetic retinopathy (DR). To exclude vasculopathy, it is important to measure the integrity of the blood-retinal barrier (BRB). This cross-sectional study addressed this problem in type 1 diabetic patients with normal ocular fundus and absent breakdown of the BRB (confirmed with vitreous fluorometry). These were compared with a group with disrupted BRB (with normal fundus or initial DR) and normal controls. Multifocal electroretinography and chromatic/achromatic contrast sensitivity were measured in these 42 patients with preserved visual acuity. Amplitudes of neurophysiological responses (multifocal electroretinogram) were decreased in all eccentricity rings in both clinical groups, when compared with controls, with sensitivity >78% for a specificity level of 90%. Implicit time changes were also found in the absence of initial DR. Impaired contrast sensitivity along chromatic axes was also observed, and achromatic thresholds were also different between controls and both clinical groups. The pattern of changes in the group without baseline BRB permeability alterations, as probed by psychophysical and electrophysiological measurements, does thereby confirm independent damage mechanisms. We conclude that retinal neuronal changes can be diagnosed in type 1 diabetes, independently of the breakdown of the BRB and onset of vasculopathy.
Purpose To evaluate morphological and functional chorioretinal changes 5 years after standard photodynamic therapy (PDT) for chronic central serous chorioretinopathy (CSC). Methods A retrospective, nonrandomized study, including patients with chronic CSC treated with standard PDT and followed for at least 60 months. All patients underwent a complete ophthalmological examination, and the location and number of treatments were registered. Five or more years after treatment, subfoveal and non-subfoveal treated areas were evaluated with Spectralis optical coherence tomography and microperimetry. Results Seventeen eyes of 15 patients were included, with mean age of 48.3±8.4 years and a mean follow-up of 80.6± 12.4 months (range from 62 to 104 months). All eyes had neurosensory detachment (NSD) at baseline. Treatment was performed under the fovea in 58.8 % and in a non-foveal area in 41.2 % of the eyes. At the final visit all eyes had resolution of the NSD, with a statistical significant reduction in central macular thickness (p=0.005) and preserved neuroretinal thickness (p=0.839). There was a statistical difference between initial and final BCVA (p<0.001) and a mean gain of 8.4±7.8 letters. Subfoveal morphological changes in external limiting membrane (ELM) and in photoreceptor inner and outer segment junction (IS/OS) were correlated with final BCVA (p=0.015 and p=0.014 respectively), but not with the variation of BCVA. There was a statistical correlation between morphological changes in IS/OS line and retinal sensitivity in the central 12°and 2°(p=0.003 and p=0.002 respectively). The morphological changes in the subfoveal layers were not dependent on treatment location (p=0.154, p=0.644, and p=1.0 for ELM, IS/OS line, and retinal pigment epithelium respectively). Subfoveal final mean choroidal thickness was 295.1±68.7 μm, and showed no statistical difference from the normal population (p=0.633). Conclusions Morphological and functional chorioretinal changes, observed 5 or more years after standard PDT for chronic CSC, were not correlated with the location of treatment, neither with the progression of visual acuity or with the location of treatment, and are more likely to be related to the disease itself than with the treatment provided.
Purpose: To compare the efficacy and safety of intravitreal ranibizumab (IVR) in monotherapy or associated with panretinal photocoagulation (PRP) versus conventional PRP, for high-risk proliferative diabetic retinopathy (PDR) without vitreoretinal traction. Procedures: Multicenter randomized trial, with 3 treatment arms: PRP versus IVR alone and PRP + IVR combined treatment. Follow-up was performed at months 3, 6 and 12. Results: Thirty-five subjects were randomized and 32 used for analysis. Complete regression of neovessels elsewhere occurred in 100% (PRP + IVR), 75% (IVR) and 69.2% (PRP) and for neovessels of the disk in 44.4% (PRP + IVR), 37.5% (IVR) and 30.8% (PRP). During the 1-year duration of treatment, there was no need for laser rescue treatment in IVR-treated eyes. Conclusions: This trial suggests that the use of IVR is safe and may have a beneficial effect in the treatment of eyes with high-risk PDR. Message: Ranibizumab appears to have a place in the treatment of PDR.
Background To test whether a single or a composite set of macular vascular density parameters, evaluated with optical coherence tomography angiography (OCTA), are able to predict nonproliferative diabetic retinopathy (NPDR) staging according to the gold-standard ETDRS-grading scheme. Methods Prospectively defined, cross-sectional study in which macular structural and vascular parameters of diabetic eyes with nonproliferative DR (up to ETDRS Level 53) were evaluated with OCTA (Avanti RTVue-XR 100, Optovue Inc, Fremont, CA). Seven-field photographs of the fundus were taken for DR staging according to the ETDRS-grading scheme. The vessel density in the superficial and deep capillary plexus (SCP and DCP, respectively), as well as in the choriocapillaris (CC), were calculated using automated software. Univariate and multivariate ordered logistic regression models were used in the analysis. P < 0.05 was considered statistically significant. Results We included 101 eyes from 56 subjects (mean (SD) age 62.64 (11.74) years; 57.4% were male). On univariate analysis, several OCTA parameters were found to be associated with higher ETDRS level (parafoveal SCP density: OR = 0.87 (95% CI 0.76-0.99), p = 0.039; parafoveal DCP density: OR = 0.79 (95% CI 0.72-0.87), p < 0.001; CC density: OR = 0.89 (95% CI 0.80-0.99)), p = 0.036). In the final model, while also adjusting for relevant clinical features, only parafoveal vessel density in the DCP remained as a significant predictor of NPDR ETDRS level (OR = 0.54 (95% CI 0.32-0.92), p = 0.024). Conclusion Our results suggest that parafoveal vessel density in the DCP is the parameter most robustly associated with ETDRS level. OCTA analysis may provide objective imaging biomarkers to monitor NPDR clinical progression.
PurposeThe purpose of this study was to develop an algorithm to automatically standardize the brightness, contrast, and color balance of digital color fundus photographs used to grade AMD and to validate this algorithm by determining the effects of the standardization on image quality and disease grading. MethodsSeven-field color photographs of patients (>50 years) with any stage of AMD and a control group were acquired at two study sites, with either the Topcon TRC-50DX or Zeiss FF-450 Plus cameras. Field 2 photographs were analyzed. Pixel brightness values in the red, green, and blue (RGB) color channels were adjusted in custom-built software to make the mean brightness and contrast of the images equal to optimal values determined by the Age-Related Eye Disease Study (AREDS) 2 group.ResultsColor photographs of 370 eyes were analyzed. We found a wide range of brightness and contrast values in the images at baseline, even for those taken with the same camera. After processing, image brightness variability (brightest image–dimmest image in a color channel) was reduced 69-fold, 62-fold, and 96-fold for the RGB channels. Contrast variability was reduced 6-fold, 8-fold, and 13-fold, respectively, after adjustment. Of the 23% images considered nongradable before adjustment, only 5.7% remained nongradable.ConclusionsThis automated software enables rapid and accurate standardization of color photographs for AMD grading.Translational RelevanceThis work offers the potential to be the future of assessing and grading AMD from photos for clinical research and teleimaging.
Purpose: To study radial peripapillary capillary (RPC) density in the early stages of diabetic retinopathy (DR), using optical coherence tomography angiography. Methods: A cross-sectional evaluation of RPCs was performed using optical coherence tomography angiography (Avanti RTVue-XR 100, Optovue Inc, Fremont, CA). Annular RPC density was the primary outcome. Global density and retinal nerve fiber layer thickness were secondary outcomes. Diabetic eyes were divided into three groups: no DR, mild nonproliferative DR (mild NPDR), and moderate NPDR. Multilevel mixed-effects univariate and multivariate linear regression models were used. Results: We included 155 eyes (n = 42 control; n = 27 no DR; n = 28 mild NPDR; and n = 58 moderate NPDR) from 86 subjects (mean [SD] age 63.39 [10.70] years; 46.45% male). When compared with controls, a significant decrease in annular RPC density was found in all groups of diabetic eyes on multivariate analysis (no DR: β = −2.95, P < 0.001; mild NPDR: β = −1.76, P = 0.017; and moderate NPDR: β = −2.82, P < 0.001). We also detected a significant decrease in retinal nerve fiber layer thickness in diabetic eyes (even in the no DR group). Furthermore, in diabetic eyes, annular RPC density and retinal nerve fiber layer thickness correlated significantly (R = 0.4874, P < 0.001). Conclusion: Peripapillary neurovascular changes occur early in the course of DR. Their significance in the progression of DR warrants further research.
Purpose. To evaluate the contribution of the ocular risk factors in the conversion of the fellow eye of patients with unilateral exudative AMD, using a novel semiautomated grading system. Materials and Methods. Single-center, retrospective study including 89 consecutive patients with unilateral exudative AMD and ≥3 years of followup. Baseline color fundus photographs were graded using an innovative grading software, RetmarkerAMD (Critical Health SA). Results. The follow-up period was 60.9 ± 31.3 months. The occurrence of CNV was confirmed in 42 eyes (47.2%). The cumulative incidence of CNV was 23.6% at 2 years, 33.7% at 3 years, 39.3% at 5 years, and 47.2% at 10 years, with a mean annual incidence of 12.0% (95% CI = 0.088–0.162). The absolute number of drusen in the central 1000 and 3000 μm (P < 0.05) and the absolute number of drusen ≥125 µm in the central 3000 and 6000 µm (P < 0.05) proved to be significant risk factors for CNV. Conclusion. The use of quantitative variables in the determination of the OR of developing CNV allowed the establishment of significant risk factors for neovascularization. The long follow-up period and the innovative methodology reinforce the value of our results. This trial is registered with ClinicalTrials.gov NCT00801541.
Purpose: To evaluate long-term results and predictors of efficacy in patients with macular edema due to retinal vein occlusion (RVO) treated with intravitreal ranibizumab in a clinical practice setting. Methods: The clinical records of patients with a minimum follow-up of 3 years were retrospectively analyzed. Sixteen eyes with branch RVO (BRVO) and 16 with central RVO (CRVO) were included. All patients performed cross-sectional evaluation with best-corrected visual acuity (BCVA), spectral domain optical coherence tomography and fluorescein angiography. The foveal avascular zone (FAZ) was assessed and microstructural morphology of the retina was characterized. Results: Follow- up was 42.9 ± 9.0 and 44.8 ± 8.0 months in the CRVO and BRVO groups, respectively. Patients with CRVO received on average 6.9 injections, with a final VA gain of 8.3 ± 15.0 letters (p = 0.05). BRVO eyes had on average 5.9 injections, with a final VA gain of 1.6 ± 21.0 letters (p > 0.05). The FAZ area remained stable in both groups (p > 0.05). Baseline BCVA and disruption of the retinal pigment epithelium (RPE) were predictors of final BCVA (p = 0.001 and 0.011, respectively). Conclusion: Although functional outcomes were inferior to those reported in clinical trials, ranibizumab was satisfactory in the long-term treatment of macular edema secondary to RVO and was not associated with increased macular ischemia. Final BCVA depends on baseline BCVA and RPE integrity.
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