Swedish Trial on Embolization of Middle Meningeal Artery Versus Surgical Evacuation in Chronic Subdural Hematoma

Study Overview
=================
Brief Summary
-----------------
The SWEMMA trial is an open, national, multi-center, prospective, randomized (1:1), superiority trial designed to assess impact on reoperation rates for chronic subdural hematoma with a head-to-head comparison of embolization of the middle meningeal artery (intervention) with standard neurosurgical hematoma evacuation (control).

Detailed Description
-----------------
Introduction: Chronic subdural hematoma (CSDH) is one of the most common neurosurgical disorders and the incidence is rising. The mainstay of treatment is neurosurgical hematoma evacuation followed by postoperative drainage but recurrence and reoperation rates are as high as 10-30%. Embolization of the middle meningeal artery (EMMA) has been proposed as an adjunct or as sole therapy and initial data suggests markedly reduced reoperation rates. Several randomised trials are currently underway, mostly randomizing with EMMA as an adjunctive to evacuation, or as an alternative to conservative treatment. This trial aims to make a head-to-head comparison of neurosurgical evacuation versus EMMA. Aims: The primary objective of the trial is to compare efficacy of EMMA on rates of reoperation by randomizing patients with CSDH and mild to moderate symptoms to either EMMA or standard neurosurgical evacuation. Secondary objectives include all complication rate, technical success rate, residual hematoma volume at 3 months, neurological functionality and quality of life at 3 and 12 months and composite endpoint of death or reoperation at 3 and 12 months. Method: Patients with previously untreated CSDH admitted to the neurosurgical unit at participating centers with clinical and/or radiological indication for neurosurgical evacuation, mild to moderate symptoms and able to provide informed consent, will be randomized to either standard treatment or EMMA. Immediately after either procedure the participant returns to standard clinical care. At 3 months a CT of the head is performed. A structured telephone interview is held by a treatment-blinded outcomes assessor at 3 months and 12 months, measuring quality of life (EQ-5D) and neurological disability (mRS). Medical records are collected and assessed at 3 months regarding safety measures. Data on reoperation and mortality are collected from the National Board of Health and Welfare and National Cause of Death Registry at 3 months and 12 months.

Official Title
-----------------
Swedish Trial on Embolization of Middle Meningeal Artery Versus Surgical Evacuation in Chronic Subdural Hematoma

Conditions
-----------------
Chronic Subdural Hematoma

Intervention / Treatment
-----------------
* Procedure: Endovascular treatment of the middle meningeal artery
* Procedure: Standard neurosurgical hematoma evacuation


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Men and women 18-89 y/o Non-contrast Computed Tomography (NCCT)- or Magnetic Resonance Imaging (MRI)- verified, previously unoperated uni- or bilateral cSDH Clinical and/or radiological status indicating neurosurgical treatment Markwalder Scale score <2 Glasgow coma Scale score >13 Able to provide signed informed consent Exclusion Criteria: Acute subdural hematoma Focal, non-hemispheric cSDH Midline shift >10 mm and/or effaced basal cisterns and/or significant dilatation of one or both lateral ventricle temporal horns and/or incipient uncal herniation Structural pathology causing the cSDH (e.g. dural AV-fistula, AVM, tumor, arachnoid cyst, ventriculoperitoneal shunt) Contraindications to angiography Dependency defined as mRS >3 Life expectancy <6 months Comorbidity deemed making follow up impossible Participation in other interventional clinical study Pregnancy

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 89 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Embolization of middle meningeal artery<br>Participants receive endovascular treatment with embolization of the middle meningeal artery ipsilaterally to the chronic subdural hematoma(s). | Procedure: Endovascular treatment of the middle meningeal artery<br>* The middle meningeal artery on the same side(s) as the chronic subdural hematoma is embolized with liquid embolic agents.<br>|
| Active Comparator: Standard neurosurgical hematoma evacuation and drainage<br>Participants receive standard neurosurgical hematoma evacuation via burr hole or mini craniotomy and post-operative subdural or subgaleal drainage. | Procedure: Standard neurosurgical hematoma evacuation<br>* Standard neurosurgical evacuation of chronic subdural hematoma through burr-hole or mini craniotomy and postoperative subdural or subgaleal drainage.<br>* Other names: burr-hole, mini craniotomy;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reoperation | Reoperation rate of CSDH between groups | 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Neurological disability | Assessed by the modified Rankin Scale (mRS). Numerical scale with scores between 0 and 6 (0 = no symptoms, 6= death) | 3 months and 12 months | 
| Quality of Life (EQ-5D) | Assessed by the EuroQol EQ-5D scale | 3 months and 12 months | 
| Residual hematoma volume | Change in hematoma volume from pre-, post operative, and follow up head CT | 3 months | 
| Technical success rate | Rate of technically successful embolizations performed | 24 hours | 
| Procedure related complication rate (Safety) | Difference in number and severity of complications between endovascular and surgical participants | 3 months | 
| Composite endpoint | Death or reoperation | 3 and 12 months |