The sphenopalatine ganglion has sensory, motor, and autonomic components and is involved in the pathophysiology of cluster headache, the researchers explain. Percutaneous sphenopalatine ganglion radiofrequency ablation, they further point out, has been shown to improve episodic cluster headache but not chronic cluster headache.
Dr. Narouze and colleagues treated 15 patients with intractable chronic cluster headache with fluoroscopy-guided percutaneous radiofrequency ablation of the sphenopalatine ganglion via the infrazygomatic approach. All the patients had previously experienced temporary pain relief following sphenopalatine ganglion block.
Treatment, the team reports, led to significant improvement, compared to baseline, in the frequency and intensity of cluster headaches. The mean attack frequency fell from 17 attacks per week before treatment to 5.4 at the 1-month follow-up, and to 6.4, 7.8, 8.6, and 8.3, respectively, at the 3-, 6-, 12-, and 18-month follow up visits.
The mean attack intensity before treatment was 8.6 on a 0-10 scale, and 1-week post-treatment it was 3.2 (p < 0.0001). At 1-, 3-, 6-, 12-, and 18-month follow up visits, the mean attack intensity was 2.6, 3.2, 3.2, 3.4, and 4.2, respectively.
Sphenopalatine ganglion radiofrequency ablation also led to significant improvement in the pain disability index — it improved from 55 at baseline to 17.2 and 25.6 at 6 and 12 months, respectively, (p < 0.001).
According to the investigators, 7 of the 15 patients reported temporary paresthesias in the upper gums and cheek that lasted for 3 to 6 weeks and then resolved completely.
One patient reported a persistent coin-like area of permanent anesthesia over his cheek. “However, he was very satisfied with the treatment as his headache completed resolved,” the investigators report.
“Two patients reported complete relief of their usual unilateral headache symptoms and instead they developed episodic cluster headache on the contralateral side,” according to Dr. Narouze and colleagues.
“Precise needle placement with the use of real-time fluoroscopy and electrical stimulation prior to attempting radiofrequency lesioning may reduce the incidence of adverse events,” they conclude.