Peripheral neuromodulation and headaches: history, clinical approach, and considerations on underlying mechanisms

Abstract

Implantable peripheral neurostimulation was introduced in 1969 as a potential treatment for certain neuropathic pain syndromes, primarily involving the limbs. While a few early studies included implants for occipital neuralgia, serious interest in its potential as a treatment for head pain came only after our 1999 report of positive findings in a series of patients with occipital neuralgia. Subsequent investigators confirmed these initial findings, and then extended the application to patients with various primary headache disorders, including migraine. While most found a therapeutic response, the degree of that response varied significantly, and analysis suggests that the issue of paresthesia concordancy may be central, both in explaining the data, as well as providing direction for future endeavors. Therefore, while at present peripheral neurostimulation is gaining increasing acceptance as a treatment for chronic headaches, the precise clinical indications and procedures, as well as the underlying neurophysiological mechanisms, are still being worked out.

Fig. 1

Schematic depiction of a subcutaneously implanted combined occipital and supraorbital nerve stimulator. A standard implant is presented with the battery (IPG) located in the upper, outer gluteal region. a. From the IPG, four leads are passed subcutaneously such that two of the active terminal arrays are positioned over the greater occipital nerves. b. Two leads are passed over the ear to final subcutaneous positions of the terminal arrays over the supraorbital nerves. Standard strain-relief loops are depicted over the ear and at the IPG