Table 1.

Selected inclusion and exclusion criteria.

Selected inclusion criteria

1. Age from 18 to 65 years old.

2. Patient has been diagnosed with CCH according to the 2004 IHS criteria 3.1.2.

3. Patient reported a minimum of four CHs/week.

4. Patient reported dissatisfaction with current headache treatments.

5. Patient was able to distinguish cluster headaches from other headaches.

Selected exclusion criteria

1. Patient had a change in type or dosage of preventive headache medications within one month of enrollment.

2. Women of childbearing age who were pregnant, nursing, or not using contraception.

3. Patient had undergone facial surgery in the area of the pterygopalatine fossa or zygomaticomaxillary buttress ipsilateral to the planned implant site within the last four months.

4. Patient had been treated with radiation to the facial region within the last six months.

5. Patient had been diagnosed with any major infectious processes including osteomyelitis or primary or secondary malignancies of the face that were active or required treatment in the past six months.

6. Patient had undergone lesional radiofrequency ablation of the ipsilateral SPG, had undergone a block of the ipsilateral SPG, or had undergone botulinium toxin injections of the head and/or neck in the last three months.

7. Patient had another significant pain problem that might confound the study assessments in the opinion of the investigator.

CCH: chronic cluster headache; IHS: International Headache Society; SPG: sphenopalatine ganglion.