Santangelo Roberto, Castoldi Valerio, D'Isa Raffaele, Marenna Silvia, Huang Su-Chun, Cursi Marco, Comi Giancarlo, Leocani Letizia
Department of Neurology and Institute of Experimental Neurology (INSPE) - IRCCS-San Raffaele Hospital, Via Olgettina 60, 20132, Milan, Italy.
University Vita-Salute San Raffaele - IRCCS-San Raffaele Hospital, Via Olgettina 60, 20132, Milan, Italy.
Doc Ophthalmol. 2018 Jun;136(3):165-175. doi: 10.1007/s10633-018-9630-5. Epub 2018 Apr 5.
Visual evoked potentials (VEPs) are a powerful tool to evaluate nervous conduction along the visual pathways, both in humans and in animal models. Traditionally, epidural screw electrodes are used to record VEPs in preclinical research. Here we tested the feasibility in the preclinical setting of the same noninvasive technique used for clinical VEP acquisition, by using epidermal cup electrodes with no surgical procedures.
Monocular flash VEPs were recorded bilaterally under sevoflurane anesthesia once a week for 6 weeks in 14 dark Agouti rats, 7 with implanted epidural screws and 7 with epidermal 6 mm Ø Ag/AgCl cups.
VEP traces obtained with the two techniques were morphologically comparable. There were no significant differences in latency of the main visual component between screw-recorded VEPs (sVEPs) and cup-recorded VEPs (cVEPs). Amplitude values with epidermal cups were significantly lower than those with epidural screws. Both techniques provided latencies and amplitudes which were stable over time. Furthermore, with regard to latency both methods ensured highly repeatable measurements over time, with epidermal cups even providing slightly better results. On the other hand, considering amplitudes, cVEPs and sVEPs provided fairly acceptable repeatability.
Epidermal cup electrodes can provide comparable results to those obtained with the "gold standard" epidural screws, while representing a simpler and less invasive technique to test nervous conduction along the visual pathways in the preclinical setting.
视觉诱发电位（VEP）是评估人类和动物模型中视觉通路神经传导的有力工具。传统上，硬膜外螺钉电极用于临床前研究中记录VEP。在此，我们通过使用无需外科手术的表皮杯状电极，测试了在临床前环境中用于临床VEP采集的相同非侵入性技术的可行性。
在七氟醚麻醉下，每周对14只黑色刺豚鼠进行一次双侧单眼闪光VEP记录，持续6周，其中7只植入硬膜外螺钉，7只使用直径6毫米的Ag/AgCl表皮杯状电极。
两种技术获得的VEP波形在形态上具有可比性。螺钉记录的VEP（sVEP）和杯状电极记录的VEP（cVEP）的主要视觉成分潜伏期无显著差异。表皮杯状电极记录的振幅值显著低于硬膜外螺钉记录的振幅值。两种技术提供的潜伏期和振幅随时间均稳定。此外，就潜伏期而言，两种方法随时间都能确保高度可重复的测量，表皮杯状电极甚至提供稍好的结果。另一方面，考虑振幅时，cVEP和sVEP的重复性相当可接受。
表皮杯状电极可提供与“金标准”硬膜外螺钉相当的结果，同时代表一种更简单、侵入性更小的技术，用于在临床前环境中测试视觉通路的神经传导。
