Chronic subdural hematoma
A collection of liquefied blood between the dura and arachnoid that develops over weeks after often-trivial or forgotten trauma, typically in elderly or anticoagulated patients with cerebral atrophy; CT confirms the diagnosis, and burr-hole drainage is the treatment for a symptomatic hematoma with significant thickness or midline shift.
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What this article covers
- Overview
Definition: chronic subdural hematoma (cSDH) is a collection of liquefied, often membrane-encapsulated blood in the subdural space (between the dura mater and arachnoid) that develops days to weeks…
- Epidemiology
Predominantly a disease of older adults, reflecting the age-related cerebral atrophy that predisposes to bridging vein rupture from even minor trauma.
- Risk factors
Advanced age: cerebral atrophy increases the subdural space and tension on bridging veins, the central predisposing mechanism.
- Pathophysiology
Bridging vein rupture: trauma, even minor, shears the bridging veins that cross the subdural space from the cortical surface to the dural venous sinuses; in an atrophic brain these veins are already…
- Clinical features
Nonspecific presentation: headache, altered mental status, or somnolence are the most common findings, often mistaken initially for dementia, stroke, or a metabolic disturbance in an older patient.
- Differential diagnosis
Acute subdural hematoma: presents with coma or rapid neurologic compromise within hours of major trauma, versus the gradual, weeks-long evolution after trivial or forgotten trauma seen in chronic subdural hematoma.
- Diagnosis
Establishing the diagnosis: noncontrast head CT showing a crescent-shaped extra-axial collection along the cerebral convexity that is hypodense (older blood) or of mixed/isodense density (recent…
- Management
First step: reverse any anticoagulation or coagulopathy urgently once the diagnosis is made and before proceeding to intervention, using the specific reversal agent for the anticoagulant involved…
- Complications
Recurrence: chronic subdural hematoma recurs after drainage in a meaningful minority of patients, particularly with incomplete evacuation, ongoing anticoagulation, or a persistent membrane.
- Prognosis
Generally favorable with timely drainage: most patients who undergo burr-hole evacuation for a symptomatic hematoma show substantial clinical improvement.
- Prevention
Fall-risk reduction in older adults: annual fall-risk screening in adults age 65 and older, with home safety assessment, gait and balance evaluation, and treatment of contributing factors…
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Related articles
- Acute subdural hematoma
Acute subdural hematoma is venous bleeding between the dura and arachnoid membrane from ruptured bridging veins, producing a crescent-shaped collection that crosses suture lines on CT. Older adults and patients with alcohol use disorder or on anticoagulation are most susceptible; a hematoma over 10 mm, a GCS under 9, or pupillary asymmetry mandate immediate surgical evacuation.
- Epidural hematoma
Epidural hematoma is an arterial bleed, classically from the middle meningeal artery after a temporal bone fracture, that collects between the skull and dura in a biconvex shape that does not cross suture lines; a lucid interval followed by rapid decline is classic, and a GCS below 9, anisocoria, or hematoma over 30 mL requires urgent surgical evacuation.
- Traumatic brain injury
Traumatic brain injury is structural or functional brain damage from biomechanical force, graded moderate (Glasgow Coma Scale 9-12) or severe (Glasgow Coma Scale 3-8) when imaging shows contusion, edema, or hemorrhage; management centers on preventing hypotension and hypoxia, controlling intracranial pressure with hyperosmolar therapy and, when refractory, decompressive craniectomy.
- Increased intracranial pressure
Sustained intracranial pressure above 20-22 mmHg from mass effect, edema, hydrocephalus, or venous outflow obstruction, diagnosed by clinical signs plus invasive monitoring and treated stepwise with head elevation, hyperosmolar therapy (mannitol or hypertonic saline), CSF diversion, and decompressive surgery when refractory.