This invention relates to an apparatus and method for making such apparatus
for providing controlled and directional stimulation patterns for tissue stimulation.
The apparatus may be useful in stimulation nervous tissue in the brain, about the
spinal cord, on nerve roots, about peripheral nerves, and in muscles, among others.
The apparatus includes a implantable pulse generator connected to a lead. The lead
has electrodes placed about a perimeter. In addition, the lead may include electrodes
placed longitudinally along the axis of the lead. By applying charge differences
between circumferentially distributed electrodes, a smaller stimulation field may
be established. In addition, by stimulating between electrodes distributed longitudinally
on the same side, a directional flow field may be established. Such leads are especially
useful in deep brain stimulation as the region in which a stimulation field is
strong enough to produce tissue stimulation is directional and minimized.