The Argus II Retinal Implant is a revolutionary new device, which offers vision to patients who are blind from retinal degeneration - retinitis pigmentosa. These patients have no alternatives. Patients typically can achieve ambulatory vision.

This study is an investigator-sponsored, observational, controlled, prospective, single-center study. The purpose of this current study is how it affects people's visual function and activities of daily living and to collect additional data on Argus II users in order to monitor the System's safety. In addition, data about the long-term reliability of the System will be gathered.

The Argus II retinal implant will be surgical implanted into patients who are blind but the surgical procedure is not a part of this observational study. Our hypothesis is that the visual results in our hands will be comparable to those reported in the FDA study. We will use the results of this study to plan future enhancements to the service and to explore the use of the device for other blinding conditions.

Inclusion Criteria:

•Adults, age 25 years or older with severe to profound outer retinal degeneration.

but some residual light perception. If no residual light perception remains, the retina must be able to respond to electrical stimulation and previous history of useful form vision.

Exclusion Criteria:

• Ocular diseases or conditions that could prevent the Argus II System from working (e.g. optic nerve disease, central retinal artery or vein occlusion, history of retinal detachment, trauma, severe strabismus).
• Ocular structures or conditions that could prevent the successful implantation of the Argus II Implant or adequate healing from surgery (e.g. extremely thin conjunctiva, axial length <20.5 mm or > 26 mm, corneal ulcers, choroidal neovascularisation in the area of the intended tack location, etc.).
• Ocular diseases or conditions (other than cataracts) that prevent adequate visualisation of the inner structures of the eye (e.g. corneal opacity, etc.).
• Inability to tolerate general anaesthesia or the recommended antibiotic and steroid regimen associated with the implantation surgery.
• Predisposition to eye rubbing.

Patients with severe to profound outer retinal degeneration