Argus retinal prosthesis, also known as a bionic eye, is an electronic

retinal implant Retinal prostheses for restoration of sight to patients blinded by retinal degeneration are being developed by a number of private companies and research institutions worldwide. The system is meant to partially restore useful vision to people who ...

manufactured by the

American American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, pe ...

company Second Sight Medical Products. It is used as a

visual prosthesis A visual prosthesis, often referred to as a bionic eye, is an experimental visual device intended to restore functional vision in those with partial or total blindness. Many devices have been developed, usually modeled on the cochlear implant or ...

to improve the vision of people with severe cases of

retinitis pigmentosa Retinitis pigmentosa (RP) is a genetic disorder of the eyes that causes loss of vision. Symptoms include trouble seeing at night and decreasing peripheral vision (side and upper or lower visual field). As peripheral vision worsens, people may ...

. The Argus II version of the system was approved for marketing in the

European Union The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe. The union has a total area of and an estimated total population of about 447million. The EU has often been des ...

in March 2011, and it received approval in the US in February 2013 under a humanitarian device exemption. The Argus II system costs about US$150,000, excluding the cost of the implantation surgery and training to learn to use the device. Second Sight had it’s IPO in 2014 and was listed on

Nasdaq The Nasdaq Stock Market () (National Association of Securities Dealers Automated Quotations Stock Market) is an American stock exchange based in New York City. It is the most active stock trading venue in the US by volume, and ranked second ...

. Production and development of the prosthesis was discontinued in 2020.

Medical use

The Argus II is specifically designed to treat people with

. The device was approved with data from a single-arm

clinical trial Clinical trials are prospective biomedical or behavioral research studies on human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel vaccines, drugs, dietar ...

that enrolled thirty people with severe retinitis pigmentosa; the longest follow-up on a trial subject was 38.3 months. People in the trial received the implant in only one eye and tests were conducted with the device switched on, or switched off as a control. With the device switched on, about 23% of the subjects had improvements in their ability to see; all had been at 2.9 or higher on the LogMAR scale and improvements ranged from just under 2.9 to 1.6 LogMAR – the equivalent of 20/1262 reading ability. 96% of the subjects were better able to identify a white square on a black computer screen; 57% were more able to determine the direction in which a white bar moved across a black computer screen. With the device switched on, about 60% were able to accurately walk to a door that was 20 feet away, as opposed to only 5% with the device switched off; 93% had no change in their perception of light.

Side effects

Among the thirty subjects in the clinical trial, there were nine serious adverse events recorded, including lower than normal

intraocular pressure Intraocular pressure (IOP) is the fluid pressure inside the eye. Tonometry is the method eye care professionals use to determine this. IOP is an important aspect in the evaluation of patients at risk of glaucoma. Most tonometers are calibrated to ...

, erosion of the

conjunctiva The conjunctiva is a thin mucous membrane that lines the inside of the eyelids and covers the sclera (the white of the eye). It is composed of non-keratinized, stratified squamous epithelium with goblet cells, stratified columnar epithelium ...

, reopening of the surgical wound, inflammation inside the eye, and retinal detachments. There is also a risk of bacterial infection from the implanted cables that connect the implant to the signal processor.

Surgical procedure

The implantation procedure takes several hours, with the person receiving the implant under

general anaesthesia General anaesthesia (UK) or general anesthesia (US) is a medically induced loss of consciousness that renders the patient unarousable even with painful stimuli. This effect is achieved by administering either intravenous or inhalational general ...

. The surgeon removes the vitreous humor and any membranes on the retina where the implant will be placed. The implant is attached to the surface of the retina with a tack. The cables connecting the implant to the processor are run through the

pars plana The ''pars plana'' (also known as ''orbicularis ciliaris'' ) (Latin: flat portion) is part of the ciliary body in the uvea (or vascular tunic), the middle layer of the three layers that comprise the eye. It is about 4 mm long, located near t ...

, a region near where the

iris Iris most often refers to: *Iris (anatomy), part of the eye *Iris (mythology), a Greek goddess * ''Iris'' (plant), a genus of flowering plants * Iris (color), an ambiguous color term Iris or IRIS may also refer to: Arts and media Fictional ent ...

and

sclera The sclera, also known as the white of the eye or, in older literature, as the tunica albuginea oculi, is the opaque, fibrous, protective, outer layer of the human eye containing mainly collagen and some crucial elastic fiber. In humans, and som ...

touch."IPG519: Interventional procedure overview of insertion of an epiretinal prosthesis for retinitis pigmentosa"

National Institute for Health and Care Excellence The National Institute for Health and Care Excellence (NICE) is an executive non-departmental public body of the Department of Health and Social Care in England that publishes guidelines in four areas: * the use of health technologies withi ...

Interventional Procedures Programme. Updated December 2014. Retrieved 4 September 2015.

Device

The Argus implant's primary external element is a

digital camera A digital camera is a camera that captures photographs in digital memory. Most cameras produced today are digital, largely replacing those that capture images on photographic film. Digital cameras are now widely incorporated into mobile device ...

mounted on eyeglass frames, which obtains images of the user's surroundings; signals from the camera are transmitted wirelessly to a computerised image processor. The processor is in turn connected by cables to the implant itself, which is surgically implanted on the surface of the person's retina and tacked into place. The implant consists of 60

electrode An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit (e.g. a semiconductor, an electrolyte, a vacuum or air). Electrodes are essential parts of batteries that can consist of a variety of materials de ...

s, each 200

micron The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...

s in diameter. The resolution of the 6 dot by 10 dot rectangular grid image (produced by the 6 by 10 array of 60 electrode, of which 55 are enabled ) in a persons vision is very low relative to normal visual acuity. This allows visual detection of edges of large areas of high contrast, such as door frames and sidewalks, to give the individual the capability to navigate in their environment more safely.

History

The implant's manufacturer, Second Sight Medical Products, was founded in

Sylmar Sylmar is a suburban neighborhood in the San Fernando Valley and is the northernmost neighborhood within the City of Los Angeles. Historically known for its profusion of sylvan olive orchards, Sylmar can trace its past to the 18th century and th ...

, California, in 1998, by Alfred Mann, Samuel Williams, and Gunnar Bjorg. Williams, an investor in a

cochlear implant A cochlear implant (CI) is a surgically implanted neuroprosthesis that provides a person who has moderate-to-profound sensorineural hearing loss with sound perception. With the help of therapy, cochlear implants may allow for improved speech und ...

company operated by Mann, approached Mann about founding a company to develop a similar product for the eye, and Mann called a meeting with the two of them and Robert Greenberg, who worked at Mann's foundation. Greenberg had previously worked on retinal prosthetics as a graduate student at

Johns Hopkins University Johns Hopkins University (Johns Hopkins, Hopkins, or JHU) is a private university, private research university in Baltimore, Maryland. Founded in 1876, Johns Hopkins is the oldest research university in the United States and in the western hem ...

, wrote the business plan, and was appointed as CEO of the new company when it was launched. Greenberg led the company as CEO through 2015 (and was chairman of the board through 2018). The first version of the prosthesis, the Argus I, was clinically tested on six people starting in 2002. The second version, the Argus II, was designed to be smaller and easier to implant, and was co-invented by Mark Humayun of the

USC Eye Institute The USC Gayle and Edward Roski Eye Institute, part of Keck School of Medicine of USC, is a center for ophthalmic care, research and education located in downtown Los Angeles, California. It has subsidiary clinics in Pasadena, Beverly Hills and A ...

, who had been involved in the clinical testing of the Argus I. The Argus II was first tested in

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

in 2006, and then a 30-person clinical trial was conducted in 10 medical centers across Europe and the United States.Duncan Graham-Rowe
"Visions of the future"
''

Wired UK ''Wired UK'' is a bimonthly magazine that reports on the effects of science and technology. It covers a broad range of topics including design, architecture, culture, the economy, politics and philosophy. Owned by Condé Nast Publications, it is ...

''. 6 August 2010. Retrieved 4 September 2015.Noel McKeegan
"Second Sight announces milestone in groundbreaking retinal implant trial"
Gizmag. 19 February 2008. Retrieved 4 September 2015.

Society and culture

Regulatory status

The Argus II received approval for commercial use in the European Union in March 2011. In February 2013, the FDA approved the Argus II under a humanitarian device exemption, authorizing its use for up to 4,000 people in the US per year.

Pricing and insurance

The Argus II was initially available at a limited number of clinics in

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical re ...

, the

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

, the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and North ...

and

Saudi Arabia Saudi Arabia, officially the Kingdom of Saudi Arabia (KSA), is a country in Western Asia. It covers the bulk of the Arabian Peninsula, and has a land area of about , making it the fifth-largest country in Asia, the second-largest in the A ...

, at an EU market price of US$115,000. When the Argus II launched in the United States in February 2013, Second Sight announced that it would be priced at around $150,000, excluding the cost of surgery and usage training. In August 2013, Second Sight announced that reimbursement payments had been approved for the Argus II for blind Medicare recipients in the United States.

Research

A trial in England funded by

NHS England NHS England, officially the NHS Commissioning Board, is an executive non-departmental public body of the Department of Health and Social Care. It oversees the budget, planning, delivery and day-to-day operation of the commissioning side of the ...

for ten patients began in 2017.

Aftermath

In 2020, Second Sight stopped providing technical support for the Argus, as well as for the successor device, Argus II, and for the brain implant, Orion; an investigation by ''

IEEE Spectrum ''IEEE Spectrum'' is a magazine edited by the Institute of Electrical and Electronics Engineers. The first issue of ''IEEE Spectrum'' was published in January 1964 as a successor to ''Electrical Engineering''. The magazine contains peer-revie ...

'' revealed that users risk – and in some cases, have already experienced – a return to blindness. Their Bionic Eyes Are Now Obsolete and Unsupported
by Eliza Strickland and Mark Harris, in ''

''; published 15 February 2022; retrieved 17 February 2022

References

{{reflist

External links

Second Sight official website
Bionics Biomedical engineering Neuroprosthetics Implants (medicine) Medical equipment Blindness American inventions 2011 introductions