Neurostimulator Device segmentation by Type differentiates technologies by implant location and current pathway. Implantable systems—spinal-cord, deep-brain, sacral-nerve, gastric, and vagus-nerve stimulators—account for the dominant share because they deliver targeted, high-frequency pulses inside the body, securing higher ASP and recurring revenue from IPG replacements. External devices (TENS, TMS, CRFS) remain essential for acute pain and depression, but their market value is constrained by shorter replacement cycles and reimbursement limits. The implantable cluster therefore dictates overall market expansion, while external units provide volume access in price-sensitive geographies.