Subarachnoid hemorrhage (SAH) is a type of bleeding around the brain that can cause sudden and severe headaches. These headaches can be debilitating and persist for weeks, significantly impacting a patient's comfort and recovery. Many patients require opioids for pain control, which can lead to side effects such as drowsiness, constipation, and dependency. There is a need for new treatment strategies to help relieve this pain while minimizing side effects.

This clinical study is designed to evaluate whether an injection of two medications (lidocaine and methylprednisolone) directly into the middle meningeal artery (MMA) can help reduce headache severity in patients who recently experienced a SAH. The medications will be given through a minimally invasive procedure performed during a routine angiogram, a type of imaging test already commonly used in SAH patients. The main goals of the study are to determine whether this treatment approach is safe, helps to reduce the severity of headaches, and decreases the need for opioid pain medications. Eligible patients will be those recently diagnosed with persistent headache symptoms and SAH who are undergoing routine cerebral angiogram, during which the medications are infused into the MMA. Participants will be monitored for pain levels using the Headache Impact Test (HIT-6) and 11-point Numeric Rating Scale (NRS), and for changes in their functional recovery using standard neurologic scales. The results of this study may provide early evidence to support new treatment options for patients suffering from difficult-to-control headaches after a SAH.

This is a single-center, prospective, single-arm, open-label clinical trial evaluating the safety and efficacy of intra-arterial administration of lidocaine and methylprednisolone sodium succinate via the MMA for the treatment of moderate or severe headaches associated with SAH. Eligible participants will include adult patients diagnosed with SAH who are undergoing diagnostic or therapeutic digital subtraction angiography (DSA). During the DSA procedure, following routine angiographic imaging, a microcatheter will be placed in the MMA, and a low dose of lidocaine and methylprednisolone will be slowly infused under fluoroscopic guidance.

The primary outcome will assess the change in headache severity and intensity using the HIT-6 score and 11-point NRS at baseline (pre-intervention), discharge, and at follow-up visits at days 1-10, Weeks 2, 4 and 12. Secondary outcomes will include reduction in opioid use, neurological outcome measured by the modified Rankin Scale at discharge and follow-up, and the incidence of any adverse events related to the procedure.

Inclusion Criteria:

1. Adults aged ≥18 years with confirmed SAH via computed tomography or magnetic resonance imaging
2. Undergoing DSA as part of routine diagnostic or therapeutic care
3. Experiencing headaches with baseline severity assessable using Headache Impact Test (HIT-6) questionnaire and 11-point Numeric Rating Scale (NRS)
4. Conscious patients who can understand and sign informed consent form
5. Hemodynamically stable and suitable for intra-arterial procedures

5) Willingness to comply with study procedures and follow-ups

Exclusion Criteria:

1. Known allergy or hypersensitivity to lidocaine or amide-type anesthetics
2. Known allergy or hypersensitivity to Intralipid® (intravenous fat emulsion) or any of its components, including egg phospholipids or soy-based products
3. Known allergy or hypersensitivity to methylprednisolone, corticosteroids, any component of the Solu-Medrol® formulation
4. Diagnostic abnormalities at baseline, including ECG abnormalities (e.g., prolonged PR/QTc intervals, heart block, arrhythmias)
5. Cardiac conditions including history of heart block, Stokes-Adams syndrome, Wolff-Parkinson-White syndrome, or use of antiarrhythmics
6. Steroid-induced psychiatric history; uncontrolled seizures; uncontrolled diabetes; glaucoma/ocular hypertension; current/recent high-dose systemic steroids.
7. Previous IA lidocaine or methylprednisolone (or similar) therapy prior to enrollment
8. Alternative headache etiology (e.g., migraines, tension-type headache)
9. Unable to report pain reliably due to severe cognitive or communication deficits
10. Severe hemodynamic instability precluding safe DSA participation
11. Contraindications to IA catheterization or DSA (e.g., severe peripheral vascular disease, contrast allergies)
12. Severe renal impairment (eGFR <30 mL/min/1.73 m²)
13. Severe hepatic impairment (e.g., Child-Pugh Class C)
14. Active systemic infections
15. Severe comorbid conditions with life expectancy <30 days
16. Participants who are pregnant or breastfeeding
17. Conditions or concomitant medications listed in the USPI for study drugs that would compromise safety or data quality
18. Current participation in another clinical trial