In patients with acute ischemic stroke, continuous transcranial Doppler augments t-PA-induced arterial recanalization, with a nonsignificant trend toward an increased rate of recovery from stroke, as compared with placebo.

Background and Purpose-The objective of this study was to examine clinical outcomes and recanalization rates in a multicenter cohort of stroke patients receiving intravenous tissue plasminogen activator by site of occlusion localized with bedside transcranial Doppler. Angiographic studies with intraarterial thrombolysis suggest more proximal occlusions carry greater thrombus burden and benefit less from local therapy. Methods-Using validated transcranial Doppler criteria for specific arterial occlusion (Thrombolysis in Brain Ischemia flow grades), we compared the rate of dramatic recovery (National Institutes of Health Stroke Scale score Յ2 at 24 hours) and favorable outcomes at 3 months (modified Rankin Scale Յ1) for each occlusion site. We determined the likelihood of recanalization at various occlusion sites and its predictors. Then, stepwise logistic regression was used to determine predictors of complete recanalization. Results-Three hundred thirty-five patients had a mean age 69Ϯ13 years and 48.5% were women (median baseline National

A B S T R A C T INTRODUCTIONTranscranial Doppler (TCD) is a physiological ultrasound test with established safety and efficacy. Although imaging devices may be used to depict intracranial flow superimposed on structural visualization, the end-result provided by imaging duplex or nonimaging TCD is sampling physiological flow variables through the spectral waveform assessment. SUMMARY OF RESULTS Clinical indications considered by this multidisciplinary panel of experts as established are: sickle cell disease, cerebral ischemia, detection of right-to-left shunts (RLS), subarachnoid hemorrhage, brain death, and periprocedural or surgical monitoring. The following TCD-procedures are performed in routine in-and outpatient clinical practice: complete or partial TCD-examination to detect normal, stenosed, or occluded intracranial vessels, collaterals to locate an arterial obstruction and refine carotid-duplex or noninvasive angiographic findings; vasomotor reactivity testing to identify high-risk patients for first-ever or recurrent stroke; emboli detection to detect, localize, and quantify cerebral embolization in real time; RLS-detection in patients with suspected paradoxical embolism or those considered for shunt closure; monitoring of thrombolysis to facilitate recanalization and detect reocclusion; monitoring of endovascular stenting, carotid endarterectomy, and cardiac surgery to detect perioperative embolism, thrombosis, hypo-and hyperperfusion. CONCLUSIONBy defining the scope of practice, these standards will assist referring and reporting physicians and third parties involved in the process of requesting, evaluating, and acting upon TCD results.

Acute ischemic stroke patients may benefit from lower head-of-the-bed positions to promote residual blood flow to ischemic brain tissue.

In our experience, surgical repair of acute type A aortic dissection can be performed in the setting of preoperative stroke with acceptable mortality. Moreover, no worsening of neurologic condition was observed after surgical repair. Immediate surgical repair is warranted even if acute type A aortic dissection is complicated by stroke.

Patients and MethodsThis is a retrospective analysis of the CLOTBUST collaboration databank that includes patients with acute MCA occlusions treated with intravenous tissue plasminogen activator (tPA). 3 A sonographer performed transcranial Doppler (TCD) with a 2-MHz device (Ez-Dop, DWL; PMD 100, Spencer Technologies; Multigon, 500 mol/L, Multigon Industries). MCA occlusion and recanalization were identified using previously validated criteria before and during the first 2 hours after tPA bolus. 3 Before tPA bolus, we also performed carotid duplex (Sonosite 180 Plus), and previously validated diagnostic criteria for ICA occlusion were applied. 4 Tandem ICA/MCA lesions (tandem group) were defined as hemodynamically significant ICA obstruction (70% to 100% obstruction) with MCA occlusion, and isolated MCA occlusion was diagnosed when patients had abnormal TIBI (Thrombolysis In Brain Ischemia) flow grades without evidence of significant ICA obstruction on carotid duplex ultrasound and TCD.Neurological deficit was measured with the National Institutes of Health Stroke Scale (NIHSS) before, 30, 60, 90, and 120 minutes, and 24 hours after bolus. Modified Rankin scale (mRS) scores were obtained at 90 days after onset by a stroke neurologist blind to TCD findings. Early neurological improvement (ENI) was defined as reduction of NIHSS by Ն10 or decrease of total NIHSS to Յ4 within 24 hours after bolus. 5 Good outcome was defined by mRS Յ2. ResultsA total of 104 patients were included in our study. Seventytwo (69%) patients had isolated MCA occlusion and 32 (31%) patients had tandem lesions. Their demographic data and clinical parameters are summarized in the Table. Stroke subtypes in the isolated MCA group were: LVA 8.5%; CE 5.3%; LA 1%; and UE 37% of patients. In patients with tandem lesion, stroke subtypes were: LVA 62%; CE 22%; OE 6%; and UE 9% of patients.Complete recanalization rate increased with time after bolus in the isolated lesion group. It occurred in 26.4% of the isolated lesion group and 9.4% of the tandem group at 90 minutes after bolus (Pϭ0.05) and at 2 hours in 38.9% and 9.4%, respectively (Pϭ0.002; Figure 1). Complete recanalization rate was different according to the stroke subtype: LVA 14.4% and CE 39.1% (Pϭ0.02).ENI was achieved in 46% of the isolated lesion group and in 25% of the tandem group (Pϭ0.045; Table), and the median NIHSS score reduction was different between the 2 groups at 2 hours and 24 hours after bolus (Pϭ0.002 and Pϭ0.05, respectively; Figure 2). Good outcomes were similar in the 2 groups. DiscussionOur results showed that early complete recanalization and ENI are more common with the isolated lesion group compared with the tandem group despite similar baseline characteristics. MCA recanalization rate was lower with tandem than with isolated lesions in other studies at Ͼ24 hours after onset. 2,7 In our study, the isolated lesion group had faster and higher complete recanalization rate than the tandem group during the first 2 hours. Recanalization rate increased with time in the iso...

Background-Multiple lines of evidence suggest cardiovascular co-morbidities hasten the onset of Alzheimer's disease (AD) or accelerate its course.Methods-To evaluate the utility of cerebral vascular physical function/condition parameters as potential systemic indicators of AD, we employed transcranial Doppler (TCD) ultrasound to assess cerebral blood flow and vascular resistance of the 16 arterial segments comprising the circle of Willis and its major tributaries.Results-Our study revealed decreased arterial mean flow velocity (MFV) and increased pulsatility index (PI) are associated with a clinical diagnosis of presumptive AD. Cerebral blood flow impairment revealed by these parameters reflects the global hemodynamic and structural consequences of a multifaceted disease process yielding diffuse congestive microvascular pathology, increased arterial rigidity, and decreased arterial compliance combined with putative age-associated cardiovascular output declines.

Background and Purpose-We routinely perform an urgent bedside neurovascular ultrasound examination (NVUE) with carotid/vertebral duplex and transcranial Doppler (TCD) in patients with acute cerebral ischemia. We aimed to determine the yield and accuracy of NVUE to identify lesions amenable for interventional treatment (LAITs). Methods-NVUE was performed with portable carotid duplex and TCD using standardized fast-track (Ͻ15 minutes) insonation protocols. Digital subtraction angiography (DSA) was the gold standard for identifying LAIT. These lesions were defined as proximal intra-or extracranial occlusions, near-occlusions, Ն50% stenoses or thrombus in the symptomatic artery.