The SPG is a unique final common pathway ganglion that may be involved in migraine and cluster headache, told Dr. Stewart J. Tepper from Cleveland Clinic in Ohio. Intermittently or chronically interrupting its outflow offers an approach to acute and possibly preventive approaches to intractable migraine.

Based on this knowledge and on anecdotal reports claiming termination of migraine by blockade of the SPG, Dr. Tepper and team analyzed that stimulation of the SPG might interfere with parasympathetic postganglionic outflow which results in termination of migraine.

Total 11 patients with a history of migraine headaches were tested with this approach, including 9 patients with medication overuse headache and 2 with refractory episodic migraine.

Of all, 2 patients experienced complete abolition of induced migraine headaches within 3 minutes of SPG stimulation. More over, patient did not show a response to sham stimulation.

The authors reported that 3 patients had reduced pain with SPG stimulation, 5 had no response to SPG stimulation, and 1 patient was not stimulated.

The study found that all 5 patients who showed no response to SPG stimulation had medication overuse headache, and all had poor anatomic placement of the electrode, poor physiological sensory response to stimulation for localization, or both.

There were no incidence of adverse events, and headaches returned with their usual regularity following study participation.

This study suggests a possible role for SPG stimulation in the treatment of medically refractory migraine headaches, the investigators conclude.

We also want to try SPG stimulation for episodic migraine, but we still have a few regulatory hurdles to cross, Dr. Tepper said. We hope to be able to do that study within the next 6 months.

Our long-term goal is to develop an alternative approach that allows minimally invasive instrumentation that provides chronic SPG stimulation without requiring repeated electrode insertions, Dr. Tepper said.