Hadjikhani N, Sanchez Del Rio M, Wu O, Schwartz D, Bakker D, Fischl B, Kwong K K, Cutrer F M, Rosen B R, Tootell R B, Sorensen A G, Moskowitz M A
Nuclear Magnetic Resonance Center and Stroke and Neurovascular Laboratory, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA.
Proc Natl Acad Sci U S A. 2001 Apr 10;98(8):4687-92. doi: 10.1073/pnas.071582498. Epub 2001 Apr 3.
Cortical spreading depression (CSD) has been suggested to underlie migraine visual aura. However, it has been challenging to test this hypothesis in human cerebral cortex. Using high-field functional MRI with near-continuous recording during visual aura in three subjects, we observed blood oxygenation level-dependent (BOLD) signal changes that demonstrated at least eight characteristics of CSD, time-locked to percept/onset of the aura. Initially, a focal increase in BOLD signal (possibly reflecting vasodilation), developed within extrastriate cortex (area V3A). This BOLD change progressed contiguously and slowly (3.5 +/- 1.1 mm/min) over occipital cortex, congruent with the retinotopy of the visual percept. Following the same retinotopic progression, the BOLD signal then diminished (possibly reflecting vasoconstriction after the initial vasodilation), as did the BOLD response to visual activation. During periods with no visual stimulation, but while the subject was experiencing scintillations, BOLD signal followed the retinotopic progression of the visual percept. These data strongly suggest that an electrophysiological event such as CSD generates the aura in human visual cortex.
皮层扩散性抑制（CSD）被认为是偏头痛视觉先兆的基础。然而，在人类大脑皮层中验证这一假说一直具有挑战性。我们对三名受试者在视觉先兆期间进行了近乎连续记录的高场功能磁共振成像（MRI），观察到了与血氧水平依赖（BOLD）信号变化相关的情况，这些变化显示出至少八个CSD的特征，且与先兆的感知/发作时间同步。最初，在纹外皮层（V3A区）出现了BOLD信号的局灶性增加（可能反映血管舒张）。这种BOLD变化在枕叶皮层上连续且缓慢地进展（3.5±1.1毫米/分钟），与视觉感知的视网膜拓扑结构一致。沿着相同的视网膜拓扑进展，随后BOLD信号减弱（可能反映初始血管舒张后的血管收缩），对视觉激活的BOLD反应也减弱。在没有视觉刺激但受试者正在经历闪烁的期间，BOLD信号遵循视觉感知的视网膜拓扑进展。这些数据有力地表明，诸如CSD这样的电生理事件在人类视觉皮层中产生了先兆。
