The Perceptual Experience of Argus II Users
Retinitis Pigmentosa, Visual Impairment
About this trial
This is an interventional basic science trial for Retinitis Pigmentosa
Eligibility Criteria
Criteria for inclusion of Argus II users:
- Subject must be at least 25 years of age;
- Subject has been implanted with the Argus II system;
- Subject's eye has healed from surgery and the surgeon has cleared the subject for programming;
- Subject has the cognitive and communication ability to participate in the study (i.e., follow spoken directions, perform tests, and give feedback);
- Subject is willing to conduct psychophysics testing up to 4-6 hours per day of testing on 3-5 consecutive days;
- Subject is capable of understanding patient information materials and giving written informed consent;
- Subject is able to walk unassisted.
Criteria for inclusion of sighted control subjects:
- Subject speaks English;
- Subject must be at least 18 years of age;
- Subject has visual acuity of 20/40 or better (corrected);
- Subject has the cognitive and communication ability to participate in the study (i.e., follow spoken directions, perform tests, and give feedback);
- Subject is capable of understanding participant information materials and giving written informed consent.
- Subject is able to walk unassisted
Exclusion criteria:
- Argus II: Subject is unwilling or unable to travel to testing facility for at least 3 days of testing within a one-week timeframe;
- Sighted controls: Subject has a history of motion sickness or flicker vertigo
- All: Subject does not speak English;
- All: Subject has language or hearing impairment
Sites / Locations
- University of California, Santa Barbara
- Johns Hopkins University
- University of Michigan, Ann Arbor
- University of Minnesota
Arms of the Study
Arm 1
Experimental
Predicting the perceptual experience of retinal prosthesis patients
This intervention will assess the effect of different stimulation strategies on the perceptual experience of retinal prosthesis patients. We will produce visual percepts in patients either by directly stimulating electrodes (using FDA-approved pulse trains) or by asking them to view a computer or projector screen and using standard FDA-approved stimulation protocols (as is standardly used for their devices) to convert the computer or projector screen image into pulse trains on their electrodes. Existing blind users of the Argus II will be recruited for this study. Performance of Argus II users will be compared to performance of sighted subjects viewing a prosthetic vision simulation in virtual reality.