In this thesis, we investigate and develop three flexible microelectronic technologies for managing glaucoma, slowing down neural degeneration and improving the delivery of bionic vision using visual prosthetic technologies. The first device focuses on monitoring intraocular pressure as a risk factor that is commonly known to induce blindness in glaucoma patients. The second device is designed and built to further facilitate the investigation of the hypothesis whether stimulating visual cortex with light slows down the degeneration of optic nerve pathways in the visual circuitry in the brains of animals and eventually be able to optimize the parameters and maximize the positive effects shown in earlier studies. The third project reports a successful attempt in improving a currently existing visual prosthetic implantable device made by a company called Second Sight Medical Products Inc. For the first project, we create a contact lens that incorporates a pressure sensor and sends out continuous data on the pressure of the eyes to external devices through a pair of goggles that communicates with the lens on the surface of the patient’s eye. The second part of the thesis focuses on the development of a device that helps with investigating the effect of optogenetic stimulation on slowing down the degenerative processes in neural pathways that lead to loss of retinal cells and eventually blindness. Thirdly, we develop a new coating technology for the currently existing microelectrodes that some versions of them are currently commercially available for the delivery of bionic vision directly through a flexible microelectrode array implanted on the visual cortex of humans. These three technologies described, developed and advanced in this thesis allow a multi-factorial approach to preventing vision loss and managing blindness caused by multitude of reasons including but not limited to glaucoma, macular degeneration, and retinitis pigmentosa. While the wearable contact lens can help monitoring the pressure in the eye round-the-clock, the cortical prosthetic devices using either light or electricity stimulate the visual cortex that can either slow down vision loss or reintroduce a new sensory domain called bionic vision for blind patients. We demonstrate proof of concept for the wearable pressure sensing contact lens by demonstrating the responsivity in ex vivo experiments on enucleated animal eyes and the eyes intact in post-mortem dog and rabbit heads. Next we show proof of concept for a wireless and miniaturized optogenetic stimulator device designed for experiments on mice. These micro-controlled light delivery systems are compact and low-cost allowing future experiments in vivo that can further demonstrate the efficacy of light delivery in battling and slowing down or perhaps stop vison loss caused by various degenerative and progressive neural diseases. Last but not the least, we advance a commercially existing visual prosthetic system and develop and incorporate new coating material for its electrical stimulation electrodes so that it can better deliver bionic vision to those patients who have already lost their vision.
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