Bilateral Middle Meningeal Artery Lidocaine Infusion for Chronic Debilitating Migraines

Inclusion Criteria:

1. Adults aged 18 to 75 years with a very severe to extremely severe medically refractory Chronic Daily Headache (CDH).

   1. Chronic: as defined by the International Headache Society Classification ICHD 3 (\>15 headache days a month for a period of at least 3 months)
   2. Medically refractory: defined as failure of ≥3 headache preventative treatments.
   3. Severely disabling (Migraine Disability Assessment \[MIDAS\] Tool score of ≥ 21 \[Grade IV\])
   4. Score of 6 (very severe) or 7 (extremely severe) on the Global Assessment of Migraine Severity (GAMS) rating scale.
   5. Head pain is at least moderate-to-severe intensity (\>5 on a Visual Analog Scale) in ≥50% of headaches.
2. Diagnosis of CDH for ≥ 12 months before screening based on medical records and/or patient self-report.
3. Headache frequency: minimum 15 monthly headache days (MHD) on average across the 3 months prior to screening
4. Patient reports to their provider intolerance or insufficient response with their current preventive treatment (i.e. insufficient reduction in headache frequency, duration, and severity on a standard treatment on a generally accept therapeutic dose for 6 weeks).
5. On a stable concomitant medication and headache preventive for the 3 months prior to screening

During Baseline Period:

1. Must have ≥ 15 MHD based on the patient self-maintained diary data during the baseline period.
2. Must have demonstrated \>75% compliance with diary data for the 28 day duration period, or longer if their baseline period carries on past this point.
3. Must continue to meet eligibility criteria when reassessed at baseline completion visit

Exclusion Criteria:

1. Recently started new migraine preventative treatment regimen within the past 3 months.
2. Known allergy or sensitivity to lidocaine.
3. Lidoderm patch (not an exclusion if the Lidoderm patch has been removed for ≥ 3 days before the procedure)
4. Severe allergy/anaphylaxis to iodinated contrast dye.
5. Any intracranial pathology on brain imaging (head CT or MRI within the past 12 months)
6. Chronic subdural hematoma
7. Ischemic stroke or myocardial infarction within 3 months 8. History of renal insufficiency with Cr \> 1.5 within 3 months (will be retested during pre-surgical

testing).

9\. History of abnormal ECGs within 3 months, specifically:

1. Prolonged QT syndrome
2. Use of medications that may prolong the QT interval such as: anti-nausea, anti-emetics, etc.

   10\. Taking any antiarrhythmic medication (other than a beta blocker)

   11\. Symptomatic peripheral arterial disease

   12\. Known inherited or acquired bleeding diathesis (not including antiplatelet or anticoagulation medication)

   13\. Evidence of active substance-related disorders, addictive disorders, or "recreational use" of illicit drugs.

a. If any of these disorders have occurred within 12 months prior to screening, based on medical records, patient self-report, or positive urine drug test (except for prescribed medications that may result in a positive urine drug test).

14\. Active chronic pain syndromes (e.g., fibromyalgia and chronic pelvic pain).

15\. History of major psychiatric disorder or current evidence of moderately severe or severe depression based on a Patient Health Questionnaire-9 (PHQ-9) total score ≥ 15 at screening.

a. Subjects with history of anxiety disorder and/or major depressive disorder with PHQ-9 \< 15) and are taking no more than 1 medication, for each disorder, for at least 2 months prior to screening may be considered.

16\. If the subject is pregnant, planning on pregnancy during the duration of the study, or planning on making their partner pregnant will be excluded from the study unless proper contraception is in place.

17\. Any diagnosis at the discretion of the investigator that would make the patient unfit.