Department of Ophthalmology and University Eye Hospital, Friedrich-Alexander University Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany.
Graefes Arch Clin Exp Ophthalmol. 2022 Apr;260(4):1171-1181. doi: 10.1007/s00417-021-05473-w. Epub 2021 Nov 25.
In the past, increased latencies of the blue-on-yellow pattern visually evoked potentials (BY-VEP), which predominantly originate in the koniocellular pathway, have proven to be a sensitive biomarker for early glaucoma. However, a complex experimental setup based on an optical bench was necessary to obtain these measurements because computer screens lack sufficient temporal, spatial, spectral, and luminance resolution. Here, we evaluated the diagnostic value of a novel setup based on a commercially available video projector.
BY-VEPs were recorded in 126 participants (42 healthy control participants, 12 patients with ocular hypertension, 17 with "preperimetric" glaucoma, and 55 with perimetric glaucoma). Stimuli were created with a video projector (DLP technology) by rear projection of a blue checkerboard pattern (460 nm) for 200 ms (onset) superimposed on a bright yellow background (574 nm), followed by an offset interval where only the background was active. Thus, predominantly S-cones were stimulated while L- and M-cone responses were suppressed by light adaptation. Times of stimulus onset to VEP onset-trough (N-peak time) and offset-peak (P-peak time) were analyzed after age-correction based on linear regression in the normal participants.
The resulting BY-VEPs were quite similar to those obtained in the past with the optical bench: pattern-onset generated a negative deflection of the VEP, whereas the offset-response was dominated by a positive component. N-peak times were significantly increased in glaucoma patients (preperimetric 136.1 ± 10 ms, p < 0.05; perimetric 153.1 ± 17.8 ms, p < 0.001) compared with normal participants (123.6 ± 7.7 ms). Furthermore, they were significantly correlated with disease severity as determined by visual field losses retinal nerve fiber thinning (Spearman R = -0.7, p < 0.001).
Video projectors can be used to create optical stimuli with high temporal and spatial resolution, thus potentially enabling sophisticated electrophysiological measurements in clinical practice. BY-VEPs based on such a projector had a high diagnostic value for detection of early glaucoma. Registration of study Registration site: www.
gov Trial registration number: NCT00494923.
过去，蓝色-黄色图形视觉诱发电位（BY-VEP）的潜伏期延长，主要起源于 koniocellular 通路，已被证明是早期青光眼的敏感生物标志物。然而，获得这些测量值需要基于光学工作台的复杂实验设置，因为计算机屏幕缺乏足够的时间、空间、光谱和亮度分辨率。在这里，我们评估了基于商用视频投影仪的新型设置的诊断价值。
在 126 名参与者（42 名健康对照参与者、12 名眼压升高患者、17 名“前期”青光眼患者和 55 名周边青光眼患者）中记录 BY-VEPs。通过后投影在明亮的黄色背景（574nm）上叠加蓝色棋盘格图案（460nm），持续 200ms（起始）来创建 BY-VEPs，随后是仅背景活跃的偏移间隔。因此，主要刺激 S-锥体，同时通过光适应抑制 L-和 M-锥体反应。根据正常参与者的线性回归，对年龄校正后的刺激起始到 VEP 起始-低谷（N-峰时间）和偏移-峰值（P-峰时间）进行分析。
得到的 BY-VEPs 与过去使用光学工作台获得的结果非常相似：图形起始产生 VEP 的负偏转，而偏移响应主要由正分量主导。青光眼患者的 N-峰时间显著增加（前期 136.1±10ms，p<0.05；周边 153.1±17.8ms，p<0.001）与正常参与者（123.6±7.7ms）相比。此外，它们与视野损失视网膜神经纤维变薄（Spearman R=-0.7，p<0.001）确定的疾病严重程度显著相关。
视频投影仪可用于创建具有高时间和空间分辨率的光学刺激，从而有可能在临床实践中实现复杂的电生理测量。基于该投影仪的 BY-VEP 对早期青光眼的检测具有很高的诊断价值。
NCT00494923
