Greater Occipital Nerve Block for Migraine Prophylaxis

Migraine is a common neurological condition that can be disabling, particularly if chronic. Greater occipital nerve (GON) block has been utilized for decades for the treatment of migraine in the absence of a single randomized, placebo-controlled trial documenting its effectiveness. Hypothesis: Greater occipital nerve block reduces the frequency of days with moderate or severe headache in patients with episodic or chronic migraine.

Migraine is a common disease with lifetime prevalence in women and men of 33% and 12% respectively. Chronic migraine affects 2% of the US population and is highly disabling. There are no FDA approved medications for the treatment of chronic migraine. Although some patients benefit from a daily prophylactic medication, others continue to suffer from severe, frequent, debilitating headaches. Limited efficacy, poor compliance, side effects and drug-drug interactions may explain why more than 80% of migraineurs in the population are not prescribed daily prophylactic medications. Occipital nerve injections with corticosteroids and/or local anesthetics have been employed for the acute and prophylactic treatment of migraine, cervicogenic headache and cluster headache for decades. A long-acting anesthetic and corticosteroid are often combined, although anesthetic agents have also been used alone. However, there are no randomized controlled trials evaluating the preventive efficacy of occipital nerve block in subjects with migraine. Patients were equally randomized to receive either 2.5 ml 0.5% bupivacaine plus 0.5 ml 20 mg methylprednisolone over the ipsilateral (unilateral headache) or bilateral (bilateral headache) occipital nerve or 2.75 ml normal saline plus 0.25 ml 1% lidocaine without epinephrine (placebo). The GON injection site was at the medial third of the distance between the occipital protuberance and the mastoid process. Patients were evaluated after the 4-week baseline diary completion phase to undergo the injection, and for 4 weeks after the injection. Therefore, there were 3 patient visits in this study: screening, injection and 4-week follow-up. In an effort to ensure adequate blinding, 0.25 ml of short-acting 1% lidocaine without epinephrine was used as the placebo arm. In order to ensure adequate blinding of the investigator, each syringe and needle hub was covered with opaque tape so as to ensure blinding of the investigator providing the injection. A total of four investigators provided injections. The blinded investigator who evaluated the study subject 4 weeks after injection may or may not be the same as the investigator who provided the injection.

Subjects randomized to this arm will receive 2.5 mL 0.5% bupivicaine plus 0.5 mL 20 mg methylprednisolone injected over the ipsilateral (unilateral headache) or bilateral (bilateral headache) occipital nerve.

Subjects randomized to this arm will receive 2.75 mL normal saline plus 0.25 mL 1% lidocaine injected over the ipsilateral (unilateral headache) or bilateral (bilateral headache) occipital nerve.

Number of Subjects With at Least 50% Reduction in the Frequency of Days With Moderate or Severe Migraine in the 4 Week Post Injection Compared to the 4 Week Pre-injection Baseline Period

The baseline frequency will be the number of calendar days with moderate or severe migraine during the 4 week period prior to injection, and the follow-up frequency will be the number of calendar days with migraine during the 4 week period following injection.

Inclusion Criteria: Subjects meet diagnostic criteria for episodic migraine or chronic migraine according to the International Headache Classification II (ICHD-II) Migraine sufferers who experience at least 1 attack per week Able to read and understand the requirements of the study, abide by any restrictions, and return for the required examinations Able and willing to sign an informed consent statement Subjects must be in generally good health as confirmed by medical history, medication review, baseline physical examination, vital signs and clinical laboratory evaluations. Exclusion Criteria: Subjects with continuous headache (no headache free periods) Subjects using maintenance opioid medication Subjects who have started a medication with prophylactic migraine efficacy within the past 2 months Known hypersensitivity or allergic reaction to any of study ingredients (lidocaine, bupivicaine, any local anesthetics, and corticosteroids) or betadine. Use of any investigational medication within 90 days of the initial screening visit and/or concurrent enrolment in an investigational study Injection site infection or systemic infection at the injection visit (afebrile at time of injection) Presence of cranial bone defect Subjects with chronic cluster headache, new daily persistent headache, hemicrania continua, or chronic tension type headache Subjects with a history of an unstable medical condition (e.g. cardiovascular, hepatic, renal, endocrine) that may impair their reliable participation in the study or necessitate the use of medications not permitted in this study Subjects with a history (within the past 6 months) of a major psychiatric disorder that in the opinion of the investigator may preclude the subject from completed the requirements of the study Female subjects who are pregnant or nursing Subjects with a history of drug or alcohol abuse within the past 2 years Subjects with a history of poor compliance with past drug therapies, as judged by the investigator.

Dilli E, Halker R, Vargas B, Hentz J, Radam T, Rogers R, Dodick D. Occipital nerve block for the short-term preventive treatment of migraine: A randomized, double-blinded, placebo-controlled study. Cephalalgia. 2015 Oct;35(11):959-68. doi: 10.1177/0333102414561872. Epub 2014 Dec 12.