Artificial Human vision - KSOS

428 Kerala Journal of Ophthalmology Vol. XXI, No. 4
stimulator based on multiple microchips have been tried
on animal experiments, another Japanese project based
on supra choroidal –trans retinal stimulation, the
minimal invasive retinal project of Prof Heinrich
Gerding in Switzerland, the Seoul Artificial project of
Prof Hum Chung etc.
Conclusion
With ongoing advances in technology, surgical
techniques and treatment options, there has been
significant advancement towards restoring some vision
to patients suffering from RP.
Although many advances have been made, the field of
artificial vision is still young.We hope within another
five years, patients with retinitis pigmentosa will be
able to receive a retinal prosthesis, suitable to their
needs, and possess vision allowing them to possibly
perform. The management options of AMD has changed
a lot since the retinal prosthesis started developing in
nineties. In the dawn of anti VEGF era, the number of
patients who needs prosthetic vision due to this disease
is expected to fall according to many researchers.
Future research by all AHV groups will need to address
more on the energy needs, its supply, long-term
biocompatibility of microelectronics in the saline
environment of the eye in terms of hermetic packaging
of the micro fabricated electrode arrays, minimization
of the heat generated and dissipated with its use, effect
of chronic electrical stimulation on the retina etc. In
addition to this, significant attention needs to be given
to the manner in which visual images will be encoded
and delivered in patterns of electrical stimulation to
the retina. Plasticity of the visual system in response to
electrical stimulation as well as how the brain interprets
a pattern of stimulation resulting from thousands of,
electrodes has to be understood well and will be crucial
in the evolution of better prosthetic design.
We can thus tell our patients with outer retinal
degenerations that there is progress toward an
electronic retinal prosthesis but fully functional, longlasting
devices are not on the immediate horizon.
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