Spontaneous Subdural Hematoma

Most acute SDH are due to trauma from laceration of bridging veins in the subdural space.  Nontraumatic cases are rare (incidence rate 3-5%) and predominantly affects adulst in 5th to 7th decade.


Predispoding factors to spontaneous SDH:

  1. vascular abnormalities – cerebral aneurysm, AVM, dural AVF
  2. hematological disorders
  3. anticoagulant therapy


Mechanisms of nontraumatic SDH:

  1. aneurysms:
    1. previous minor hemorrhages fixes an aneursym to local arachnoid adhesions –> results in bleeding directly into subdural space when arachnoid tear occurs after aneurysm rupture
    2. hemorrhage under high pressure leading to pia arachnoid rupture and extravasation into subdural space
  2. sudden increase in intravenous pressure (Valsalva) – rupture of bridging dural veins
  3. intracranial hypotension – systemic vascular hypotension after exercise



  • Modality of choice:  CT;  cerebral angio to exclude vascular abnormalities
  • Other investigations:  coagulation tests




Wang, Hui Sun, Seok Won Kim, and Sung Hoon Kim. “Spontaneous Chronic Subdural Hematoma In An Adolescent Girl”. J Korean Neurosurg Soc 53.3 (2013): 201. Web.


Tagged: , , , ,

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: