目的：分析视网膜前巨噬细胞样细胞（epiretinal macrophage-like cells，eMLC）和视网膜脉络膜血流在急性黄斑神经视网膜病变（acute macular neuroretinopathy，AMN）患眼的临床特征。方法：回顾性分析2022年12月—2023年5月在中山大学中山眼科中心就诊的病程2周内的AMN患者21例（37眼）及年龄匹配的健康对照组33例（38眼）的临床资料。通过黄斑区内界膜上3 μm的en face 光学相干断层扫描（optical coherence tomography，OCT）分层信息对eMLC进行半自动分析提取和定量，同时测量OCT血管成像（optical coherence tomography angiography，OCTA）6 mm² x 6 mm²的黄斑区域内视网膜脉络膜血流参数进行分析对比。结果： AMN组黄斑区eMLC数量为（329.78±77.38）个，密度为（9.16±2.15）个/mm²，均较对照组（202.63±41.72）个、（5.63±1.16个/mm²）增加（均P＜0.001）。AMN组浅层和深层视网膜血流密度分别为（33.00±6.49）（32.59±7.41）%，均较对照组（36.18±5.63）（37.08±5.65）%减少（均P＜0.05）。视网膜全层中心凹无血管区（foveal avascular zone，FAZ）面积、视网膜全层血流密度、脉络膜毛细血管和脉络膜大中血管血流密度在两组间比较差异无统计学意义（P＞0.05）。浅层及深层视网膜血流密度和FAZ面积对eMLC密度无影响（P＞0.05）。13例AMN患者（23眼）1个月时的随访资料显示：AMN组末次随访时eMLC数量为（248.70±59.88）个、密度为（6.91±1.66）个/mm²较初次就诊时（307.87±82.98）个和（8.55±2.30）个/mm²减少（均P＜0.001），但仍高于同期对照组（176.58±27.89）个和（4.91±0.77）个/mm²（均P＜0.001）。视网膜和脉络膜血流参数较初次就诊时比较差异无统计学意义（均P＞0.05）。结论：AMN患眼中eMLC异常增多和聚集，同时存在轻度的视网膜血流密度下降，但无脉络膜血流参数变化，且eMLC变化与AMN病程相关但与视网膜血流变化无关，提示eMLC所代表的炎症可能独立参与了AMN的发生。

Objective: To investigate the clinical characteristics of epiretinal macrophage-like cells (eMLC) and retinochoroidal blood flow in eyes affected by acute macular neuroretinopathy (AMN). Methods: This retrospective case series study included 21 (37 eyes) patients diagnosed with AMN and 28 (33 eyes) healthy age-matched subjects. A 3 mm En-face optical coherence tomography (OCT) slab on the inner limiting membrane of the macular region was used to visualize and binarize the MLCs. The MLCs were binarized and quantified using a semiautomated method. Optical coherence tomography angiography (OCTA) was used to evaluate the perfusion status and obtain the structural data of macular within a 6 x 6 mm² macular region. Results: The number and density of macular eMLC in AMN eyes were significantly increased in comparison to control eyes: 329.78±77.38 vs. 202.63±41.72, (P＜0.001) and (9.16±2.15) cells/mm² vs. (5.63±1.16) cells/mm² (P＜0.001). In the macular region, both superficial and deep retinal vessel densities were significantly lower in the AMN eyes than in the control eyes: 33.00±6.49 vs. 36.18±5.63 (P=0.040); 32.59±7.41 vs. 37.08±5.65 (P=0.008). There were no significant differences in the vessel densities and foveal avascular zone (FAZ) area of full retina and choroidal vessel density between the two groups (P＞0.05). The eMLC density was not associated with the superficial and deep retinal FAZ area and vessel densities (all P＞0.05). At the one-month follow-up data of 13 patients (23 eyes), the number and density of macular eMLC were significantly lower in comparison to the initial visit: 248.70±59.88 vs. 307.87±82.98, P＜0.001 and (6.91±1.66) cells/mm² vs. (8.55±2.30) cells/mm² (P＜0.001). However, the number and density of macular eMLC are still noticeably higher than those of the control group during the same timeframe: 248.70±59.88 vs. 176.58±27.89 (P＜0.001) and (6.91±1.66) cells/mm² vs. (4.91±0.77) cells/mm² (P＜0.001). There was no significant difference in the vessel density of retina and choroidal during the follow-up (P＞0.05). Conclusions: The aggregation and activation of eMLC and a mild decrease in retinal blood flow density are observed in AMN, yet there is no corresponding shift in choroidal vessel density. The changes of eMLC are linked to the course of AMN, but they are not related to retinal vessel density. The inflammatory response represented by eMLC might independently contribute to the pathogenesis and progression of AMN.

巨噬细胞样细胞(macrophage-like cells, MLC)指起源、功能与巨噬细胞类似的免疫细胞，包括小胶质细胞、玻璃体细胞及巨噬细胞。将en face OCT显示层面设置在视网膜表明即可观测到视网膜表明的 MLC(epiretinal MLC, eMLC)，随后利用ImageJ软件即可对细胞进行提取和量化。研究表明，eMLC在炎症情况下均可出现细胞募集及活化现象，但在不同眼底病中各具特点。在糖尿病视网膜病变、视网膜静脉阻塞等视网膜缺血缺氧性疾病中，eMLC密度越高，黄斑水肿可能越严重。此外，eMLC密度更高的视网膜静脉阻塞患者抗VEGF疗效更差，视力预后不佳，提示基于en face OCT的eMLC不仅可用于评估视网膜炎情况，而且还能充当提示疾病疗效及预后的标志物。在葡萄膜炎等免疫炎症性疾病中，en face OCT亦可观测到eMLC密度、形态等改变。白塞病葡萄膜炎患者视网膜血管渗漏程度与eMLC密度相关性强，故eMLC密度可充当无创评估视网膜血管渗漏程度的新指标。然而，目前提取和量化eMLC的方法及标准不统一，降低了各研究间的可比性。因此，亟需制定统一的操作规范和评估标准。此外eMLC 所代表的具体细胞类型及功能仍需进一步探究。未来，研究者可以利用en face OCT对眼底炎症地进行无创评估。基于en face OCT的eMLC还能作为基础研究与临床研究之间的桥梁，为揭示疾病的致病机制提供重要参考。

Macrophage-like cells (MLC) refer to immune cells that originate from and function similarly to macrophages, including microglia, hyalocytes, and macrophages themselves. By setting the display level of en face OCT to the retinal surface, epiretinal MLC (eMLC) can be observed and subsequently extracted and quantified using ImageJ software. Studies indicate that eMLC can exhibit cell recruitment and activation in inflammatory conditions, each displaying distinct characteristics in different retinal diseases. In ischemic and hypoxic retinal conditions such as diabetic retinopathy and retinal vein occlusion, higher densities of eMLC are associated with more severe macularedema. Moreover, patients with retinal vein occlusion showing higher eMLC densities tend to have poorer responses to anti-VEGF treatments and worse visual prognoses, suggesting that eMLC identified via en face OCT can be used not only to assess retinal inflammation but also as biomarkers for disease efficacy and prognosis. In immune-inflammatory diseases like uveitis, changes in eMLC density and morphology can also be observed through en face OCT. Inpatients with Beh?et's disease, a strong correlation exists between the degree of retinal vascular leakage and eMLC density, making eMLC density a potential non-invasive marker for assessing retinal vascular leakage. However, the current methods and standards for extracting and quantifying eMLC are not unified, significantly reducing comparability between studies. Therefore, there is an urgent need to establish uniform operational protocols and assessment standards. Furthermore, the specific cell types and functions represented by eMLC observed via en face OCT require further investigation. In the future, en face OCT could be utilized for non-invasive assessment of retinal inflammation. eMLC based onen face OCT could also serve as a bridge between basic research and clinical studies, providing valuable insights into the pathogenic mechanisms of diseases.