Different Risk Profiles for Progression of Nonproliferative Diabetic Retinopathy: A 2-Year Study.

INTRODUCTION: Characterization of 2-year progression of different risk phenotypes in eyes with mild and moderate nonproliferative diabetic retinopathy (NPDR) in type 2 diabetes (T2D). METHODS: A 2-year prospective longitudinal cohort study (CORDIS, NCT03696810) was conducted. Ophthalmological examinations were performed including best corrected visual acuity, color fundus photography and optical coherence tomography (OCT and OCTA). OCT metrics, central retinal thickness and ganglion cell layer + inner plexiform layer (GCL + IPL) thickness were analyzed. OCTA metrics, vessel density (VD), perfusion density (PD) and area of intercapillary spaces (AIS) were obtained from superficial and deep capillary plexus (SCP, DCP). Only phenotype C identified by decreased VD ≥ 2 SD of healthy controls and phenotype B identified by subclinical macular edema with decreased VD < 2 SD of healthy controls were included. RESULTS: One hundred twenty-two eyes from T2D individuals were included in study; 65 eyes (53%) were classified as phenotype B and 57 eyes (47%) as phenotype C. For phenotype B, progression was associated with thinning of the GCL + IPL (ETDRS 35, 1 year p = 0.013, 2 year p < 0.001; ETDRS 43-47, 2 year p = 0.003) and vessel closure involving mainly the DCP for both ETDRS grades (ETDRS 35, 1 year p = 0.025, 2 year p = 0.034; ETDRS 43-47, 1 year p = 0.011). For phenotype C there was also progressive thinning of the GCL + IPL (ETDRS 35, in both years p ≤ 0.001; ETDRS 43-47, 1 year p = 0.002, 2 year p = 0.001), with vessel closure involving mainly SCP (ETDRS 35, 1 year p = 0.012, 2 year p = 0.023 in full-retina), which appeared to stabilize at maximal values in ETDRS grade 43-47 at the end of 2 years. ETDRS severity changes at the end of the 2-year period showed that worsening was associated with phenotype C with changes involving predominantly the SCP (VD, p = 0.005; PD, p = 0.008; AIS, p = 0.005). CONCLUSIONS: Association between ETDRS classification of NPDR severity and identification of different risk phenotypes offers new perspective to predict disease progression in T2D individuals with NPDR.

Macular alterations after small-incision cataract surgery.

PURPOSE: To characterize macular edema that occurs after uneventful cataract surgery. SETTING: Centre of Ophthalmology, University Hospital, Institute of Biomedical Research on Light and Image, Faculty of Medicine, University of Coimbra, Coimbra, Portugal. METHODS: Thirty-two eyes of 32 patients had uneventful phacoemulsification with implantation of a foldable intraocular lens. Postoperatively, patients were examined at 3, 6, 12, and 30 weeks. The examinations included retinal leakage analysis (Zeiss CSLO), optical coherence tomography (Humphrey Instruments), and retinal thickness analysis (Talia Technology, Ltd.). Results were compared with those in a control group comprising healthy subjects. RESULTS: Increases in retinal thickness (ie, over the mean +/- 2 SD in the control group) reached a maximum at 6 weeks in 13 of 32 eyes (41%), after which recovery was progressive. At 30 weeks, all eyes had good visual acuity, but 7 eyes (22%) still had macular edema. The edema was located primarily in the central macular region. Leaking sites involving the vascular areas of the macula, which indicated areas of abnormal blood-retinal barrier permeability, were a frequent finding. The number of sites remained relatively stable during the first 12 weeks (88%) and decreased to 68% at 30 weeks, indicating a trend toward recovery. CONCLUSION: Macular edema after cataract surgery occurred primarily in the central region of the macula and was associated with the presence of leaking sites, which were located predominantly in the vascular regions of the central macula.

Three-year follow-up study of blood-retinal barrier and retinal thickness alterations in patients with type 2 diabetes mellitus and mild nonproliferative diabetic retinopathy.

OBJECTIVE: To examine the 3-year alterations of the blood-retinal barrier and changes in retinal thickness occurring in the macular region in 14 eyes of 14 patients with type 2 diabetes mellitus (DM) and mild nonproliferative diabetic retinopathy. METHODS: We classified 14 eyes of 14 patients with type 2 DM and mild nonproliferative diabetic retinopathy, as having disease levels 20 (microaneurysms only) or 35 (microaneurysm plus retinal hemorrhage[s] and/or hard exudates) of Wisconsin Card-Sorting Test grading, by using 7-field stereoscopic fundus photographs. We examined them 7 times at 6-month intervals, using fundus photography, fluorescein sodium angiography, the retinal leakage analyzer (RLA)-modified confocal scanning laser ophthalmoscope, and the retinal thickness analyzer. The retinal leakage and retinal thickness maps were aligned and integrated into 1 image. Data from the group of individuals with type 2 DM were compared with those of a healthy control population (n = 14; mean age, 48 years; age range, 42-55 years) to establish reference maps for the RLA and retinal thickness analyzers. RESULTS: Areas of abnormally increased fluorescein leakage were detected in all eyes examined at baseline. The sites of increased fluorescein leakage reached values as high as 483% above normal levels, but in 20 of the total 95 examinations performed, fluorescein leakage returned to normal levels. Every eye that showed reversal to normal levels of fluorescein leakage showed stabilization or a decrease in glycosylated hemoglobin A(1c) values at the same visit. When comparing the RLA-leaking sites among the 7 examinations, they remained, in general, in the same locations, but there was a clear fluctuation in the percentage of increases. No clear correlation was observed among the location of areas of increased retinal thickness and RLA-leaking sites, the number of microaneurysms, or the glycosylated hemoglobin A(1c) values. Microaneurysms on fundus photographs showed different cumulative incidences throughout the follow-up period in the different eyes. Associations between these different abnormalities suggest specific patterns of evolution of type 2 DM-related retinal disease. CONCLUSIONS: The dominant alteration in the retina of patients with type 2 DM and mild nonproliferative retinopathy is the presence of RLA-leaking sites. This damage seems to be reversible and directly associated with variations in glycemic metabolic control. Together with the intensity and persistence of RLA-leaking sites, the rates of microaneurysm accumulation and alterations of the foveal avascular zone may characterize different genetically based phenotypes of diabetic retinopathy.

Retinal thickness in eyes with mild nonproliferative retinopathy in patients with type 2 diabetes mellitus: comparison of measurements obtained by retinal thickness analysis and optical coherence tomography.

OBJECTIVE: To compare measurements of retinal thickness in eyes with mild nonproliferative retinopathy in patients with type 2 diabetes mellitus using 2 different techniques: the retinal thickness analyzer (RTA) and optical coherence tomography (OCT). METHODS: Twenty-eight eyes from 28 patients with type 2 diabetes mellitus and mild nonproliferative retinopathy were classified according to the Wisconsin grading system by 7-field stereoscopic fundus photography. Ten eyes were classified as level 10 (absence of visible lesions) and 18 as level 20 or 35 (minimal retinopathy). All eyes were examined by the RTA and OCT. Healthy populations were used to establish reference maps for the RTA (n = 14; mean age, 48 years; age range, 42-55 years) and OCT (n = 10; mean age, 56 years; age range, 43-68 years). Reference maps were computed using the means + 2 SDs of the values obtained for each location. Increases in thickness were computed as a percentage of increase over these reference maps. RESULTS: The RTA detected increases in thickness in 1 or more locations in 24 of the 28 diabetic eyes examined, whereas OCT detected increases in only 3 eyes. The percentages of increase detected by the RTA ranged from 0.3% to 73.5%, whereas OCT detected percentages of increase of 0.3% to 4.8%. CONCLUSION: Optical coherence tomography is less sensitive than the RTA in detecting localized increases in retinal thickness in the initial stages of diabetic retinal disease.