Frontal vs Parietal Eminence Drainage for Chronic Subdural Hematoma

This is a (multi-center) prospective, randomized, parallel-group, assessor-blinded clinical trial in eligible patients with unilateral chronic subdural hematoma (cSDH) to compare the effects of puncture-site location on outcomes after minimally invasive drainage: participants will be randomly assigned 1:1 to Group A (frontal twist-drill puncture drainage) or Group B (parietal eminence twist-drill puncture drainage), with both groups receiving standardized closed-system subdural drainage and postoperative management; random allocation will be concealed using a secure electronic randomization system or sealed opaque envelopes prepared by a researcher not involved in surgery or outcome assessment. The primary outcome is the rate of ipsilateral cSDH recurrence requiring reoperation within 3 months after surgery (recurrence defined as symptomatic re-accumulation or enlargement confirmed by imaging and judged by the treating team to require repeat intervention). Secondary outcomes include postoperative residual hematoma maximum thickness and volume at 24-48 hours, pneumocephalus volume at 24-48 hours, reduction in midline shift, brain re-expansion rate, drainage duration, length of hospital stay, postoperative complications, Markwalder grading and modified Rankin Scale (mRS) scores at 30 days/3 months, and mortality at 30 days and 3 months; although surgeon blinding is not feasible, radiological and clinical outcome assessors and statisticians will be blinded whenever possible, with anonymized postoperative CT images assessed independently by trained reviewers.

Inclusion criteria

• Age ≥ 18 years.
• Unilateral chronic subdural hematoma (cSDH) or subacute-to-chronic subdural hematoma, confirmed by CT or MRI.
• Presence of clinical symptoms attributable to cSDH, such as headache, limb weakness, gait disturbance, cognitive decline, speech disturbance, seizure, or impaired consciousness.
• Radiological indication for surgery, defined as one of the following:

Maximum hematoma thickness ≥ 10 mm, and/or Midline shift ≥ 5 mm, or Even if these thresholds are not met, clinically significant symptoms requiring surgery as judged by the treating neurosurgeon.

• Plan to undergo twist-drill puncture drainage with a closed drainage system.
• Written informed consent signed by the participant or their legally authorized representative.

Exclusion criteria

• Bilateral cSDH requiring simultaneous bilateral surgery.
• Acute subdural hematoma, or a condition where the hematoma is predominantly composed of an acute hemorrhagic component.
• Markedly septated, organized, or calcified hematoma in which minicraniotomy or craniotomy is required preoperatively.
• Previous surgery on the ipsilateral side for cSDH.
• Concomitant intracranial conditions requiring specific treatment, including but not limited to: intracranial tumor, brain abscess, vascular malformation, or ruptured aneurysm.
• Severe coagulation disorder that cannot be corrected before surgery.
• Life expectancy < 6 months.
• Pregnancy.
• Any condition that, in the judgment of the investigator, makes the patient inappropriate for participation in the study.