Potential Value of Poststroke Extracranial Arterial Blood Flow Volume in the Prediction of Stroke Functional Outcome

Abstract

Background and Purpose: Cerebral vasoreactivity and collateral circulation are important protective mechanisms against cerebral ischemia. Previous studies suggest that the efficiency of these mechanisms can be reflected by extracranial arterial blood flow volume. Brain damage leading to neurological impairments can influence patients’ functional recovery after stroke. This study attempted to explore the potential value of poststroke extracranial arterial blood flow volume in the prediction of stroke patients’ functional outcome. Methods: We prospectively studied 362 consecutive patients who were hospitalized for recent acute strokes. All patients underwent extracranial arterial blood flow volume measurement of the carotid and vertebral arteries by color velocity imaging quantification within 3 days after admission. Their functional recovery was assessed 6 months after stroke. The effect of poststroke extracranial arterial blood flow volume on patients’ functional outcome was tested by multivariate ordinal regression after controlling for other independent variables. Significance was at p < 0.05. Results: Poststroke extracranial arterial blood flow volume together with age, prestroke modified Rankin scale, the National Institutes of Health Stroke Scale and diabetes mellitus had significant effects on the patients’ 6-month functional outcome as measured by the modified Rankin scale after controlling for other independent variables (p < 0.05). Conclusions: Poststroke extracranial arterial blood flow volume is an independent outcome predictor. The graded predictive power of this parameter is potentially more superior than other outcome predictors by allowing classification of stroke outcome according to the degree of severity. A large prospective study is thus warranted to investigate its clinical value in the management of stroke patients.

Compensatory patterns of collateral flow in stroke patients with unilateral and bilateral carotid stenosis

“…The assessment of carotid stenosis and measurement of BFV was performed as described previously [ 8 , 9 , 11 , 12 ]. A 7.5-MHz linear transducer of a Philips SD800 ultrasound unit (Best, the Netherlands) which has a standard feature of duplex Doppler imaging as well as a color velocity imaging quantification (CVIQ) software for blood flow volume measurement was used.…”

“…Color velocity imaging quantification (CVIQ) ultrasound has been proved to be a noninvasive technique that can reveal extracranial arterial blood flow volume, which is an indicator of cerebral perfusion [ 8 – 12 ]. Our previous studies demonstrated that poststroke extracranial arterial blood flow volume estimated by CVIQ is an independent predictor of functional outcome and recurrent stroke [ 11 , 12 ]. In addition, it is important to assess the contribution of the contralateral ICA, the ipsilateral ECA, and the vertebral arteries to the collateral pathways in patients with symptomatic ICA stenosis [ 13 – 15 ].…”

Total Cerebral Blood Flow Estimated by Color Velocity Imaging Quantification Ultrasound: A Predictor for Recurrent Stroke?

“…Moreover, it is comparable to magnetic resonance angiography with phase contrast flow quantification (Ho et al, 2002a). Our recent study also found that post-stroke extracranial arterial blood flow volume is an independent predictor of functional outcome (Ho et al, 2005b). However, this methodology has shortcomings.…”

Is Counterpulsation a Potential Therapy for Ischemic Stroke?

“…Ischemic stroke occurs when there is a lack of blood flow to the brain. Abundant evidence shows that poor cerebral perfusion is related to unfavorable functional outcome, further strokes and other vascular events [1,2,3,4]. Although a number of major clinical studies have demonstrated the benefit of plaque stabilization [5, 6] and antithrombotic therapy [7, 8], these medications are mainly for secondary stroke prevention.…”