Carotid Endarterectomy Improves Cerebrovascular Reserve Capacity Preferentially in Patients with Preoperative Impairment as Indicated by Asymmetric BOLD Response to Hypercapnia

Article (PDF Available)inEuropean journal of vascular and endovascular surgery: the official journal of the European Society for Vascular Surgery 38(5):546-51 · October 2009with54 Reads
DOI: 10.1016/j.ejvs.2009.06.010 · Source: PubMed
Abstract
In patients with symptomatic carotid artery disease the predominant mechanism causing ischaemic injury is considered to be thromboembolic, however compromise of cerebral haemodynamics is considered to be a significant factor. Removal of the embolic source is accepted as the major benefit from Carotid Endarterectomy (CEA), however improvement in cerebral haemodynamics may be another beneficial outcome as suggested by Transcranial doppler (TCD). Blood Oxygen Level-Dependent (BOLD) hypercapnia functional Magnetic Resonance imaging (fMRI) can be used to map the Cerebrovascular Reserve (CVR). The aim of this study was to assess the effects of carotid surgery on cerebral haemodynamics in patients with carotid artery disease using a hypercapnia BOLD fMRI and assessment of hemispheric asymmetry.

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    • "In patients with tight intracranial arterial stenosis, this imaging may identify patients at risk of a failure of a well carried out medical treatment and help better select patients likely to benefit from endovascular treatment (Figs. 3 and 4) [198]. The imaging of cerebral vasoreactivity shows an improvement , or even normalization, of the vascular reserve after the surgical treatment of a carotid stenosis [197,220,221], moyamoya disease [195,222—226] or tight intracranial arterial stenosis (Fig. 4). "
    [Show abstract] [Hide abstract] ABSTRACT: The functional imaging of perfusion enables the study of its properties such as the vasoreactivity to circulating gases, the autoregulation and the neurovascular coupling. Downstream from arterial stenosis, this imaging can estimate the vascular reserve and the risk of ischemia in order to adapt the therapeutic strategy. This method reveals the hemodynamic disorders in patients suffering from Alzheimer's disease or with arteriovenous malformations revealed by epilepsy. Functional MRI of the vasoreactivity also helps to better interpret the functional MRI activation in practice and in clinical research.
    Article · Sep 2013
    • "To prevent ischemic stroke, patients with severe carotid stenosis often benefit from interventions, such as carotid endarterectomy (CEA) and carotid angioplasty with stent Radiology Research and Practice 5 placement (CAS)727374. Recently, studies have reported that patients with carotid stenosis, who showed impaired CVR before carotid intervention, had great CVR improvement after CEA or CAS [5, 6]. This finding is probably due to an improvement in vasodilatory ability, indicating return of vascular reserve capacity. "
    Full-text · Dataset · Aug 2012 · Diagnostic and interventional imaging
    • "To prevent ischemic stroke, patients with severe carotid stenosis often benefit from interventions, such as carotid endarterectomy (CEA) and carotid angioplasty with stent Radiology Research and Practice 5 placement (CAS)727374. Recently, studies have reported that patients with carotid stenosis, who showed impaired CVR before carotid intervention, had great CVR improvement after CEA or CAS [5, 6]. This finding is probably due to an improvement in vasodilatory ability, indicating return of vascular reserve capacity. "
    [Show abstract] [Hide abstract] ABSTRACT: Impaired cerebrovascular reactivity (CVR), a predictive factor of imminent stroke, has been shown to be associated with carotid steno-occlusive disease. Magnetic resonance imaging (MRI) techniques, such as blood oxygenation level-dependent (BOLD) and arterial spin labeling (ASL), have emerged as promising noninvasive tools to evaluate altered CVR with whole-brain coverage, when combined with a vasoactive stimulus, such as respiratory task or injection of acetazolamide. Under normal cerebrovascular conditions, CVR has been shown to be globally and homogenously distributed between hemispheres, but with differences among cerebral regions. Such differences can be explained by anatomical specificities and different biochemical mechanisms responsible for vascular regulation. In patients with carotid steno-occlusive disease, studies have shown that MRI techniques can detect impaired CVR in brain tissue supplied by the affected artery. Moreover, resulting CVR estimations have been well correlated to those obtained with more established techniques, indicating that BOLD and ASL are robust and reliable methods to assess CVR in patients with cerebrovascular diseases. Therefore, the present paper aims to review recent studies which use BOLD and ASL to evaluate CVR, in healthy individuals and in patients with carotid steno-occlusive disease, providing a source of information regarding the obtained results and the methodological difficulties.
    Full-text · Article · Jun 2012
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