Detection of reversed basilar flow with power-motion Doppler after acute occlusion predicts favorable outcome.

BACKGROUND AND PURPOSE

Power-motion transcranial Doppler PMD-TCD is a new method for simultaneous display of flow at multiple depths. We aimed to determine clinical significance of PMD-TCD demonstration of reversed basilar flow in patients with basilar artery (BA) occlusion.

METHODS

We prospectively evaluated patients with acute vertebrobasilar ischemia using PMD-TCD. Using a predefined set of TCD depth criteria and specific flow findings, occlusion was localized to the proximal, middle, or distal BA stem. The National Institutes of Health Stroke Scale was used to measure stroke severity and the modified Rankin Scale (mRS) to assess outcome at 3 months.

RESULTS

BA occlusion was diagnosed in 16 patients (3 women, mean age 65, median NIHSS 8, mean time from symptoms onset 8.5 hours). PMD-TCD diagnosis of BA occlusion was confirmed in 11 of 12 patients who underwent invasive angiography. Reversed BA flow on PMD-TCD was identified in 8 patients (50%). Angiography confirmed flow from carotid system in 6 of these 8 patients (kappa=0.87). Patients with reversed BA flow showed lower NIHSS scores on admission (median 4 versus 15.5, P=0.009), on discharge (2 versus 21.5, P=0.03) and did not experience neurological deterioration during hospital stay (n=0 versus 4, P=0.05). There was a trend toward better outcome at 3 months (mRS 1 versus 4, P=0.07).

CONCLUSIONS

Detection of reversed flow in the distal BA with PMD-TCD is associated with lower stroke severity and better outcome after acute basilar artery occlusion.