Phase-Sensitive Measurements of Depth-Dependent Signal Transduction in the Inner Plexiform Layer

Frontiers in Medicine

article

Clara Pfäffle¹  Hendrik Spahr¹  Katharina Gercke¹  Léo Puyo¹  Svea Höhl¹  David Melenberg¹  Yoko Miura¹  Gereon Hüttmann¹  Dierck Hillmann¹ 

[1] Institute of Biomedical Optic, University of Lübeck;Medical Laser Center Lübeck GmbH;Department of Ophthalmology, University of Lübeck;Airway Research Center North, Member of the German Center for Lung Research;Center of Brain, Behavior and Metabolism ,(CBBM), University of Lübeck;Thorlabs GmbH;Department of Physics, Vrije Universiteit Amsterdam

关键词: optoretinography;    optical coherence tomography;    phase-sensitive OCT;    functional imaging;    inner plexiform layer;    retina;   

DOI  :  10.3389/fmed.2022.885187

学科分类：社会科学、人文和艺术（综合）

来源: Frontiers

【 摘 要 】

Non-invasive spatially resolved functional imaging in the human retina has recently attracted considerable attention. Particularly functional imaging of bipolar and ganglion cells could aid in studying neuronal activity in humans, including an investigation of processes of the central nervous system. Recently, we imaged the activity of the inner neuronal layers by measuring nanometer-size changes of the cells within the inner plexiform layer (IPL) using phase-sensitive optical coherence tomography (OCT). In the IPL, there are connections between the neuronal cells that are dedicated to the processing of different aspects of the visual information, such as edges in the image or temporal changes. Still, so far, it was not possible to assign functional changes to single cells or cell classes in living humans, which is essential for studying the vision process. One characteristic of signal processing in the IPL is that different aspects of the visual impression are only processed in specific sub-layers (strata). Here, we present an investigation of these functional signals for three different sub-layers in the IPL with the aim to separate different properties of the visual signal processing. Whereas the inner depth-layer, closest to the ganglion cells, exhibits an increase in the optical path length, the outer depth-layer, closest to the bipolar cell layer, exhibits a decrease in the optical path length. Additionally, we found that the central depth is sensitive to temporal changes, showing a maximum response at a stimulation frequency of around 12.5 Hz. The results demonstrate that the signals from different cell types can be distinguished by phase-sensitive OCT.

【 授权许可】

CC BY