Miniature implantable device and methods

An implantation system, comprising:

• a stylet comprising an elongate member and a first mating feature at a distal end of the elongate member;
• and
• an implantable device configured to receive a wireless signal and to generate one or more electrical pulses from the wireless signal for exciting a tissue, the implantable device comprising:
• a cylindrical body defining a longitudinal axis of the implantable device,
• a plurality of electrodes distributed along the cylindrical body and configured to deliver the one or more electrical pulses,
• an anchoring feature adjacent the cylindrical body and disposed proximal to the plurality of electrodes for securing the implantable device to the tissue, and
• a second mating feature disposed proximal to the anchoring feature, disposed in-line with the longitudinal axis of the implantable device, and defining a proximal end of the implantable device, the second mating feature configured to mate with the first mating feature such that the stylet and the implantable device can be delivered percutaneously to a body of a subject together as an assembly;
• wherein the assembly of the stylet and the implantable device is sized and shaped to be passed through a lumen of an introducer needle that is of gauge 18 or smaller and further through a percutaneous incision site on the body, and
• wherein the stylet is sufficiently rigid such that the assembly of the stylet and the implantable device can be passed through the lumen of the introducer needle and further through the percutaneous incision site on the body.