Shimada Y, Li Y, Bearse M A, Sutter E E, Fung W
Fujita Health University, Aichi, Japan.
Br J Ophthalmol. 2001 Apr;85(4):414-9. doi: 10.1136/bjo.85.4.414.
To assess early functional retinal changes in diabetics without retinopathy, a new multifocal stimulus paradigm was used that emphasises fast adaptive response contributions.
25 normal control subjects (25 eyes) and 11 diabetics without retinopathy (22 eyes) served as subjects. Stimulation and analysis were performed with Veris Science 4.0. A stimulation protocol was used that combines regular multifocal flicker stimulation with a periodic "global" flash inserted between the multifocal stimuli. The multifocal stimuli were presented four video frames apart. The global flash covered the entire screen in the third frame of the four frame interval. The remaining two frames were dark. The periodic global flashes could only contribute to the focal responses if they were affected by the multifocal stimulation. A non-linear component induced by the interaction of the focal and global flashes was observed. The differences between control subjects and diabetics were assessed in both the multifocal responses and their induced effect on the following global flashes.
The responses to focal flashes were reduced significantly in diabetics matched in age to the control subjects. The induced components showed large intersubject variability in controls and patients, and did not differ significantly between the two groups.
The periodic global flashes produce a greater multifocal response reduction in diabetics than in normals, indicating impairment in the rate or magnitude of recovery from the bright preceding stimulus. The new stimulation protocol reveals early changes in retinal function of diabetics.
为评估无视网膜病变的糖尿病患者早期视网膜功能变化，采用了一种强调快速适应性反应作用的新型多焦点刺激模式。
25名正常对照受试者（25只眼）和11名无视网膜病变的糖尿病患者（22只眼）作为研究对象。使用Veris Science 4.0进行刺激和分析。采用的刺激方案是将常规多焦点闪烁刺激与在多焦点刺激之间插入的周期性“整体”闪光相结合。多焦点刺激以相隔四个视频帧的方式呈现。整体闪光在四个帧间隔的第三帧中覆盖整个屏幕。其余两帧为黑屏。周期性整体闪光只有在受到多焦点刺激影响时才会对焦点反应产生作用。观察到焦点闪光与整体闪光相互作用诱发的非线性成分。在多焦点反应及其对后续整体闪光的诱发效应方面，对对照受试者和糖尿病患者之间的差异进行了评估。
在年龄与对照受试者匹配的糖尿病患者中，对焦点闪光的反应显著降低。诱发成分在对照组和患者中表现出较大的个体间变异性，两组之间无显著差异。
周期性整体闪光在糖尿病患者中比在正常人中产生更大的多焦点反应降低，表明从先前明亮刺激恢复的速率或幅度受损。新的刺激方案揭示了糖尿病患者视网膜功能的早期变化。
