Christensen U C, Kroyer K, Thomadsen J, Jorgensen T M, la Cour M, Sander B
Department of Ophthalmology, Glostrup Hospital, University of Copenhagen, Denmark.
Br J Ophthalmol. 2008 Jun;92(6):800-5. doi: 10.1136/bjo.2007.130500.
To present normative data of outer photoreceptor layer thickness obtained by a new semiautomatic image analysis algorithm operating on contrast-enhanced optical coherence tomography (OCT) images.
Eight Stratus OCT3 scans from identical retinal locations from 25 normal eyes were registered and combined to form a contrast-enhanced average image. Utilising the vertical intensity gradients of the enhanced OCT images to demarcate retinal layers, thickness measurements of the outer photoreceptor- and retinal pigment epithelium layer (RPE-OS(complex)) were obtained. Additionally backscattered light within the outer nuclear layer (ONL) in the fovea was registered and compared with backscattered light within the ONL in the peripheral part of the macula (I(ratio)-ONL).
The mean RPE-OS(complex) thickness in the foveal centre was 77.2 microm (SD = 3.95). The RPE-OS(complex) thickness in the superior macula 0.5-3 mm of the centre was significantly increased as compared with the corresponding inferior retina. In healthy subjects, the I(ratio)-ONL was 1.06.
Contrast-enhanced OCT images enable quantification of outer photoreceptor layer thickness, and normative values may help understanding better the relationship between functional outcome and photoreceptor morphology in retinal diseases.
呈现通过一种新的半自动图像分析算法对对比度增强光学相干断层扫描（OCT）图像进行分析所获得的外层光感受器层厚度的规范数据。
对来自25只正常眼睛相同视网膜位置的8次Stratus OCT3扫描进行配准并合并，以形成对比度增强的平均图像。利用增强型OCT图像的垂直强度梯度来划分视网膜层，获得外层光感受器和视网膜色素上皮层（RPE-OS（复合体））的厚度测量值。此外，记录了黄斑中心凹外核层（ONL）内的背向散射光，并与黄斑周边部分ONL内的背向散射光进行比较（I（比率）-ONL）。
黄斑中心凹处RPE-OS（复合体）的平均厚度为77.2微米（标准差=3.95）。与相应的下方视网膜相比，黄斑中心上方0.5-3毫米处的RPE-OS（复合体）厚度显著增加。在健康受试者中，I（比率）-ONL为1.06。
对比度增强的OCT图像能够对外层光感受器层厚度进行量化，规范值可能有助于更好地理解视网膜疾病中功能结果与光感受器形态之间的关系。
