Biomedical Engineering Reference
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indicate that the TES activates the intrinsic retinal IGF-1 system and prevents
the death of the RGCs.
Our findings are consistent with the concept of electrical stimulation therapy,
which activates the intrinsic neuroprotective system. Electrical stimulation can
be applied to any nervous system non-invasively, repeatedly, and chronically
if an adequate system or devise is developed. TES is simple and non-invasive
therapy, and may have a therapeutic potential in other diseases of retinal neurons.
In fact, we reported that TES also prolonged the survival of photoreceptors and
delayed the loss of retinal function in RCS rats [28].
We also hypothesize that STS-based retinal implants for artificial vision can
work as a kind of neuroprotective device for various retinal dystrophic diseases
through electrical stimulation. This idea was supported by a recent report that
subretinal implants had a neuroprotective effect for photoreceptors of RCS rats,
although the neuroprotective contribution of electrical stimulation itself was
observed only in the ERG, not in the morphology [29]. In the future, the retinal
electrode may not only act as a retinal prosthesis but also may help to prevent
the degeneration of retinal cells.
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