Cerebral Vasospasm in Traumatic Brain Injury

Table 1

Comparison of the epidemiology of traumatic subarachnoid hemorrhage (tSAH) to that of aneurysmal subarachnoid hemorrhage (aSAH). The shorter duration and lower incidence of clinical vasospasm highlight the less severe course of vasospasm following tSAH in comparison to aSAH.

	tSAH	aSAH
Earliest onset (PBD*)	2 [9, 10, 27–30]	3 [8, 26]
Timing of peak vessel-velocity (PBD*)	5–7 [19, 27]	5–14 [19]
Incidence of TCD^†-diagnosed vasospasm	19%–68% [8, 27, 28, 30, 32, 33]	38%–45% [34–36]
Incidence of angiography-diagnosed vasospasm	18.6%–41% [37, 38]	43.2% [34]
Evidence of clinical vasospasm among those with radiographic vasospasm	3.9%–16.6% [8, 11, 30, 39]	17%–40% [26]

∗PBD: postbleed day. †TCD: transcranial Doppler.