Middle Meningeal Artery Coagulation During Burr-Hole Drainage for Chronic Subdural Haematoma (BURR-MMA)

BURR-MMA: A Prospective Pilot Feasibility Study of Intra-operative Middle Meningeal Artery Coagulation During Burr-Hole Surgery for Chronic Subdural Haematoma

Chronic subdural haematoma (cSDH) is a common condition in older adults, usually treated by burr-hole surgery to drain the collection. Even with good surgery, around 1 in 10 patients develop a recurrence and need a second operation. Research shows that the outer lining of the haematoma is fed by small branches of the middle meningeal artery (MMA), and interrupting these branches may lower the risk of recurrence.

This study looks at whether surgeons can safely and reliably coagulate these small MMA branches at the same time as standard burr-hole drainage, using the routine pre-operative CT scan and surgical navigation already used in everyday practice. Adults (aged 18 years and over) scheduled for burr-hole drainage of a chronic or subacute subdural haematoma will be invited to take part. The procedure, recovery, drain management, and 90-day follow-up will otherwise follow standard NHS care.

No additional imaging is required for the study, and participants are not exposed to any extra radiation. The main purpose is feasibility and safety, not to prove effectiveness. Findings will inform the design of a future multicentre study.

Recurrence after burr-hole drainage of chronic subdural haematoma is driven largely by a vascularised outer membrane supplied by distal convexity branches of the middle meningeal artery. Endovascular MMA embolisation can reduce recurrence but requires a separate interventional radiology procedure and is not uniformly available across NHS centres.

BURR-MMA evaluates an alternative, in-workflow approach: limited bipolar coagulation of distal convexity MMA branches performed through the planned burr-hole during standard evacuation. Pre-operative non-contrast CT is used to map the MMA bony groove, and routine CE-marked neuronavigation is used to standardise targeting. No additional burr-holes, implants, drugs, or research-specific imaging are introduced.

This is an IDEAL Stage 2a, single-centre, single-arm feasibility study enrolling 20-30 adults undergoing burr-hole surgery for cSDH. The primary focus is technical deliverability, safety, procedural fidelity, and characterisation of iterative technique refinement. Exploratory clinical outcomes are collected to Day 90 to inform endpoint selection and sample-size calculations for a future IDEAL Stage 2b multicentre cohort study. All CT imaging is performed as part of routine clinical care; participants receive no additional ionising radiation because of study participation. The study is not powered to assess clinical effectiveness.

Inclusion Criteria:

• Age ≥18 years.
• Chronic or subacute subdural haematoma scheduled for burr-hole evacuation.
• Treating surgeon considers the CT- and navigation-guided MMA adjunct technically feasible and safe to attempt, recognising that the adjunct may be abandoned intra-operatively according to protocol bail-out criteria.
• Written informed consent, or consultee declaration under the Mental Capacity Act (MCA), with re-consent if capacity returns.

Consented participants who meet eligibility criteria will be enrolled sequentially until the target sample size of 20-30 participants is reached. No randomisation is used in this feasibility phase.

Exclusion Criteria:

• Acute subdural haematoma requiring craniotomy or decompressive surgery.
• Prior ipsilateral MMA embolisation.
• Clear contraindication to pre-operative CT
• Inability to complete Day-90 follow-up.
• Pregnancy or breastfeeding (due to radiation exposure from CT imaging as part of standard clinical care).

If CT is non-diagnostic or cannot be performed, participants will continue with standard burr-hole evacuation without the MMA adjunct; this does not constitute a protocol deviation.