Known hypersensitivity and/or contraindication to lidocaine or local anesthetics of the amide type
Taking chronic medications that, when co-administered with lidocaine and other local anesthetics, are at increased risk of developing methemoglobinemia (nitrates/nitrites, local anesthetics, antineoplastic agents, antibiotics, antimalarials, anticonvulsants, acetaminophen, metoclopramide, quinine, sulfasalazine)
Known contraindications for angiography (eg, ESRD not requiring hemodialysis). Patients with contrast allergy with be premeditated with diphenhydramine and steroids.
Contraindication to anesthetic agents used for conscious sedation/monitored anesthesia care (MAC)
Concurrent participation in another research protocol for investigation of an experimental therapy
Per DSA imaging, presence of a cerebrovascular pathology known to cause headache (eg, arteriovenous malformation, dural arteriovenous fistula)
Per DSA imaging, presence of anastomosis or anatomical variation (eg, branches of middle meningeal artery) that could lead to increased procedural risk
Per DSA imaging, lack of endovascular access to either middle meningeal artery, or origin of the middle meningeal artery other than from the external carotid artery
Known or suspected inability to adhere to study protocol or protocol requirements, as per discretion of the Investigator or treating provider
