Felder Anthony E, Balasubramanian Giri, Arroyo Aldo, Park Jason C, Shahidi Mahnaz, McAnany J Jason
Richard and Loan Hill Department of Biomedical Engineering, University of Illinois Chicago, Chicago, IL, USA.
Ophthalmology and Visual Sciences, University of Illinois Chicago, Chicago, IL, USA.
Transl Vis Sci Technol. 2025 Jul 1;14(7):3. doi: 10.1167/tvst.14.7.3.
Flickering light stimulation induces functional hyperemia, characterized by vasodilation, blood flow augmentation, and venous oxygen elevation. We present a new method to investigate the frequency dependence of metrics associated with functional hyperemia.
A novel optical imaging system was developed to quantify retinal blood vessel diameter (D), oxygen saturation (SO2), and the inner retinal oxygen extraction fraction (OEF) before and after light flicker at different frequencies. Measurements were performed in 10 visually normal subjects (20-62 years) at flicker frequencies from 2 to 30 Hz. In addition, a measure of neural function was obtained by steady-state pattern electroretinography (ssPERG) across a similar range of frequencies.
Flicker stimulation greater than 2 Hz increased D, increased SO2 in veins, and decreased OEF. The maximum response for all metrics was obtained between 16 and 30 Hz, indicating that vascular and oxygenation metrics share a similar frequency response with light flicker. ssPERG amplitudes were positively correlated with flicker-induced increases in venous D and SO2. ssPERG amplitude was negatively correlated with flicker-induced decreases in OEF.
We present a novel retinal imaging method to evaluate the frequency dependence of changes in D, SO2, and OEF to light flicker stimulation. The relationship between these metrics and ssPERG amplitudes was evaluated.
The frequency-dependent response of retinal D, SO2, and OEF established in healthy individuals herein has the potential to serve as a biomarker of vascular and tissue abnormality in future studies of retinal disease.
闪烁光刺激可诱发功能性充血，其特征为血管舒张、血流量增加和静脉血氧升高。我们提出一种新方法来研究与功能性充血相关指标的频率依赖性。
开发了一种新型光学成像系统，用于量化不同频率光闪烁前后视网膜血管直径（D）、血氧饱和度（SO2）和视网膜内层氧提取分数（OEF）。对10名视力正常的受试者（20 - 62岁）在2至30赫兹的闪烁频率下进行测量。此外，通过稳态图形视网膜电图（ssPERG）在相似频率范围内获得神经功能指标。
大于2赫兹的闪烁刺激可增加血管直径（D）、静脉血氧饱和度（SO2）并降低氧提取分数（OEF）。所有指标的最大反应出现在16至30赫兹之间，表明血管和氧合指标与光闪烁具有相似的频率响应。ssPERG振幅与闪烁诱导的静脉血管直径（D）和血氧饱和度（SO2）增加呈正相关。ssPERG振幅与闪烁诱导的氧提取分数（OEF）降低呈负相关。
我们提出一种新型视网膜成像方法，以评估视网膜血管直径（D）、血氧饱和度（SO2）和氧提取分数（OEF）对光闪烁刺激变化的频率依赖性。评估了这些指标与ssPERG振幅之间的关系。
本文在健康个体中建立的视网膜血管直径（D）、血氧饱和度（SO2）和氧提取分数（OEF）的频率依赖性反应，有可能在未来视网膜疾病研究中作为血管和组织异常的生物标志物。
