🧠 Recurrent Chronic Subdural Hematoma (rCSDH)

A 'recurrent chronic subdural hematoma' is the re-accumulation of blood in the subdural space after surgical evacuation of a previous chronic subdural hematoma. Recurrence typically occurs within weeks to months and affects 5–30% of cases depending on technique and patient factors.

Chronic subdural hematomas (CSDH) arise from venous bleeding (usually bridging veins), compounded by:

• Fragile neomembrane formation
• Inflammatory response and angiogenesis
• Ongoing fibrinolysis within the capsule

'Recurrence' occurs due to:

• Incomplete brain re-expansion
• Residual membranes or compartments
• Persistence of subdural space
• Coagulopathy or antithrombotic therapy

• Age > 75 years
• Antiplatelet/anticoagulant use
• Bilateral hematomas
• Low brain expansion post-op
• Large residual subdural cavity
• No drainage left post-op
• Non-irrigated burr holes
• Poorly controlled hypertension
• Chronic alcohol use or hepatic dysfunction

• Clinical: Return of symptoms (confusion, focal deficits, gait issues)
• Radiological:
  1. CT: hypodense/isodense collection with mass effect
  2. MRI: useful in atypical or recurrent cases

• Burr hole craniostomy (BHC) + closed drainage (24–48h)
• Twist-drill craniostomy in fragile patients
• Mini-craniotomy in multiloculated or recurrent cases

• Re-operation via burr hole or craniotomy
• Membranectomy if thickened capsule causes compartmentalization
• Middle Meningeal Artery Embolization (MMAE):
  1. Adjunct to surgery or alternative in high-risk cases
  2. Reduces recurrence by occluding capsule vascular supply

• Performed endovascularly via radial/femoral access
• Embolizes MMA branches feeding outer membrane
• Used as:
  1. Primary treatment in mild/recurrent cases
  2. Adjunct after evacuation to prevent recurrence
• Recurrence reduced to <10% in some studies

• Good overall outcome with prompt intervention
• Recurrence does not usually imply malignant course
• Prognosis worsens with:
  1. Baseline frailty
  2. Seizures
  3. Neurological deterioration at recurrence

Note: For decision algorithms or MMAE protocols, see middle_meningeal_artery_embolization or csdh.