AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal.
Faculty of Medicine, Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, Coimbra, Portugal.
Ophthalmic Res. 2023;66(1):228-237. doi: 10.1159/000526370. Epub 2022 Sep 28.
The aim of the study was to characterize the 2-year progression of risk phenotypes of nonproliferative diabetic retinopathy (NPDR) in type 2 diabetes (T2D) phenotype C, or ischemic phenotype, identified by decreased skeletonized retinal vessel density (VD), ≥2 SD over normal values, and phenotype B, or edema phenotype, identified by increased retinal thickness, i.e., subclinical macular edema, and no significant decrease in VD.
A prospective longitudinal cohort study (CORDIS, NCT03696810) was conducted with 4 visits (baseline, 6 months, 1 year, and 2 years). Ophthalmological examinations included best-corrected visual acuity, color fundus photography (CFP), and optical coherence tomography (OCT) and OCT angiography. Early Treatment Diabetic Retinopathy Study grading was performed at the baseline and last visits based on 7-field CFP.
One hundred and twenty-two eyes from T2D individuals with NPDR fitted in the categories of phenotypes B and C and completed the 2-year follow-up. Sixty-five (53%) of the eyes were classified as phenotype B and 57 (47%) eyes as phenotype C. Neurodegeneration represented by thinning of the ganglion cell layer and inner plexiform layer was present in both phenotypes and showed significant progression over the 2-year period (p < 0.001). In phenotype C, significant progression in the 2-year period was identified in decreased skeletonized VD (p = 0.01), whereas in phenotype B microvascular changes involved preferentially decrease in perfusion density (PD, p = 0.012). Phenotype B with changes in VD and PD (flow) and preferential involvement of the deep capillary plexus (p < 0.001) is associated with development of center-involved macular edema.
In the 2-year period of follow-up, both phenotypes B and C showed progression in retinal neurodegeneration, with changes at the microvascular level characterized by decreases in PD in phenotype B and decreases in VD in phenotype C.
本研究旨在描述 2 型糖尿病（T2D）患者中 C 型（缺血型）或 D 型（非灌注型）非增殖性糖尿病视网膜病变（NPDR）的风险表型在 2 年内的进展情况。这些表型通过视网膜血管密度（VD）减少、低于正常 2 个标准差来定义，或者通过视网膜厚度增加、即亚临床黄斑水肿且 VD 无明显下降来定义。
本前瞻性纵向队列研究（CORDIS，NCT03696810）共进行了 4 次访视（基线、6 个月、1 年和 2 年）。眼科检查包括最佳矫正视力、眼底彩色照相（CFP）、光学相干断层扫描（OCT）和 OCT 血管造影。根据 7 个视野的 CFP，在基线和最后一次访视时进行早期糖尿病视网膜病变治疗研究（ETDRS）分级。
共有 122 只患有 NPDR 的 T2D 个体的眼睛符合 B 型和 C 型表型的标准，并完成了 2 年的随访。其中 65 只（53%）眼睛被归类为 B 型，57 只（47%）眼睛被归类为 C 型。两种表型均存在神经退行性改变，表现为节细胞层和内丛状层变薄，且在 2 年内均有显著进展（p<0.001）。在 C 型表型中，2 年内的 VD 减少有显著进展（p=0.01），而在 B 型表型中，微血管改变主要涉及灌注密度（PD）的减少（p=0.012）。B 型表型的 VD 和 PD（血流）改变且主要涉及深层毛细血管丛（p<0.001）与中心性黄斑水肿的发生有关。
在 2 年的随访期间，B 型和 C 型表型均出现了视网膜神经退行性变的进展，微血管水平的变化特征为 B 型表型的 PD 减少和 C 型表型的 VD 减少。
