Department of Ophthalmology and Visual Sciences, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama.
State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.
Retina. 2020 Apr;40(4):618-631. doi: 10.1097/IAE.0000000000002657.
To clarify the role of subretinal drusenoid deposits (SDD; pseudodrusen) in the progression of age-related macular degeneration through high-resolution histology.
In 33 eyes of 32 donors (early age-related macular degeneration, n = 15; geographic atrophy, n = 9; neovascular age-related macular degeneration, n = 7; unremarkable, n = 2), and 2 eyes of 2 donors with in vivo multimodal imaging including optical coherence tomography, examples of SDD contacting photoreceptors were assessed.
Subretinal drusenoid deposits were granular extracellular deposits at the apical retinal pigment epithelium (RPE); the smallest were 4-µm wide. Outer segment (OS) fragments and RPE organelles appeared in some larger deposits. A continuum of photoreceptor degeneration included OS disruption, intrusion into inner segments, and disturbance of neurosensory retina. In a transition to outer retinal atrophy, SDD appeared to shrink, OS disappeared, inner segment shortened, and the outer nuclear layer thinned and became gliotic. Stage 1 SDD on optical coherence tomography correlated with displaced OS. Confluent and disintegrating Stage 2 to 3 SDD on optical coherence tomography and dot pseudodrusen by color fundus photography correlated with confluent deposits and ectopic RPE.
Subretinal drusenoid deposits may start at the RPE as granular, extracellular deposits. Photoreceptor OS, RPE organelles, and cell bodies may appear in some advanced deposits. A progression to atrophy associated with deposit diminution was confirmed. Findings support a biogenesis hypothesis of outer retinal lipid cycling.
通过高分辨率组织学阐明视网膜下类脂沉积（SDD；假性玻璃膜疣）在年龄相关性黄斑变性进展中的作用。
在 32 名供体的 33 只眼（早期年龄相关性黄斑变性，n = 15；地图样萎缩，n = 9；新生血管性年龄相关性黄斑变性，n = 7；无明显病变，n = 2）和 2 名供体的 2 只眼中，进行了体内多模态成像，包括光学相干断层扫描，评估了与光感受器接触的 SDD 示例。
视网膜下类脂沉积是位于视网膜色素上皮（RPE）顶端的颗粒状细胞外沉积物；最小的宽 4µm。一些较大的沉积物中出现了外节（OS）片段和 RPE 细胞器。包括 OS 破坏、向内节侵入以及感觉神经视网膜紊乱的光感受器退行性变连续体。在外视网膜萎缩的转变过程中，SDD 似乎缩小，OS 消失，内节缩短，外核层变薄并出现神经胶质化。光学相干断层扫描上的 1 期 SDD 与 OS 移位相关。光学相干断层扫描上的融合和崩解的 2 期至 3 期 SDD 和眼底彩色照相上的点假性玻璃膜疣与融合沉积物和异位 RPE 相关。
视网膜下类脂沉积可能从 RPE 开始形成颗粒状、细胞外沉积物。一些高级沉积物中可能出现 OS、RPE 细胞器和细胞体。证实了与沉积减少相关的萎缩进展。这些发现支持外视网膜脂质循环的生物发生假说。
