硬脑膜上微电极植入并记录家猫视皮层电活动

Recording visual cortex electrical activity through flexible microelectrode array implanted on duramater endocranium of cats

目的建立初级视皮层区硬脑膜上柔性微电极阵列记录视皮层电活动的方法,比较黑白棋盘格图形和黑白闪烁刺激在诱发视觉诱发电位(visual evoked potential,VEP)方面的差异。方法成年健康家猫5只,静脉持续麻醉,肌松、呼吸机人工通气,采用自行设计的柔性微电极阵列,微创植入并固定于视皮层定位区的硬脑膜上。比较无视觉刺激和有视觉刺激的视皮层电活动,验证是否能记录到VEP;给予闪光和图形视觉刺激,记录和比较视觉诱发电位的峰值和潜伏期。结果通过微创手术将微电极阵列植入并固定在视皮层定位区的硬脑膜外;在硬脑膜外微电极阵列可记录到有效VEP;黑白棋盘格图形刺激与黑白闪烁刺激相比,前者诱发的VEP谷峰值显著高于后者(P<0.01),而诱发的VEP波谷潜伏期较后者长(P<0.05),且波峰潜伏期则显著长于后者(P<0.01)。结论在视皮层定位区硬脑膜外首创的微创植入并固定柔性微电极阵列的方法适用性、重复性好,黑白棋盘格图形刺激优于黑白闪烁刺激,经硬脑膜外利用微电极阵列记录诱发电位是可行的。

Objective To establish a new experiment method for recording visual cortex electrical activity through flexible microelectrode array being implanted on the duramater endocranium above visual cortex,and compare the difference between the visual evoked potential（VEP） evoked by black and white flare and that evoked by black and white checker.Methods A total of 5 health adult cats of both sexes were anesthetized,and artificially ventilated by breathing machine.Then flexible microelectrode array designed by our group was implanted on the epidural area outside of visual cortex location region.The results of visual cortex electrical activity evoked by without any visual stimulus or with visual stimulus was compared in order to record VEP.Then flash（black and white flare,F） and graphic（black and white checker,P） visual stimuli were given to record VEPs.Results The microelectrode array was implanted on the epidural area outside of visual cortex location region by the minimally invasive surgery.Valid VEP records were obtained by flexible microelectrode array in the epidural area.The valley-peak value of P-VEP was higher than that of F-VEP（P〈0.01）.The delitescence of valley and peak of P-VEP was longer than that of F-VEP（P〈0.05,0.01）.Conclusion Our microinvasive surgery procedure to implant and fix flexible microelectrode array on the duramater endocranium above visual cortex is of good adaptivity and reproducibility.The array is feasible to record VEP.VEPs evoked by black and white checker stimuli is better than those by flash light stimuli.