Electrotherapeutic device/protocol design considerations for visual disease applications

One of the more interesting applications of electrotherapy involves its use in the treatment of visual disease; including retinitis pigmentosa, diabetic retinopathy and macular degeneration. The therapeutic efficacy of electrotherapy is highly dependent upon the incorporation of appropriate design choices for both the electrotherapeutic device and treatment protocol. Electrotherapeutic design drivers include electrode probe-tissue interface, device reliability, operational constraints, treatment protocol procedures, and safety. In FDA guided and FDA supervised clinical studies (FDA pre-IDE numbers 1980275 and 1000038 and FDA IDE number G020106) involving electrotherapeutic intervention for dry macular degeneration, 61% of a 400 patient cohort treated with electrotherapy achieved visual acuity improvements of two lines or more on the Snellen chart. Average electric current intensities in the range of 60 to 125 muA were utilized to achieve this level of therapeutic efficacy. With further improvements in the design of electrotherapeutic device waveforms, frequency selection, treatment protocols and electrode probe configurations; long-term visual acuity improvements of two lines or better on the Snellen chart can be anticipated for more than 60% of the patients who are in the early stages of retinitis pigmentosa, diabetic retinopathy and dry macular degeneration.