BURR-MMA: A Prospective Pilot Feasibility Study of Intra-operative Middle Meningeal Artery Coagulation During Burr-Hole Surgery for Chronic Subdural Haematoma
Overview
- Phase
- Not Applicable
- Status
- Not yet recruiting
- Sponsor
- University College, London
- Enrollment
- 30
- Primary Endpoint
- Technical Success of the MMA Adjunct
Overview
Brief Summary
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.
Detailed Description
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.
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Treatment
- Masking
- None
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
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.
Arms & Interventions
Burr-Hole Evacuation With CT-Guided Intra-Operative MMA Interruption
Participants in this single-arm feasibility study will undergo standard burr-hole evacuation of chronic subdural haematoma with subdural drain placement, in accordance with routine clinical practice. In addition, a CT- and neuronavigation-guided intra-operative adjunct will be attempted to identify and interrupt distal convexity branches of the middle meningeal artery (MMA) supplying the haematoma membrane, where this is considered safe and technically feasible by the operating surgeon.
The adjunct involves minor adjustment of burr-hole position within the haematoma footprint and limited bipolar coagulation of target MMA branches. If safe identification or access is not possible, the adjunct will be omitted and standard surgery completed.
All imaging and peri-operative care are part of standard clinical practice. The study is designed to assess feasibility, safety, procedural fidelity and workflow integration rather than clinical effectiveness.
Intervention: CT-Guided Intra-Operative Middle Meningeal Artery Interruption (Procedure)
Outcomes
Primary Outcomes
Technical Success of the MMA Adjunct
Time Frame: Intra-operative (during index procedure) and on first post-operative non-contrast CT, up to 72 hours post-operatively.
Proportion of procedures in which one or more intended distal convexity MMA branches are successfully identified and coagulated by the operating surgeon, confirmed intra-operatively and by post-operative non-contrast CT showing burr-hole placement over the expected MMA bony groove. Reported as a percentage (0-100%); higher values indicate greater technical deliverability.
Incidence of Technique-Related Adverse Events
Time Frame: Intra-operative through 90 days post-operatively.
Number of participants experiencing at least one adverse event judged by the investigator to be related to the MMA adjunct (e.g., thermal injury, additional bleeding, equipment-related events). Reported as a count and percentage of enrolled participants.
Incidence of Serious Adverse Events
Time Frame: From index procedure through 90 days post-operatively.
Number of participants experiencing at least one serious adverse event (as defined by ICH-GCP), regardless of causality. Reported as a count and percentage of enrolled participants
Completeness of Day-90 Outcome Data Capture
Time Frame: At 90 days post-operatively.
Proportion of enrolled participants with complete primary outcome data available at the Day-90 follow-up, against a pre-specified feasibility target of ≥95%. Reported as a percentage.
Secondary Outcomes
- Incidence of cSDH Recurrence Requiring Re-Intervention(Up to 90 days post-operatively)
- Length of Hospital Stay(During index admission (up to discharge, assessed up to 90 days post-operatively).)
- Incidence of Peri-Operative Complications(Intra-operative through 30 and 90 days post-operatively.)
- Incidence of Unplanned Hospital Readmission(From discharge through 90 days post-operatively.)
- Functional Outcome Measured by the Modified Rankin Scale (mRS)(At 90 days post-operatively.)
- Health-Related Quality of Life Measured by the EQ-5D-5L Utility Index(At 90 days post-operatively.)
- Added Operative Time Attributable to the MMA Adjunct(Intra-operative (during index procedure).)
- Procedural Fidelity to the Pre-Specified Surgical SOP(Intra-operative (during index procedure).)
- Learning Effect on Added Operative Time Across Sequential Cases(Through study completion (up to 12 months).)
- Concordance Between Pre-Operative CT MMA Groove and Intra-Operative Findings(Intra-operative (during index procedure), compared against pre-operative CT performed within 7 days prior to surgery.)
- Feasibility of Prospective Healthcare Resource-Use Data Collection(Through 90 days post-operatively.)