Transcranial Doppler and Cerebral Augmentation in Acute Ischemic Stroke.

From the Division of Neurology, Department of Medicine (MS, MI, KB, KK, DM, CD, BS, AS); Department of Radiology, University of Alberta, Edmonton, AB, Canada (DE).
Journal of neuroimaging: official journal of the American Society of Neuroimaging (Impact Factor: 3.36). 01/2012; DOI: 10.1111/j.1552-6569.2011.00674.x
Source: PubMed

ABSTRACT BACKGROUND: Collateral flow augmentation using partial aortic occlusion may improve cerebral perfusion in acute stroke. We assessed the effect of partial aortic occlusion on arterial flow velocities of acute stroke patients. METHODS: Patients with neurological deficits following thrombolysis were treated with partial aortic occlusion. Transcranial Doppler ultrasound (TCD) was used to measure arterial flow velocities at baseline, before and during balloon inflation. The augmented mean flow velocity (MFV), peak systolic velocity (PSV), and end diastolic velocity flow percentages (aMFV%, aPSV%, aEDV%) were calculated and compared based on outcome. RESULTS: Of 11 patients, 3 did not have a temporal window and thus were excluded from our analysis. Six of the remaining 8 patients had middle cerebral artery (MCA) occlusions; the final 2 had terminal internal carotid artery (TICA) occlusions. Three of these 8 patients had good outcome at 90 days (mRS < 3). Before intra-aortic balloon inflation (IABI), the mean affected artery MFV was 23 ± 11 cm/s; during the procedure it was 26 ± 12 cm/s (P = .2). Mean affected artery PSV at baseline and during balloon inflation were 37 ± 16 and 46 ± 23, respectively (P = .1). Mean augmented affected artery MFV% in patients with good long-term outcome was 65.4 ± 46, while the result in those with poor outcome was -3.7 ± 21 (P = .03). Three patients developed anterior cross-filling, and of these 2 had good long-term outcome. CONCLUSION: TCD monitoring of patients treated with IABI may help in predicting outcome in this novel device. J Neuroimaging 2012;XX:1-6.

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