While nearly everyone experiences a headache on occasion, studies indicate that an estimated 45 million Americans suffer from chronic headaches annually. The World Health Organization estimates that one adult in 20 worldwide experiences a chronic headache condition. Various types of headaches, also called headache disorders, are among the most common disorders of the nervous system. They are pandemic and, in many cases, lifelong conditions. Many patients do not find relief through medication therapies and their headaches are classified as intractable. Chronic headaches very often negatively impact personal and family life, can lead to considerable medical costs, and may equate to decreased productivity in the workplace.

Researchers at the Feinberg School of Medicine, Northwestern University, analyzed the outcome of 32 patients undergoing cranial stimulation for intractable headaches. The results of this study, Cranial Peripheral Nerve Stimulation for Intractable Headache: Prospective Two Year Follow-Up Results, will be presented by Robert M. Levy, MD, PhD, at 3:57 to 4:08 p.m. on Wednesday, April 30, 2008, during the 76th Annual Meeting of the American Association of Neurological Surgeons in Chicago. The co-author is Janna L. Silverstein, BA.

Stimulation of the occipital nerve(s) has been reported to be effective in treating headaches and pain in the posterior head and neck when other treatment options have failed. However, many patients suffer from pain located outside of this area. “In this study, we prospectively evaluated the effect of chronic electrical stimulation of the peripheral nerves under the skin of the scalp or forehead to treat intractable headaches wherever patients experienced their pain,” stated Dr. Levy. In these patients, chronic stimulation was applied to the nerves in which sensory distribution paralleled the area of the patient’s headache pain. Thus, the nerves selected for stimulation depended on the location of the individual patient’s pain.

A total of 32 patients have been treated to date according to this protocol. Patients first underwent trial stimulation for a period of three to four days. Those who obtained greater than 50 percent pain relief during this trial were then implanted with a permanent system, which consisted of one to four leads (wires) and a pulse generator. Three of 32 patients (9 percent) failed to obtain sufficient relief and were not implanted permanently. In order to evaluate the long-term efficacy of chronic stimulation, patients were followed for a minimum of two years following treatment. Outcome data is available for 22 of these patients:

•Seventeen of 22 patients (77 percent) obtained good to excellent pain relief
•Three patients (14 percent) failed to obtain lasting pain relief and ultimately had the system removed.

Adjustments to the system were required in nine of 22 patients (41 percent) due to device malfunctions such as hardware failure and movement of the electrode. However, the rate of device failure has decreased with new surgical techniques and stronger device components. The other types of complications that arose included two episodes of electrode erosion through the skin (9 percent) and one (5 percent) infection related to this erosion.

“Overall results of our two-year study indicate that cranial peripheral nerve stimulation holds promise for treatment of intractable headaches in select patients who have tried other conservative treatment methods that have failed to provide relief,” concluded Dr. Levy.

Founded in 1931 as the Harvey Cushing Society, the American Association of Neurological Surgeons (AANS) is a scientific and educational association with more than 7,200 members worldwide. The AANS is dedicated to advancing the specialty of neurological surgery in order to provide the highest quality of neurosurgical care to the public. All active members of the AANS are certified by the American Board of Neurological Surgery, the Royal College of Physicians and Surgeons (Neurosurgery) of Canada or the Mexican Council of Neurological Surgery, AC. Neurological surgery is the medical specialty concerned with the prevention, diagnosis, treatment and rehabilitation of disorders that affect the entire nervous system, including the spinal column, spinal cord, brain and peripheral nerves.

Source: American Association of Neurological Surgeons (AANS)