Tissue damage by pulsed electrical stimulation

IEEE Trans Biomed Eng. 2007 Dec;54(12):2261-7. doi: 10.1109/tbme.2007.908310.

Abstract

Repeated pulsed electrical stimulation is used in a multitude of neural interfaces; damage resulting from such stimulation was studied as a function of pulse duration, electrode size, and number of pulses using a fluorescent assay on chick chorioallontoic membrane (CAM) in vivo and chick retina in vitro. Data from the chick model were verified by repeating some measurements on porcine retina in-vitro. The electrode size varied from 100 microm to 1 mm, pulse duration from 6 micros to 6 ms, and the number of pulses from 1 to 7500. The threshold current density for damage was independent of electrode size for diameters greater than 300 microm, and scaled as 1/r2 for electrodes smaller than 200 microm. Damage threshold decreased with the number of pulses, dropping by a factor of 14 on the CAM and 7 on the retina as the number of pulses increased from 1 to 50, and remained constant for a higher numbers of pulses. The damage threshold current density on large electrodes scaled with pulse duration as approximately 1/t0.5, characteristic of electroporation. The threshold current density for repeated exposure on the retina varied between 0.061 A/cm2 at 6 ms to 1.3 A/cm2 at 6 micros. The highest ratio of the damage threshold to the stimulation threshold in retinal ganglion cells occurred at pulse durations near chronaxie-around 1.3 ms.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Cell Membrane / pathology
  • Cell Membrane / radiation effects
  • Cells, Cultured
  • Chick Embryo
  • Chickens
  • Chorioallantoic Membrane / pathology
  • Chorioallantoic Membrane / physiopathology*
  • Chorioallantoic Membrane / radiation effects*
  • Dose-Response Relationship, Radiation
  • Electric Stimulation / adverse effects*
  • Eye Injuries / etiology
  • Eye Injuries / pathology
  • Eye Injuries / physiopathology
  • Radiation Dosage
  • Radiation Injuries / etiology*
  • Radiation Injuries / pathology
  • Radiation Injuries / physiopathology*
  • Retina / injuries*
  • Retina / physiopathology*