Traumatic subarachnoid hemorrhage pathology

Traumatic subarachnoid hemorrhage is most commonly seen in the cerebral sulci than in the Sylvian fissure and basal cisterns ¹⁾

When in the basal cisterns, it has an affinity for the quadrigeminal cistern and ambient cistern ²⁾, tSAH is also commonly seen adjacent to skull fractures and cerebral contusions ³⁾

The exact mechanism of tSAH remains uncertain although it is clear that a number of etiologies exist and these will determine, at least to a degree, the distribution of blood. Causes of tSAH include ⁴⁾:

direct extravasation of blood from an adjacent cerebral contusion

arterial dissection

direct damage to small veins or arteries

sudden increase in intravascular pressures leading to rupture