Middle Meningeal Artery Embolization for Chronic Subdural Hematomas (STORMM) (STORMM)

Middle Meningeal Artery (MMA) Embolization for cSDH: Rationale and Design for the STOp Recurrence of MMA Bleeding (STORMM) Randomized-Control Trial

Chronic Subdural Hematomas (cSHD) are common, and due to cerebral compression, often result in neurological impairment and reduced consciousness. Surgery is typically performed once neurological symptoms develop. Recent studies suggest that arteries nourished by the middle meningeal artery (MMA) may be responsible for hematoma progression and that MMA embolization is clinically useful. There is less evidence, that embolization of MMA also may be a treatment option for individuals without surgical treatment. The investigators propose a multicentre study to investigate both potentials: (1) Assessment of efficacy of embolization after surgery to reduce recurrence and improve outcomes by conducting a randomized trial (randomization arms; Arms 1 and 2), (2) Assessment of embolization-alone efficacy when surgery is contraindicated or refused (embolization-only arm, Arms 3 and 4).

Study Overview

• Status: Recruiting
• Conditions: Chronic Subdural Hematomas; Cerebral Compression Due to Injury
• Intervention / Treatment: Radiation: MMA embolization

Detailed Description

Evidence to support the benefit of MMA embolization remains limited and the risk-benefit balance remains unclear. Case series have shown that recurrence rates with embolization are much lower, and that embolization is generally very safe. Risks associated with neurointerventional procedures will be directly discussed with patients or their caretakers as part of the conventional consenting procedure. Risks include access site hematoma, radiation exposure, vascular injury, brain ischemia, death (theoretic and extremely unlikely) and typical risks associated with general or local anaesthesia. The potential efficacy of MMA embolization as a treatment therefore requires higher level evidence in the form of randomized control trials.

The benefit of the embolization is a substantial reduction in recurrence of cSDH, which has been reported to be as high 1 in 3-4 patients. Recurrence of cSDH can lead to additional surgery and complications.

First objective: Evaluate the recurrence rates of cSDH after combined surgical and MMA embolization treatments (Arm 2) versus surgery alone (Arms 1).

Second objective: The second objective is to evaluate the stability and regression of cSDH after for all the Arms of the study at follow-up.

• Study Type: Interventional
• Enrollment (Estimated): 180
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Aria Nouri; Phone Number: +41795530958; Email: aria.nouri@hug.ch

Study Locations

• Switzerland
  • Geneva, Switzerland
    • Recruiting
    • Geneva University Hospitals
    • Contact: Aria Nouri
  • Lugano, Switzerland
    • Recruiting
    • EOC
    • Contact: Andrea Cardia; Phone Number: +41 (0)91 811 62 83; Email: andrea.cardia@eoc.ch

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age: 18-100
• Consent possible
• cSDH located at the convexities
• Patients with symptomatic cSDH
• Patients with asymptomatic large chronic/subacute hematoma after 6 weeks of failed conservative treatment

Exclusion Criteria:

• Consent not possible
• Pregnancy
• Prisoner
• Angiography contraindication
• Patient for whom follow-up is problematic (e.g. distant residency, homeless …)
• Previous surgery for cSDH

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Arm 1 - Surgery - No embolization (control); Patients who undergo surgical treatment will be randomized into receiving embolization within 72 hours post-surgery (Arm 2) or no-embolization post-surgery (conventional management, Arm 1). Patients will be randomized at rate of 2 MMA embolization to 1 conventional management.
Experimental: Arm 2 - Surgery - MMA embolisation; Patients who undergo surgical treatment will be randomized into receiving embolization within 72 hours post-surgery (Arm 2) or no-embolization post-surgery (conventional management, Arm 1). Patients will be randomized at rate of 2 MMA embolization to 1 conventional management.	Radiation: MMA embolization; Middle meningeal artery embolization
Active Comparator: Arm 3 - No surgery - Embolization accepted; Patients who are excluded for surgery due to significant medical contraindications or patients who refuse surgery, will be considered for embolization only. Embolization accepted : Arm 3.	Radiation: MMA embolization; Middle meningeal artery embolization
No Intervention: Arm 4 - No surgery - Embolization not accepted; Patients who are excluded for surgery due to significant medical contraindications or patients who refuse surgery, will be considered for embolization only. Embolization refused : Arm 4.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Recurrence of cSDH - 1	Surgical reoperation	6-months
Recurrence of cSDH - 2	Neurological deterioration due to a cSDH after evacuation	6-months
Recurrence of cSDH - 3	Post-operative hematoma volume of more than 90% of the preoperative volume at follow-up	6-months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Additional clinical outcomes - 1	Glasgow Coma Scale (Min=3; Max=15; Higher score=Best outcome)	6-months
Additional clinical outcomes - 2	modified Ranking Scale (Min=0; Max=6; Higher score=Worse outcome)	6-months
Additional clinical outcomes - 3	Markwalder Grading Scale (Min=0; Max=4; Higher score=Worse outcome)	6-months
Additional clinical outcomes - 4	Glasgow Outcome Scale - Extended (Min=1; Max=8; Higher score=Best outcome)	6-months
Additional clinical outcomes - 5	Karnofsky Performance Score (Min=20; Max=100; Higher score=Best outcome)	6-months
Additional clinical outcomes - 6	Therapy-Disability-Neurology grading system (Min=1; Max=5; Higher score=Worse outcome)	6-months
Additional clinical outcomes - 7	Mortality rate	6-months
Additional clinical outcomes - 8	Re-hospitalisation for all causes	6-months

Collaborators and Investigators

• Sponsor: University Hospital, Geneva
• Investigators: Principal Investigator: Aria Nouri, University Hospital, Geneva

Publications and helpful links

General Publications

• Al Awadhi A, Mollica C, Da Broi M, Molliqaj G, Hofmeister J, Rosi A, Bernava G, Machi P, Morel S, Cardia A, Meling TR, Schaller K, Nouri A. Middle meningeal artery (MMA) embolisation for chronic subdural haematomas: rationale and design for the STOp Recurrence of MMA Bleeding (STORMM) randomised control trial-a study protocol. BMJ Open. 2025 May 6;15(5):e092014. doi: 10.1136/bmjopen-2024-092014.

Study record dates

Study Major Dates

• Study Start (Actual): February 18, 2025
• Primary Completion (Estimated): January 1, 2027
• Study Completion (Estimated): January 1, 2027

Study Registration Dates

• First Submitted: November 20, 2023
• First Submitted That Met QC Criteria: November 30, 2023
• First Posted (Actual): December 11, 2023

Study Record Updates

• Last Update Posted (Actual): March 17, 2026
• Last Update Submitted That Met QC Criteria: March 16, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Wounds and Injuries; Pathologic Processes; Chronic Disease; Disease Attributes; Hemorrhage; Craniocerebral Trauma; Trauma, Nervous System; Intracranial Hemorrhages; Intracranial Hemorrhage, Traumatic; Pathological Conditions, Signs and Symptoms; Hematoma, Subdural; Hematoma; Hematoma, Subdural, Chronic
• Other Study ID Numbers: 2023-00848

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No