Mohammed Taariq, Tong Yuehong, Agee Julia, Challa Nayanika, Heintzmann Rainer, Hammer Martin, Curcio Christine A, Ach Thomas, Ablonczy Zsolt, Smith R Theodore
Department of Ophthalmology, New York University School of Medicine, New York, NY 10016, USA.
Department of Ophthalmology, Icahn School of Medicine of Mount Sinai, New York, NY 10029, USA.
Vision (Basel). 2018 Sep 26;2(4):38. doi: 10.3390/vision2040038.
To characterize fluorophore signals from drusen and retinal pigment epithelium (RPE) and their changes in age related macular degeneration (AMD), the authors describe advances in ex vivo hyperspectral autofluorescence (AF) imaging of human eye tissue. Ten RPE flatmounts from eyes with AMD and 10 from eyes without AMD underwent 40× hyperspectral AF microscopic imaging. The number of excitation wavelengths tested was initially two (436 nm and 480 nm), then increased to three (436 nm, 480 nm, and 505 nm). Emission spectra were collected at 10 nm intervals from 420 nm to 720 nm. Non-negative matrix factorization (NMF) algorithms decomposed the hyperspectral images into individual emission spectra and their spatial abundances. These include three distinguishable spectra for RPE fluorophores (S1, S2, and S3) in both AMD and non-AMD eyes, a spectrum for drusen (SDr) only in AMD eyes, and a Bruch's membrane spectrum that was detectable in normal eyes. Simultaneous analysis of datacubes excited atthree excitation wavelengths revealed more detailed spatial localization of the RPE spectra and SDr within drusen than exciting only at two wavelengths. Within AMD and non-AMD groups, two different NMF initialization methods were tested on each group and converged to qualitatively similar spectra. In AMD, the peaks of the SDr at ~510 nm (436 nm excitation) were particularly consistent. Between AMD and non-AMD groups, corresponding spectra in common, S1, S2, and S3, also had similar peak locations and shapes, but with some differences and further characterization warranted.
为了表征玻璃膜疣和视网膜色素上皮（RPE）的荧光团信号及其在年龄相关性黄斑变性（AMD）中的变化，作者描述了人眼组织离体高光谱自发荧光（AF）成像技术的进展。对10例AMD患者的RPE平铺标本和10例非AMD患者的RPE平铺标本进行了40倍高光谱AF显微镜成像。最初测试的激发波长数量为两个（436nm和480nm），然后增加到三个（436nm、480nm和505nm）。从420nm到720nm以10nm间隔收集发射光谱。非负矩阵分解（NMF）算法将高光谱图像分解为单独的发射光谱及其空间丰度。这些包括AMD和非AMD眼中RPE荧光团的三种可区分光谱（S1、S2和S3）、仅在AMD眼中的玻璃膜疣光谱（SDr）以及在正常眼中可检测到的布鲁赫膜光谱。与仅在两个波长激发相比，同时分析在三个激发波长激发的数据立方体揭示了RPE光谱和玻璃膜疣内SDr更详细的空间定位。在AMD组和非AMD组中，对每组测试了两种不同的NMF初始化方法，并收敛到定性相似的光谱。在AMD中，SDr在~波长510nm（436nm激发）处的峰值特别一致。在AMD组和非AMD组之间，共同的相应光谱S1、S2和S3也具有相似的峰值位置和形状，但存在一些差异，需要进一步表征。
