Argus Retinal Prosthesis

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The Argus Retinal Prosthesis is an electronic retinal implant produced by the California-based company Second Sight.[1] It is designed primarily to improve the vision of those with severe cases of the inherited disease retinitis pigmentosa. In March 2011, the Argus II version of the system was approved for clinical and commercial use in the European Union.[2] In February 2013, the Argus II became the first commercial visual prosthesis to be approved for use in the United States.[3][4]

The system can only provide a modest improvement in vision – with the best clinically proven outcome being a visual acuity of 20/1260 – and most users experience some degree of adverse side effects, with these reportedly being severe in 36%.[5]

Contents

Effects[edit]

By June 2012, the second generation of the Argus system had been implanted into a total of 32 people.[6] The best result achieved by the device was a visual acuity of 20/1260,[6] where blindness is defined as greater than 20/500 by the World Health Organization, and as 20/200 in the United States. Thus, while vision has been improved, no cases of actual blindness have been resolved by the device. With respect to safety, serious adverse effects occurred in eleven out of 30 users, minor adverse effects occur in 17 out of 30 users, and no adverse effects were found in only two out of 30 people. One user had their Argus device removed due to severe adverse effects.[5]

Design[edit]

The Argus II is primarily designed to treat sufferers of retinitis pigmentosa, a genetic ocular disease which affects approximately 1.5 million people worldwide.[7] The device consists of two primary elements – a retinal implant and an eyeglass-mounted camera. The camera records real-time images, which are sent wirelessly to the implant by a built-in video processor.[8] The implant then uses 60 electrodes to stimulate the patient's remaining healthy retinal cells and send visual information to the optic nerve, thus restoring the ability to discern light and movement.[9] In some cases, the Argus II can restore sufficient vision to allow blind users to read large print books.[2] The Argus II currently has a unit cost of around US$100,000.[4]

Regulation status[edit]

The Argus II received approval for clinical and commercial use in the EU in March 2011.[2] It was initially available at a limited number of clinics in France and Switzerland, and had an EU market price of $115,000.[2] Thereafter, Second Sight began seeking US clinical approval for the device. In October 2012, advisers to the US Food and Drug Administration (FDA) voted unanimously to approve the Argus II.[4] In February 2013, the FDA approved the Argus II as a "humanitarian use device", authorizing its use for up to 4,000 US patients per year.[4]

History[edit]

The implant's developer, Second Sight, was founded in Sylmar, California, in 1998,[1] although low-level research and design efforts began in 1991.[10] The first version of the prosthesis, the Argus I, was developed in 2002, and clinically tested on six patients.[1] The second version, the Argus II, was first tested in Mexico in 2006, whereafter a 30-patient clinical trial was conducted in ten medical centers across Europe and the United States.[1]

See also[edit]

References[edit]

  1. ^ a b c d "History". Second Sight. Retrieved 17 February 2013. 
  2. ^ a b c d "A Bionic Eye Comes to Market". MIT Technology Review. 7 March 2011. Retrieved 17 February 2013. 
  3. ^ "The blind may soon see again as science prepares to market high-tech cyborg eye". Daily Mail. 9 February 2013. Retrieved 12 February 2013. 
  4. ^ a b c d "FDA approves first retinal implant for rare eye disease". Reuters. 14 February 2013. Retrieved 14 February 2013. 
  5. ^ a b "The HDE Summary of Safety and Probable Benefit: What It Is and Does" (PDF). FDA. 2013. Retrieved 5 April 2013. 
  6. ^ a b Fernandes, RA; Diniz, B; Ribeiro, R; Humayun, M (25 June 2012). "Artificial vision through neuronal stimulation". Neuroscience Letters 519 (2): 122–8. PMID 22342306. 
  7. ^ "Retinitis pigmentosa – Prevalence". Institut de la Vision. Updated 9 February 2012. Retrieved 17 February 2013. 
  8. ^ "FDA clears Argus II 'bionic eye' for sale in the US (video)". Engadget. 15 February 2013. Retrieved 17 February 2013. 
  9. ^ "Argus IITM Retinal Prosthesis System for peripheral retinal degeneration" (PDF). NHSC. June 2011. Retrieved 17 February 2013. 
  10. ^ "World's first bionic eye approved by FDA, aims to treat blindness". Russia Today. 16 February 2013. Retrieved 18 February 2013. 

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