本期Nature Communications上發(fā)表的一項研究表明，移植了視網(wǎng)膜假體的大鼠對光有視覺反應,。當該假體被光刺激時，大鼠會在腦部負責視覺處理的區(qū)域誘發(fā)反應,。
近年來,，對有可能恢復盲人視力的光電池視覺假體的研究工作加快了步伐；與此同時,，雖然它們已被發(fā)現(xiàn)能夠刺激視網(wǎng)膜組織,，但它們是否能恢復視力卻沒有被評估過。Yossi Mandel及其同事向視網(wǎng)膜退化的大鼠植入視覺假體,，然后記錄來自其腦中視皮層的神經(jīng)反應,，將這種反應作為視力恢復程度的一個度量。他們發(fā)現(xiàn),，視皮層反應可響應于光刺激被誘發(fā),。這里所用的光刺激與早先研究中所用的刺激相似，后者研究的是這些裝置刺激視網(wǎng)膜組織的有效性,。作者承認,，還需要更多研究來確定這些裝置在恢復全部視力上到底有多成功，但他們希望,，這些研究將使人們對光電池方法用于視網(wǎng)膜假體的可行性更加有信心,。
“色素性視網(wǎng)膜炎”和與年齡相關(guān)的黃斑部退化是西方兩個最大的失明原因。雖然一些治療方法對某些個體能延緩這些疾病的病情發(fā)展,，但目前還沒有已知的治愈手段,。（生物谷Bioon.com）
生物谷推薦英文摘要：
Nature Communications DOI:10.1038/ncomms2980
Cortical responses elicited by photovoltaic subretinal prostheses exhibit similarities to visually evoked potentials
Yossi Mandel, Georges Goetz, Daniel Lavinsky, Philip Huie, Keith Mathieson, Lele Wang, Theodore Kamins, Ludwig Galambos, Richard Manivanh, James Harris & Daniel Palanker
We have previously developed a wireless photovoltaic retinal prosthesis, in which camera-captured images are projected onto the retina using pulsed near-IR light. Each pixel in the subretinal implant directly converts pulsed light into local electric current to stimulate the nearby inner retinal neurons. Here we report that implants having pixel sizes of 280, 140 and 70?μm implanted in the subretinal space in rats with normal and degenerate retina elicit robust cortical responses upon stimulation with pulsed near-IR light. Implant-induced eVEP has shorter latency than visible light-induced VEP, its amplitude increases with peak irradiance and pulse duration, and decreases with frequency in the range of 2–20?Hz, similar to the visible light response. Modular design of the arrays allows scalability to a large number of pixels, and combined with the ease of implantation, offers a promising approach to restoration of sight in patients blinded by retinal degenerative diseases.
