Abstract
Purpose:
The Food and Drug Administration (FDA) recently approved the Argus II Retinal Prosthesis System for use among patients with late stage Retinitis Pigmentosa (RP). While RP is a relatively rare disease, its degree of visual impairment is variable and not every patient with RP is a good candidate for the Argus II device. Furthermore, there appears to be a high degree of variability in patient acceptance of the device after it is implanted. The FDA has issued basic guidelines outlining which patients should receive this device, but these are broad and general. Here we share our experiences evaluating 16 patients for the Argus II device along with corresponding patient characteristics data that in the future could serve as prognostic factors for device efficacy and patient acceptance. This review of our evaluation process, which is based on current FDA guidelines, aims to identify an improved method for deployment of the Argus II device.
Methods:
We screened 16 patients at the USC Eye Institute for the Argus II device, 11 (69%) of whom qualified for the device and 5 (31%) of whom did not. Screening involved a standardized survey, verbal assessment, and complete eye exam. Patient data was collected in a retrospective manner from the patients’ medical records.
Results:
Patient characteristics data include the current age (37 to 90 years, median 74), age at diagnosis of RP (10 to 69 years, median 38), visual acuity (20/70 to NLP), and family history of RP (8 had while 7 had none). Among the patients who did not qualify for surgery, the majority were due to difficulty attending regular post-operative follow-up appointments. As eligible patients are implanted with the Argus II device are tracked longitudinally, we expect that correlations will emerge between these characteristics data and the data describing functional outcomes.
Conclusions:
Patients currently screened for the Argus II device represent a diverse group with a broad range of ages, disease durations, visual acuities, and other clinical characteristics. Some of these characteristics will likely play a vital role in determining device efficacy and patient acceptance once the prosthesis is implanted. This study represents the first step toward developing a formal evaluation process to determine the best candidates for the Argus II implant as it becomes more widely available to patients across the country.