feasibility study of compensation for blindness with the prima system in patients with dry age related macular degeneration

Conditions: Dry Age-related Macular Degeneration

Summary: in this study, the principle functionality of the device will be tested in humans for the first time. the study will evaluate the extent to which patients with atrophic dry age related macular degeneration (amd) have evoked light perception using the implant.

in this study subjects are provided with a prima sub-retinal implant in one eye. a camera integrated in the external components of the implant captures visual information of the environment, this information is processed by a pocket processor and then transmitted via projected ir light onto the implant. the implant received the projected ir light and stimulates the nerve cells of the retina. interim analysis will be performed at 6 months after implantation.

Eligibility criteria:
inclusion criteria: * is 60 years or older at the date of enrolment; * has a confirmed diagnosis of advanced dry age related macular degeneration with an atrophy size of at least 3 optic disc diameters; * has best corrected visual acuity of the study eye of logmar 1.3 (20/400) or worse measured by etdrs; * has no foveal perception measured by micro-perimetry in the study eye (≤ 4 db on opko scale or equivalent) ; * has a study eye that is able to perceive light; * has useful vision on the non-study eye; * has a refraction of study eye between -3 and + 4 (limits included) for patient with iol (there is no refraction criteria for patients with natural lens); * understands and accepts the obligation to present for all schedule follow-up visits. * patient signed informed consent exclusion criteria: * has cataracts that may influence the visual function of the study eye; * has an aphakic study eye * had cataract surgery in the last 1 month; * active sub-macular choroidal neovascularization in the study eye; * has any disease (other than study allowed diseases) or condition that affects retinal function of the study eye (e.g., central retinal artery/vein occlusion, end-stage diabetic retinopathy, retinal detachment, infectious or inflammatory retinal disease, severe glaucoma, optic neuropathy, myopic chorio-retinal atrophy etc.); * has an implanted telescope in one eye; * has any disease or condition that prevents adequate examination of the study eye including, but not limited to, corneal degeneration that cannot be resolved prior to implantation. note, that this criterion is also important for the function of the implant; * has an endothelia cell count of less than 1000 cells/mm² in the study eye; * suffers from nystagmus; * has any disease or condition that precludes the understanding or communication of the informed consent, study requirements or test protocols (e.g., deafness, severe multiple sclerosis, amyotrophic lateral sclerosis, severe neuritis, etc); * has a history of epileptic seizure; * has a history of chronic or recurrent infection or inflammation that would preclude participation in the study; * has a known sensitivity to the contact materials of the implant (iridium oxide, silicon-carbide and titanium); * presents with hypotony in the study eye; * presents with hypertony in the study eye; * has another active implanted device (e.g. cochlear implant, pacemaker) that may interfere with the device function, or diagnoses requiring such an active implant; * has active cancer or a history of intraocular, optic nerve or brain cancer and metastasis; * is an immune-suppressed subject (e.g., due to hiv positive diagnosis, etc.); * is carrier of multi-resistant germs; * is receiving anticoagulation therapy that cannot be adapted to allow eye surgery; * is participating in another investigational drug or device study that may interfere with the present study; * patients with recurrent or chronic inflammations or infections are excluded from the study. specifically, patients with the following disorders are excluded: * common inflammation - severe chronic and consuming diseases that frequently associated with infection (e.g. crohn disease, whipple's disease); * active inflammation in the area of the eye (e.g. herpes of cornea and/or conjunctiva, recurrent blepharoconjunctivitis, hordeolum, chalazion); * has a severe psychological disorder. when in any doubt, an expert assessment needs to be arranged to clarify whether the patient's psychological health is suitable for the trial. in any doubts of the subjects psychological status a clinical psychologist, psychologist or the community doctor/general practitioner should be involved. the patient must have the legal capacity to sign the informed consent; * has severe renal, cardiac, hepatic etc. organ diseases; * has head dimension that are incompatible with the visual interface. * has too high and unrealistic expectation (e.g., believes that a benefit is guaranteed or expect normal vision after surgery)

Keywords: atrophic macular degeneration geographic atrophy macular degeneration dry macular degeneration amd retina implant retinal prosthesis visual prosthesis