Chronic Subdural Hematoma

Authors:

Manish KC,

Junaid Siddiquie, MD, MRCP

Introduction

• Slow extravasation of blood into the subdural space between the dura and arachnoid membranes

• Commonly seen neurosurgical condition associated with high morbidity and mortality

Epidemiology

• Worldwide Incidence
• 3-4/100,000/year in patients <65 years of age
• 8-58/100,000/year in patients >65 years of age
• 286/100,000/year in patients >80 years of age
• May occur after weeks of minor head injury (usually >3 weeks)

• Usually affects elderly and those on anticoagulant therapy

• Estimated to affect 60,000 US population >65 years of age annually by 2030

• Male to female ratio: 3:1

• Bilateral in 20%

Etiology

• Rupture of bridging veins

• Risk factors
• Old age
• Anticoagulant/antiplatelet therapy
• Male gender
• History of falls
• Minor head trauma
• Bleeding disorders
• Seizure history
• Alcohol use

Figure 1: Chronic Subdural Hematoma on CT

Pathophysiology

• Initial trauma to the subarachnoid space leading to acute SDH→ fibrin accumulates→ organization, dissolution of fibrin and subdural hematoma→ activate inflammatory changes lead to collagen and fibroblast formation→ subdural neomembrane formation in more than 2 weeks→ formation of weak vascular capillaries that promote subsequent chronic subdural hematoma

• Subdural hygroma: accumulation of CSF in the subdural space→ new blood vessel formation takes place→ bleeding from these newly formed vessels lead to the development of chronic subdural hematoma

Clinical Features

• Headache

• Nausea/vomiting

• Mental status changes
• Disorientation.
• Lethargy
• Cognitive dysfunction (a cause of reversible dementia-like symptoms)
• Delirium
• Coma

• Seizures

• Focal neurological deficits
• Motor weakness
• Hemiparesis
• Hemisensory loss
• Speech problems

• Difficulty walking

• Stroke

Clinical progression

• The early period of injury
• Traumatic brain injury causes hematoma development, also known as “seed” for chronic SDH

• The latent period of hematoma growth
• Hematoma grows slowly
• Volume expansion
• Significant neovascularization
• Lasts weeks to years
• Usually asymptomatic

• The Period of clinical appearance
• Clinical manifestations from raised intracranial pressure by enlarging hematoma.
• Seizures
• Coma
• Brain herniation

Differential Diagnosis

• Lymphoma

• Metastasis

• Sarcoma

• Infectious
• Neurocysticercosis
• Bacterial empyema

• Autoimmune disorders:
• Wegener granulomatosis
• Rosai-Dorfmann disease
• Polyarteritis nodosa

Diagnosis

• CT Scan of Head: hypodense crescent-shaped mass but can be isodense or hyperdense

• Additional CT findings
• Grey-white junction shifts medially
• Convexity sulci do not extend to the inner part of the skull

• MRI of Brain
• May be used when alternative diagnoses are suspected

Treatment

• Focused physical examination

• Pupillary examination and GCS assessment

• Emergent resuscitation with assessment of airway, breathing, and circulation., followed by emergent neuroimaging (CT head without contrast)

• Neurosurgical consultation

• Adequate intravenous access

• Coagulopathy correction/reversal

• Steroids medications

• Antiepileptic medications: Phenytoin/fosphenytoin or Levetiracetam

• Non-operative treatment: indicated in
• Asymptomatic patients with small hematoma
• Moribund patients with poor baseline function

• Indication for Surgical intervention
• Any size that is symptomatic
• Radiological signs of significant brain compression
• Radiological signs of impending midline shift
• Radiologically more than 2mm

• Surgical Technique
• Burr hole craniotomy
• Most commonly used.
• Drilling burr hole over cerebral convexity.
• 2 burr holes 5-8cm apart are drilled.
• Dura is entered and irrigated with normal saline.
• Silicone drainage is placed into the subdural space and drainage is done by connecting to a drainage system.
• Drain removed after 48 hours.
• Done under general anesthesia.
• Twist drill craniotomy.
• Relatively safe and less invasive method.
• A small craniotomy is made using a hand drill.
• Done under local anesthesia.
• Higher recurrence rate.
• Craniotomy.
• Most invasive method used in the past.
• Used for old, organized, multiseptated SDH.
• Large bone flap is separated followed by irrigation and evacuation of the hematoma.
• Higher morbidity than other surgical procedures.

Complications

• Recurrence

• Seizures

• Subdural empyema

• Intracerebral hemorrhage

• Epidural hematoma

• Pneumocephalus

• Intracerebral abscess

• Meningitis

Prognosis

• Good clinical outcome after surgery in 80-90% of patients

• Death rate: 0.5-4.3%

• Recurrence rate nearly 70%

• 10-20% of recurring cases require repeated surgical management

Bibliography

• Asghar M, Adhiyaman V, Greenway MW, Bhowmick BK, Bates A. Chronic subdural haematoma in the elderly: a North Wales experience. J R Soc Med 2002;95:290–292.

• Bourgeois P, Sleiman M, Louis E, et al. Chronic subdural hematoma in patients over 80 years of age [in French]. Neurochirurgie 1999;45:124–128.

• Cousseau DH, Echevarria Martin G, Gaspari M, Gonorazky SE. Chronic and subacute subdural haematoma: an epidemiological study in a captive population [in Spanish]. Rev Neurol 2001;32:821–824.

• Adhiyaman V, Asghar M, Ganeshram KN, Bhowmick BK. Chronic subdural haematoma in the elderly. Postgrad Med J 2002;78:71–5.

• Santarius T, Kirkpatrick PJ, Ganesan D, Chia HL, Jalloh I, Smielewski P. Use of drains versus no drains after burr-hole evacuation of chronic subdural haematoma: a randomised controlled trial. Lancet (London, England) 2009;374:1067–73.

• Asghar M, Adhiyaman V, Greenway M, Bhowmick BK, Bates A. Chronic subdural haematoma in the elderly—a North Wales experience. Journal of the royal society of medicine. 2002;95(6):290-2.

• Miranda LB, Braxton E, Hobbs J, Quigley MR. Chronic subdural hematoma in the elderly: not a benign disease: clinical article. Journal of neurosurgery. 2011;114(1):72-6.

• Kolias AG, Chari A, Santarius T, et al. Chronic subdural haematoma: modern management and emerging therapies. Nat Rev Neurol 2014;10(10):570–8.

• Adhiyaman V, Asghar M, Ganeshram KN, et al. Chronic subdural haematoma in the elderly. Postgrad Med J 2002;78(916):71–5.

• Mori K, Maeda M. Surgical treatment of chronic subdural hematoma in 500 consecutive cases: clinical characteristics, surgical outcome, complications, and recurrence rate. Neurol Med Chir (Tokyo) 2001;41(8):371–81.

• Gelabert-Gonza´lez M, Iglesias-Pais M, Garcı´a-Allut A, et al. Chronic subdural haematoma: surgical treatment and outcome in 1000 cases. Clin Neurol Neurosurg 2005;107(3):223–9.

• Ivamoto HS, Lemos HP, Atallah AN. Surgical treatments for chronic subdural hematomas: a comprehensive systematic review. World Neurosurg 2016; 86:399–418.

• Iliescu IA, Constantinescu AI. Clinical evolutional aspects of chronic subdural haematomas - literature review. J Med Life 2015;8(Spec Issue):26–33.

• Sambasivan M. An overview of chronic subdural hematoma: experience with 2300 cases. Surg Neurol 1997;47(5):418–22.