Acute Subdural Hematoma
Last Updated: October 1, 2018
In contrast with a treatable epidural hematoma (EDH), an acute subdural hematoma (ASDH) carries a high risk of morbidity and mortality, even with timely decompression.
The difference in outcome between EDH and ASDH arises from two discrete but related etiologies. First, the force of trauma or impact necessary to cause an ASDH is significantly greater than that required for an EDH. The typical scenario for an ASDH involves an acceleration-deceleration shear injury (e.g., a motor vehicle accident, fall, or whiplash injury) during which the brain’s inertia continues to move the brain after the body and skull have stopped moving. This phenomenon results in significant shear vectors affecting the brain parenchyma and its tethered and vulnerable venous system. Diffuse axonal injury is common among patients suffering from ASDH.
Second, with ASDH, there is an increased likelihood of injury to the underlying brain parenchyma. Thus, the ASDH has two potential sources of hematoma formation: the brain parenchyma and the parasagittal bridging veins. A laceration of the brain resulting in an expandi...