Challa Naveen Kumar, Alghamdi Waleed M, Alluwimi Muhammed S, Alshammeri Saleh
Department of Optometry, College of Applied Medical Sciences, Qassim University, Buraidah, AlQassim, Saudi Arabia.
Diabetes Metab Syndr Obes. 2025 Feb 6;18:363-372. doi: 10.2147/DMSO.S504882. eCollection 2025.
To assess and compare subclinical alterations in superficial capillary plexus vessel density (SCPVD) and retinal layers thickness in the macular region between individuals with type 2 diabetes mellitus (DM) and healthy controls.
Swept-source OCT images were obtained from 29 control subjects and 24 diabetic subjects. Macular thickness (MT), retinal nerve fiber layer (RNFL) thickness, and ganglion cell layer (GCL) thickness were measured in the central macula and four quadrants of macular region using a 6.0 × 6.0 mm radial macular scan centered on the fovea. OCTA acquisition included a 3.0 × 3.0 mm macular scan for the foveal avascular zone (FAZ) and a 4.5 × 4.5 mm macular scan for SCPVD. The FAZ was manually mapped at the SCP on OCTA images.
In diabetic subjects, the superficial capillary plexus vessel density (SCPVD) was significantly lower in both the central (P = 0.04) and inferior (P = 0.01) regions compared to the control group. Additionally, diabetic patients showed a significant reduction in temporal macular thickness (MT) and thinning of the ganglion cell layer (GCL) in all three quadrants except in the central and inferior macula (P < 0.05). There was also significant thinning of the superior macular retinal nerve fiber layer (RNFL) in diabetics compared to controls (P = 0.02). While the foveal avascular zone (FAZ) was larger in diabetic subjects, this difference was not statistically significant (P = 0.78). Duration of diabetes has shown a significantly high positive correlation (r = 0.77, P < 0.01) with superior macular VD.
The findings of this study suggest that the diabetic macula experiences significant ganglion cell layer (GCL) thinning and reduced superficial capillary plexus (SCP) vascular density even before the onset of clinical retinopathy. Swept-source OCT proves to be an essential tool for detecting these early changes in diabetic patients.
评估和比较2型糖尿病（DM）患者与健康对照者黄斑区浅表毛细血管丛血管密度（SCPVD）和视网膜各层厚度的亚临床改变。
对29名对照者和24名糖尿病患者进行扫频源光学相干断层扫描（OCT）成像。使用以黄斑中心凹为中心的6.0×6.0mm径向黄斑扫描，测量中央黄斑及黄斑区四个象限的黄斑厚度（MT）、视网膜神经纤维层（RNFL）厚度和神经节细胞层（GCL）厚度。OCT血管造影（OCTA）采集包括用于黄斑无血管区（FAZ）的3.0×3.0mm黄斑扫描和用于SCPVD的4.5×4.5mm黄斑扫描。在OCTA图像上手动绘制FAZ在浅表毛细血管丛（SCP）上的位置。
与对照组相比，糖尿病患者中央（P = 0.04）和下方（P = 0.01）区域的浅表毛细血管丛血管密度（SCPVD）显著降低。此外，糖尿病患者除中央和下方黄斑外，其余三个象限的颞侧黄斑厚度（MT）显著降低，神经节细胞层（GCL）变薄（P < 0.05）。与对照组相比，糖尿病患者上方黄斑视网膜神经纤维层（RNFL）也显著变薄（P = 0.02）。虽然糖尿病患者的黄斑无血管区（FAZ）较大，但差异无统计学意义（P = 0.78）。糖尿病病程与上方黄斑血管密度呈显著正相关（r = 0.77，P < 0.01）。
本研究结果表明，在临床视网膜病变发生之前，糖尿病黄斑就已出现明显的神经节细胞层（GCL）变薄和浅表毛细血管丛（SCP）血管密度降低。扫频源OCT被证明是检测糖尿病患者这些早期变化的重要工具。
