Benoliel Tal, Raz Noa, Ben-Hur Tamir, Levin Netta
fMRI Lab, Neurology Department, Hadassah Hebrew University Medical Center, Jerusalem Israel.
Mult Scler. 2017 Feb;23(2):220-227. doi: 10.1177/1352458516649677. Epub 2016 Jul 11.
We have recently suggested that delayed visual evoked potential (VEP) latencies in the fellow eye (FE) of optic neuritis patients reflect a cortical adaptive process, to compensate for the delayed arrival of visual information via the affected eye (AE).
To define the cortical mechanism that underlies this adaptive process.
Cortical activations to moving stimuli and connectivity patterns within the visual network were tested using functional magnetic resonance imaging (MRI) in 11 recovered optic neuritis patients and in 11 matched controls.
Reduced cortical activation in early but not in higher visual areas was seen in both eyes, compared to controls. VEP latencies in the AEs inversely correlated with activation in motion-related visual cortices. Inter-eye differences in VEP latencies inversely correlated with cortical activation following FE stimulation, throughout the visual hierarchy. Functional correlation between visual regions was more pronounced in the FE compared with the AE.
The different correlation patterns between VEP latencies and cortical activation in the AE and FE support different pathophysiology of VEP prolongation in each eye. Similar cortical activation patterns in both eyes and the fact that stronger links between early and higher visual areas were found following FE stimulation suggest a cortical modulatory process in the FE.
我们最近提出，视神经炎患者对侧眼（FE）的视觉诱发电位（VEP）潜伏期延迟反映了一种皮质适应性过程，以补偿视觉信息通过患眼（AE）延迟到达。
确定这种适应性过程背后的皮质机制。
使用功能磁共振成像（MRI）对11名恢复的视神经炎患者和11名匹配的对照者进行测试，以检测对移动刺激的皮质激活和视觉网络内的连接模式。
与对照组相比，双眼早期视觉区域而非高级视觉区域的皮质激活减少。患眼的VEP潜伏期与运动相关视觉皮质的激活呈负相关。在整个视觉层次结构中，对侧眼VEP潜伏期的眼间差异与对侧眼刺激后的皮质激活呈负相关。与患眼相比，对侧眼视觉区域之间的功能相关性更明显。
患眼和对侧眼VEP潜伏期与皮质激活之间不同的相关模式支持每只眼中VEP延长的不同病理生理学。双眼相似的皮质激活模式以及在对侧眼刺激后早期和高级视觉区域之间发现更强连接的事实表明对侧眼存在皮质调节过程。
