Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611-3008, USA.
Hear Res. 2010 Oct 1;269(1-2):102-11. doi: 10.1016/j.heares.2010.06.021. Epub 2010 Jul 13.
Previous research has shown that neural stimulation with infrared radiation (IR) is spatially selective and illustrated the potential of IR in stimulating auditory neurons. The present work demonstrates the application of a miniaturized pulsed IR stimulator for chronic implantation in cats, quantifies its efficacy, and short-term safety in stimulating auditory neurons. IR stimulation of the neurons was achieved using an optical fiber inserted through a cochleostomy drilled in the basal turn of the cat cochlea and was characterized by measuring compound action potentials (CAPs). Neurons were stimulated with IR at various pulse durations, radiant exposures, and pulse repetition rates. Pulse durations as short as 50 mus were successful in evoking CAPs in normal as well as deafened cochleae. Continual stimulation was provided at 200 pulses per second, at 200 mW per pulse, and 100 mus pulse duration. Stable CAP amplitudes were observed for up to 10 h of continual IR stimulation. Combined with histological data, the results suggest that pulsed IR stimulation does not lead to detectable acute tissue damage and validate the stimulation parameters that can be used in future chronic implants based on pulsed IR.
先前的研究表明，红外辐射（IR）的神经刺激具有空间选择性，并说明了 IR 在刺激听觉神经元方面的潜力。本工作展示了一种微型脉冲 IR 刺激器在猫慢性植入中的应用，对其刺激听觉神经元的功效和短期安全性进行了量化。通过在猫耳蜗底部的鼓室切开术中插入光纤来实现对神经元的 IR 刺激，并通过测量复合动作电位（CAP）来对其进行表征。使用各种脉冲持续时间、辐射暴露和脉冲重复率的 IR 对神经元进行刺激。在正常和耳聋的耳蜗中，短至 50 μs 的脉冲持续时间就能成功地引发 CAP。以每秒 200 个脉冲、每个脉冲 200 mW 和 100 μs 脉冲持续时间持续刺激。在长达 10 小时的连续 IR 刺激下，观察到稳定的 CAP 幅度。结合组织学数据，结果表明，脉冲 IR 刺激不会导致可检测的急性组织损伤，并验证了可用于基于脉冲 IR 的未来慢性植入物的刺激参数。
