Kelly Shawn K, Shire Douglas B, Chen Jinghua, Doyle Patrick, Gingerich Marcus D, Drohan William A, Theogarajan Luke S, Cogan Stuart F, Wyatt John L, Rizzo Joseph F
VA Boston Healthcare System (VABHS) and the Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA.
Annu Int Conf IEEE Eng Med Biol Soc. 2009;2009:200-3. doi: 10.1109/IEMBS.2009.5333619.
A miniaturized, hermetically-encased, wirelessly-operated retinal prosthesis has been developed for implantation and pre-clinical studies in Yucatan mini-pig animal models. The prosthesis conforms to the eye and drives a microfabricated polyimide stimulating electrode array with sputtered iridium oxide electrodes. This array is implanted in the subretinal space using a specially-designed ab externo surgical technique that affixes the bulk of the prosthesis to the surface of the sclera. The implanted device includes a hermetic titanium case containing a 15-channel stimulator chip and discrete power supply components. Feedthroughs from the case connect to secondary power- and data-receiving coils. In addition, long-term in vitro pulse testing was performed on the electrodes to ensure their stability for the long lifetime of the hermetic case. The final assembly was tested in vitro to verify wireless operation of the system in biological saline using a custom RF transmitter circuit and primary coils. Stimulation pulse strength, duration and frequency were programmed wirelessly using a custom graphical user interface. Operation of the retinal implant has been verified in vivo in one pig for more than three months by measuring stimulus artifacts on the eye surface using a contact lens electrode.
一种小型化、气密封装、无线操作的视网膜假体已被开发出来，用于在尤卡坦小型猪动物模型中进行植入和临床前研究。该假体贴合眼睛，并驱动带有溅射氧化铱电极的微加工聚酰亚胺刺激电极阵列。使用专门设计的外路手术技术将该阵列植入视网膜下间隙，该技术将假体的大部分固定在巩膜表面。植入装置包括一个气密钛壳，其中包含一个15通道刺激器芯片和分立电源组件。从外壳引出的馈通线连接到二次电源和数据接收线圈。此外，对电极进行了长期体外脉冲测试，以确保其在气密外壳的长寿命期间的稳定性。最终组件在体外进行了测试，以使用定制射频发射器电路和初级线圈验证系统在生理盐水中的无线操作。使用定制图形用户界面无线编程刺激脉冲强度、持续时间和频率。通过使用隐形眼镜电极测量眼表面的刺激伪迹，已在一只猪体内验证视网膜植入物的操作超过三个月。
