Study of a Suprachoroidal Retinal Prosthesis

Retinal visual prostheses are currently in early development as an intervention to improve functional vision in people who have become blind from retinal degenerative eye disease. This study follows on from an initial proof of concept study (n=3) between 2012 and 2014, and will test a second-generation retinal prosthesis device, which has the ability to be used outside of the laboratory environment (i.e. is fully implantable).

Inclusion criteria

• Aged 18 years or older
• Either gender
• A confirmed history of outer retinal degenerative disease such as retinitis pigmentosa or choroideremia
• Remaining visual acuity of bare light perception or less in both eyes
• Functional inner retina (ganglion cells and optic nerve), as shown by the ability to perceive light and/or a measurable corneal electrically evoked visual response
• A history of at least 10 years of useful form vision in the worse seeing eye

Exclusion criteria

• Optic nerve disease (history of glaucoma of More than 1 month, or history of any other optic neuropathy)
• Diseases of the inner retina including, but not limited to, central retinal artery or vein occlusion (CRAO, CRVO), end stage diabetic retinopathy, retinal detachment, traumatic retinal damage, infectious retinal disease, inflammatory retinal disease.
• Inability to visualise the retina due to corneal or other ocular media opacities (corneal degenerations, dense cataracts, trauma, lid malpositions)
• Any ocular condition that predisposes the participant to rubbing their eyes
• Cognitive deficiencies, including dementia or progressive neurological disease
• Psychiatric disorders, including depression, as diagnosed by a qualified psychologist
• Deafness or significant hearing loss
• Inability to speak or understand English
• Pregnancy
• Presence of a cochlear implant
• Participant enrolled in another investigational drug or device trial for the treatment of their ocular condition
• Poor general health, which would exclude them from obtaining a general anaesthetic
• Unrealistic expectations of the investigational device to provide functional vision
• Poorly controlled diabetes
• Epilepsy
• Unsuitable level of regular nystagmus (which would prevent ocular images from being obtained)
• Anyone with medical devices (implanted or carried) that could cause serious health problems if compromised by electro-magnetic interference