Detecting traumatic internal carotid artery dissection using transcranial Doppler in head-injured patients

The early diagnosis of traumatic internal carotid artery dissection (TICAD) is essential for initiating appropriate treatment and improving outcome. We searched for criteria from transcranial Doppler (TCD) measurements on admission that could be associated with subsequent TICAD diagnosis in patients with traumatic brain injury (TBI).

We conducted a retrospective 1:4 matched (age, mean arterial blood pressure) cohort study of 11 TBI patients with TICAD and absent or mild brain lesions on initial CT scan, 22 TBI controls with comparable brain CT scan lesions (controls 1), and 22 TBI controls with more severe brain CT scan lesions (controls 2) on admission. TCD measurements were obtained on admission from both middle cerebral arteries (MCA). All patients had subsequent CT angiography to diagnose TICAD.

A >25% asymmetry in the systolic blood flow velocity between the two MCA was found in 9/11 patients with TICAD versus 0/22 in controls 1 and 5/22 in controls 2 (p < 0.01). The combination of this asymmetry with an ipsilateral pulsatility index < or =0.80 was found in 9/11 patients with TICAD versus none in the two groups of controls (p < 0.01).

Our results suggest that significant asymmetry in the systolic blood flow velocity between the MCAs and a reduced ipsilateral pulsatility index could be criteria from TCD measurements associated with the occurrence of TICAD in head-injured patients. If prospectively validated, these findings could be incorporated in screening protocols for TICAD in patients with TBI.