OBJECTIVE: Electrical neurostimulation has traditionally been limited to the use of charge-balanced waveforms. Charge-imbalanced and monophasic waveforms are not used to deliver clinical therapy, because it is believed that these stimulation paradigms may generate noxious electrochemical species that cause tissue damage. APPROACH: In this study, we investigated the dissolution of platinum as one of such irreversible reactions over a range of charge densities up to 160 μC cm-2 with current-controlled first phase, capacitive discharge second phase waveforms of both cathodic-first and anodic-first polarity. We monitored the concentration of platinum in solution under different stimulation delivery conditions including charge-balanced, charge-imbalanced, and monophasic pulses. MAIN RESULTS: We observed that platinum dissolution decreased during charge-imbalanced and monophasic stimulation when compared to charge-balanced waveforms. SIGNIFICANCE: This observation provides an opportunity to re-evaluate the charge-balanced waveform as the primary option for sustainable neural stimulation.
OBJECTIVE: Electrical neurostimulation has traditionally been limited to the use of charge-balanced waveforms. Charge-imbalanced and monophasic waveforms are not used to deliver clinical therapy, because it is believed that these stimulation paradigms may generate noxious electrochemical species that cause tissue damage. APPROACH: In this study, we investigated the dissolution of platinum as one of such irreversible reactions over a range of charge densities up to 160 μC cm-2 with current-controlled first phase, capacitive discharge second phase waveforms of both cathodic-first and anodic-first polarity. We monitored the concentration of platinum in solution under different stimulation delivery conditions including charge-balanced, charge-imbalanced, and monophasic pulses. MAIN RESULTS: We observed that platinum dissolution decreased during charge-imbalanced and monophasic stimulation when compared to charge-balanced waveforms. SIGNIFICANCE: This observation provides an opportunity to re-evaluate the charge-balanced waveform as the primary option for sustainable neural stimulation.
Authors: Adolfo Ramirez-Zamora; James J Giordano; Aysegul Gunduz; Peter Brown; Justin C Sanchez; Kelly D Foote; Leonardo Almeida; Philip A Starr; Helen M Bronte-Stewart; Wei Hu; Cameron McIntyre; Wayne Goodman; Doe Kumsa; Warren M Grill; Harrison C Walker; Matthew D Johnson; Jerrold L Vitek; David Greene; Daniel S Rizzuto; Dong Song; Theodore W Berger; Robert E Hampson; Sam A Deadwyler; Leigh R Hochberg; Nicholas D Schiff; Paul Stypulkowski; Greg Worrell; Vineet Tiruvadi; Helen S Mayberg; Joohi Jimenez-Shahed; Pranav Nanda; Sameer A Sheth; Robert E Gross; Scott F Lempka; Luming Li; Wissam Deeb; Michael S Okun Journal: Front Neurosci Date: 2018-01-24 Impact factor: 4.677