Subcutaneous Depth Electrodes (SDE)

Our Subcutaneous Depth Electrodes (SDE) are accessories to our Subcutaneous Transmitters (SCTs), Implantable Stimulator-Transponders (ISTs), and Electrode Interface Fixtures (EIF). They attach to the end of an electrode or stimulation lead by means of a pin and socket, a crimp connection, or a solder joint. Depth electrodes allow us to measure biopotentials and deliver stimuli to deeper parts of the brain.

The R-Electrode provides a guide cannula with an adjacent, teflon-insulated stainless steel wire. The cannula allows us place a syringe tip at the same depth as the wire end. Accompanying the R-Electrode is a dummy cannula cap that stops water and debris entering the guide. The J-Electrode provides a plastic pedestal to clamp onto during surgery. We bury its socket in cement, cut the wire above the pedestal, pull off the pedestal, trim the wire, and cover once more to produce a low-profile depth electrode connection with the absolute minimum of cutting force during surgery. The W-Electrode provides a tube for clamping and a socket contact. The tube is thinned above the socket, allowing us to cut the tube with relative ease, although more force is required than to cut the wire above a J-Electrode. The X-Electrode accepts a crimp contact, which we must squeeze with forceps before applying cement and cutting the tube. The X-Electrode is more difficult to deploy, but it avoids solder joints, and so produces the quietest low-frequency signal.