Visual Prosthesis: Selling a Dream to Visually Impaired
(A literature review of advancements in the field of Visual Prosthesis)
Abstract
Visual prosthesis is by far the best bet to restore vision in a patient suffering with visual loss. This paper provides a literature review of the various technological advancements made over time and how these advancements have proved noteworthy in fields of visual prosthesis. To develop a basic understanding about the visual prosthesis, the anatomy and physiology of the eye is briefed along with types of prosthesis developed to restore vision in patients battling visual loss caused by deformity either in the structure of eye or in visual cortex. The goal was to chronologically review the progress made in …show more content…
And replacement of lost eye has been a matter of great gravity in the medical history, which has led to significant efforts in the direction of developing artificial eye to help the battling patients. It has been documented that Egyptians were the first one to wear artificial eye outside the socket as painted clay attached to the cloth.3 It was in sixteenth century that first in-socket artificial eyes were crafted out of gold and then later in glass by the Venetians. But it was not until World War II that acrylic plastic eyes came into account as German glass eyes became unavailable and plastic industry was at boom in the United States.4After around two decades, phosphenes were observed on electrical simulation of visual cortex via implanted electrodes.13A design was proposed in 1970 where the prosthesis could be worn with rechargeable batteries and circuits can be implanted in the cranium, connected with an array of electrodes inserted in the visual cortex. With this method a blind person was able to vie the flashes of images, when the electrical signals were translated to the visual cortex, though the bulkiness of the device was the major drawback.5 In 1977 Custom resin prosthetic were developed and painted with precision to replicate a normal gaze. This improved the esthetics of the prosthesis.6-7After a wait of approximately a decade study was made to introduce a bionic eye with dilating pupil. Prosthesis with two pupil diameters was developed and a magnet is used in order to adjust pupil diameter, on simulation by high and low intensities of light.8In 1991, Silicon chip with photodiodes as receptor was perfected, which could be invasively implanted between the layers of retina to enhance the sight.1 Autonomous motor system was shaped to detect the movement of the eye i.e. replace the eye by mechanical eye with the help of array of sensors, there by mimicking
(A literature review of advancements in the field of Visual Prosthesis)
Abstract
Visual prosthesis is by far the best bet to restore vision in a patient suffering with visual loss. This paper provides a literature review of the various technological advancements made over time and how these advancements have proved noteworthy in fields of visual prosthesis. To develop a basic understanding about the visual prosthesis, the anatomy and physiology of the eye is briefed along with types of prosthesis developed to restore vision in patients battling visual loss caused by deformity either in the structure of eye or in visual cortex. The goal was to chronologically review the progress made in …show more content…
And replacement of lost eye has been a matter of great gravity in the medical history, which has led to significant efforts in the direction of developing artificial eye to help the battling patients. It has been documented that Egyptians were the first one to wear artificial eye outside the socket as painted clay attached to the cloth.3 It was in sixteenth century that first in-socket artificial eyes were crafted out of gold and then later in glass by the Venetians. But it was not until World War II that acrylic plastic eyes came into account as German glass eyes became unavailable and plastic industry was at boom in the United States.4After around two decades, phosphenes were observed on electrical simulation of visual cortex via implanted electrodes.13A design was proposed in 1970 where the prosthesis could be worn with rechargeable batteries and circuits can be implanted in the cranium, connected with an array of electrodes inserted in the visual cortex. With this method a blind person was able to vie the flashes of images, when the electrical signals were translated to the visual cortex, though the bulkiness of the device was the major drawback.5 In 1977 Custom resin prosthetic were developed and painted with precision to replicate a normal gaze. This improved the esthetics of the prosthesis.6-7After a wait of approximately a decade study was made to introduce a bionic eye with dilating pupil. Prosthesis with two pupil diameters was developed and a magnet is used in order to adjust pupil diameter, on simulation by high and low intensities of light.8In 1991, Silicon chip with photodiodes as receptor was perfected, which could be invasively implanted between the layers of retina to enhance the sight.1 Autonomous motor system was shaped to detect the movement of the eye i.e. replace the eye by mechanical eye with the help of array of sensors, there by mimicking