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Ischemic Symptoms (ischemic + symptom)
Selected AbstractsExtracranial and intracranial vertebral artery dissection: Long-term clinical and duplex sonographic follow-upJOURNAL OF CLINICAL ULTRASOUND, Issue 8 2008Tiemo Wessels MD Abstract Purpose. To determine the value of color Doppler sonography (CDUS) in the diagnosis and follow-up of patients with extracranial and intracranial vertebral artery (VA) dissection. Method. Thirty-three patients aged 42 ± 12 years with 40 VADS confirmed via digital subtraction angiography (DSA) (n = 37) and magnetic resonance angiography (MRA) (n = 3) were included in the study. All patients were investigated with extracranial CDUS and transcranial CDUS (TCCDUS) over a mean ± SD follow-up period of 42 ± 24 months and occurrence of new ischemic symptoms was assessed. Sonographic results were compared with initial and follow-up angiographic results. Results. At presentation, 24/33 (73%) patients had suffered an ischemic stroke, 5/33 (15%) had a transient ischemic attack (TIA), and 4/33 (12%) were asymptomatic. Two patients had a recurrent vertebrobasilar TIA; there was no recurrent stroke. The initial DSA findings consisted of 14 stenoses, 20 tapered occlusions, and 6 pseudoaneurysms. During follow-up, 63% of the vessels recanalized. Sonographic findings were consistent with angiographic findings in 80% at the initial examination and in 86% during follow-up. The main reason for discordant results was the failure of CDUS to detect pseudoaneurysms. No recurrence occurred in the vertebral arteries (VA), but 1 patient had an asymptomatic carotid artery dissection during follow-up. Conclusion. Recurrent TIA or stroke after VAD appears to be extremely rare, independent of recanalization or persistent occlusion of the affected artery. CDUS and TCCDUS provide reliable follow-up of VAD in all patients presenting with stenosis or occlusion, but do not allow for detection of pseudoaneurysms of the VA. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2008 [source] Fourier transformation of arterial Doppler waveforms of the lower extremityJOURNAL OF CLINICAL ULTRASOUND, Issue 6 2004Hong Gi Lee MD Abstract Purpose Although it is well known that the normal, triphasic pulsatile arterial Doppler waveform changes in shape as flow is impaired, interpretation of the waveform has largely been subjective. We aimed to describe the Doppler waveforms of the lower extremity objectively using Fourier transformation. Methods Sixty-eight zero-crossing detector arterial recordings from 25 lower extremities were grouped as follows: group 1, no ischemic symptoms with an ankle-brachial index (ABI) > 0.9 (n = 17, 8 limbs); group 2, no ischemic symptoms with ABI < 0.9 (n = 18, 5 limbs); group 3, symptoms of claudication (n = 19, 7 limbs); group 4, rest pain or tissue loss (n = 14, 5 limbs). The waveforms were Fourier transformed and their amplitudes and phases were compared up to the third harmonic (H3). Results Amplitudes of both the fundamental (H1) and second harmonic (H2) were predominant in group 1. In contrast, amplitudes of the H2 and H3 decreased with altered flow (p < 0.0001 for group 1 versus others). The phases of the H1 and H2 were delayed with altered flow (p < 0.05 for group 1 versus others). Phases of the H1 were different between group 2 and 4 (p < 0.05). The difference of phase between the H3 and H1 was shortened with altered flow (p < 0.05 for group 1 or 2 versus group 4). Multivariate analysis revealed that the relative amplitudes of the H2 and H3, the phases of the H1 and H2, and the relative phase of the H3 were significant discriminators among the groups. Conclusion Abnormal waveforms could be characterized by the predominant amplitude of the H1, phase delay of the H1 and H2, and shortening of the relative phase of the H3. These parameters may be useful in the evaluation of Doppler waveforms in patients with peripheral arterial disease. © 2004 Wiley Periodicals, Inc. J Clin Ultrasound 32:277,285, 2004 [source] Microemboli in Aneurysmal Subarachnoid HemorrhageJOURNAL OF NEUROIMAGING, Issue 4 2008Jose G. Romano MD ABSTRACT BACKGROUND AND PURPOSE The determinants of ischemic complications in subarachnoid hemorrhage (SAH) are not well defined. The objective of this study is to evaluate the role of microemboli in SAH-related cerebral ischemia. METHODS Forty patients with aneurysmal SAH were monitored with transcranial Doppler (TCD) for the presence of embolic signals (ES) and vasospasm, and followed clinically for the development of cerebral ischemic symptoms, from the time the aneurysm was secured until day 14 posthemorrhage or discharge. RESULTS Microembolic signals were detected in 15/40 patients, appeared at a mean of 6.7 days after hemorrhage, and were often noted bilaterally. There was a close association between ES and cerebral ischemic symptoms (P= .003), and ES were commonly present in the distribution of the vessel with ischemic symptoms. Ultrasonographic vasospasm did not correlate with ischemia and there was no relationship between microembolic signals and vasospasm. CONCLUSIONS In this study, ES detected in over a third of SAH victims, were associated with the development of cerebral ischemic symptoms, and were not related to vasospasm, but rather appeared to be an independent risk factor for the development of ischemic symptoms in SAH. [source] Intracranial atherosclerotic disease: An update,ANNALS OF NEUROLOGY, Issue 6 2009Adnan I. Qureshi MD The consensus conference on intracranial atherosclerosis provides a comprehensive review of the existing literature relevant to the epidemiology, diagnosis, prevention, and treatment of intracranial atherosclerosis, and identifies principles of management and research priorities. Patients who have suffered a stroke or transient ischemic attack attributed to stenosis (50,99%) of a major intracranial artery face a 12 to 14% risk for subsequent stroke during the 2-year period after the initial ischemic event, despite treatment with antithrombotic medications. The annual risk for subsequent stroke may exceed 20% in high-risk groups. In patients with intracranial atherosclerotic disease, short-term and long-term anticoagulation is not superior to antiplatelet treatment. Overall, the subgroup analyses from randomized trials provide evidence about benefit of aggressive atherogenic risk factor management. Intracranial angioplasty with or without stent placement has evolved as a therapeutic option for patients with symptomatic intracranial atherosclerotic disease, particularly those with high-grade stenosis with recurrent ischemic symptoms, medication failure, or both. A multicenter randomized trial is currently under way to compare stent placement with intense medical management for patients with high-grade symptomatic intracranial atherosclerotic disease. Ann Neurol 2009;66:730,738 [source] | ||||||||||