Biomedical Engineering Reference
In-Depth Information
biocompatible material. However, these are very preliminary results. Further
studies need to be carried out to implant the micro-camera into a cat's eye to
evaluate the long-term biocompatibility and imaging function.
Conclusion
A type of visual prosthesis with stimulating electrode penetrating into optic nerve
is introduced in this chapter. The feasibility of this visual prosthesis has been
validated using some animal experiments. Many more animal experiments will
be carried out to find out the rules of visual perception elicited by electrical stimu-
lation in our project. To some degree, the hardware design of visual prosthesis
depends much on the development of MOEMS technology. But a number of
effective image-processing strategies can be explored and evaluated to enhance
the performance of visual prosthesis and even decrease the difficulty of complex
hardware design. In this chapter, we presented some tests of image-processing
strategies by computer simulation and DSP implementation in real time. A high
precision neural stimulator is also under study. An implantable CMOS micro-
camera with special design is also evaluated. Although much more tests for its
long-term biocompatibility must be carried out, the preliminary results showed
that the micro-camera was suitable for our visual prosthesis with minimal loss
of image quality in the simulation physiological circumstance.
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