High-volume anesthetic suboccipital nerve blocks show potential as a treatment option for patients suffering from refractory chronic cluster headaches, according to an observational case series study published in Headache.
For this retrospective 7-year study, researchers followed 10 patients (9 men and 1 woman) who were refractory to treatment for their chronic cluster headaches. Over this time period, the patients were injected at least twice with a solution of 9 mL of 1% lidocaine and 1 mL of triamcinolone 40 mg at the suboccipital fossa. Complete response to treatments was defined as no cluster headaches, and a partial response was defined as either fewer attacks, lower intensity attacks, or shorter lasting attacks.
A complete response occurred in 9 patients, with their relief occurring in less than 24 hours. One patient did not show any response. For responders, the mean response duration was 10.3 weeks (mean range=1.5 to 31 weeks), with 2 patients having pain relief for 44 weeks. Patient’s response time was very consistent after each injection, only varying up to 7 days. Serial injections improved quality of life for many patients. The woman in the study had a long remission time, and over the course of the study, her headaches transitioned to episodic cluster headaches. One participant, who received the greatest number of injections, developed avascular necrosis and the causal relationship with the suboccipital injections was not determined. The remainder of participants noted no major adverse events and clinicians noted only mild bone loss at the injection site.
Future studies need a standard protocol for pain descriptions and to evaluate if corticosteroids are necessary for relief in addition to the block or if the anesthetic block is effective on its own.
In conclusion, patients with refectory chronic cluster headaches were shown to find reliable pain relief from high-volume anesthetic suboccipital nerve blocks over a long-term follow-up.
The author noted no conflicts of interest.
Rozen, TD. High-volume anesthetic suboccipital nerve blocks for treatment refractory chronic cluster headache with long-term efficacy data: an observational case series study. [published online August 24, 2018]. Headache. doi: 10.1111/head.13394