Middle Meningeal Artery Embolization for Chronic Subdural Hematomas (STORMM)

Study Overview
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Brief Summary
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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).

Detailed Description
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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.

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

Conditions
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Chronic Subdural Hematomas, Cerebral Compression Due to Injury

Intervention / Treatment
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* Radiation: MMA embolization


Participation Criteria
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Eligibility Criteria
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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

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: This study is a multicentre randomised-controlled trial.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Arm 1 - Surgery - No embolization (control)<br>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<br>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<br>* Middle meningeal artery embolization<br>|
| Active Comparator: Arm 3 - No surgery - Embolization accepted<br>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<br>* Middle meningeal artery embolization<br>|
| No Intervention: Arm 4 - No surgery - Embolization not accepted<br>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?
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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 |