Hunold Alexander, Ortega Daniela, Freitag Stefanie, Link Dietmar, Antal Andrea, Klee Sascha, Haueisen Jens
Institute of Biomedical Engineering and Informatics, TU Ilmenau, 98693 Ilmenau, Germany.
Research Group in Bioinstrumentation and Clinical Engineering, Universidad de Antioquia, Medellín 050010, Colombia.
Life (Basel). 2025 May 21;15(5):820. doi: 10.3390/life15050820.
In this study, the perception of phosphenes was used as a surrogate identifier for stimulation sites for use in retinal-degenerative diseases. We aimed to investigate the influence of adaptation, electrode montage, and direction of view on electrically induced phosphenes. We developed a practical methodology to assess non-invasive ocular electrical stimulation, addressing specific areas in the retina. Phosphene thresholds were identified under light and dark adaptation for non-invasive transorbital electrical stimulation. The location and extent characterized the morphology of electrically induced retinal phosphenes for five directions of view and for seven electrode montages in 62 participants. Our results indicated the lowest phosphene thresholds under light adaptation. Cumulative charts of phosphenes visualized the location of phosphene hot spots and their focality for the investigated directions of view and electrode montages. Under consistent light adaptation, we found changes in electrode montage generated stronger changes in the phosphenes' morphology and distribution. Adjusting the electrodes in the orbital vicinity was more effective than changing the direction of view to shift the phosphene hot spot location to a pathological region to induce neuronal activity there. In this study, we established the first practical methodology to adapt non-invasive transorbital electrical stimulation to address specific areas in the retina.
在本研究中，将光幻视的感知用作视网膜退行性疾病中刺激部位的替代标识符。我们旨在研究适应、电极蒙太奇和观察方向对电诱发光幻视的影响。我们开发了一种实用方法来评估非侵入性眼电刺激，针对视网膜的特定区域。在明适应和暗适应条件下确定了非侵入性经眶电刺激的光幻视阈值。在62名参与者中，针对五个观察方向和七种电极蒙太奇，通过位置和范围表征了电诱发视网膜光幻视的形态。我们的结果表明，明适应下光幻视阈值最低。光幻视的累积图表直观显示了所研究观察方向和电极蒙太奇的光幻视热点位置及其聚焦情况。在一致的明适应条件下，我们发现电极蒙太奇的变化在光幻视的形态和分布上产生了更强的变化。在眼眶附近调整电极比改变观察方向更有效地将光幻视热点位置转移到病理区域以诱导那里的神经元活动。在本研究中，我们建立了首个实用方法，使非侵入性经眶电刺激适应视网膜的特定区域。
