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ICA Stenosis (ica + stenosis)
Selected AbstractsCarotid sonography and transesophageal echocardiography in patients with ischemic stroke or transient ischemic attack in the territory of the carotid arteryJOURNAL OF CLINICAL ULTRASOUND, Issue 8 2006Marjatta Strandberg MD Abstract Purpose. To assess the benefit of combining carotid sonography and transesophageal echocardiography (TEE) for the evaluation of patients with stroke or transient ischemic attack (TIA) in the territory of the carotid artery. Methods. During a 2-year period in Turku University Hospital, consecutive in patients with stroke or TIA who were candidates for carotid endarterectomy and for oral anticoagulation were evaluated with carotid sonography for symptomatic moderate (50,69%) or severe (,70%) internal carotid artery (ICA) stenosis, and with TEE for potential cardiac sources of embolism. Results. In 20% (40/197) of patients, a severe symptomatic ICA stenosis and/or a major risk factor for a cardiac source of embolism were found. In 56% (110/197) of patients, a moderate or severe symptomatic ICA stenosis and/or a potential cardiac source of embolism were found, whereas 11% (21/197) of patients had both a moderate or severe symptomatic ICA stenosis and a potential cardiac source of embolism. Conclusions. This study suggests that the presence of a moderate or severe symptomatic ICA stenosis does not exclude the presence of a potential cardiac source of embolism and vice versa. Carotid sonography and TEE complement each other and are valuable diagnostic tools that should be recommended in patients with ischemic stroke or TIA in the territory of the carotid artery when they are candidates for carotid endarterectomy and for oral anticoagulation. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:374,379, 2006 [source] Ophthalmic Artery Flow Direction on Color Flow Duplex Imaging Is Highly Specific for Severe Carotid StenosisJOURNAL OF NEUROIMAGING, Issue 1 2002Patrick S. Reynolds MD Background/Purpose. Collateral flow patterns are important risk factors for brain ischemia in the presence of internal carotid artery (ICA) stenosis or occlusion. Ophthalmic artery (OA) flow reversal, routinely studied by transcranial Doppler sonography, is an important marker for high-grade ICA stenosis or occlusion. The authors sought to define the value of assessing OA flow direction with color flow duplex ultrasonography (CDUS) in the setting of significant ICA disease. Methods. Of all patients having routine carotid ultrasound in the neurosonology laboratory between July 1995 and November 2000, 152 had both carotid and orbital (OA flow direction by reduced power orbital CDUS) examinations as well as angiographic confirmation of stenosis to which North American Symptomatic Carotid Endarterectomy Trial criteria could be applied. Degree of angiographic stenosis in these 152 patients (304 arteries) was correlated with OA flow direction. Results. Of 304 arteries, 101 had greater than 80% stenosis by angiogram. In 56 of these 101 arteries with high-grade stenosis or occlusion, the ipsilateral OA was reversed; however, OA flow direction was never reversed ipsilateral to arteries with less than 80% stenosis (sensitivity 55%, specificity 100%, negative predictive value 82%, and positive predictive value 100% for OA flow reversal as a marker of high-grade carotid lesions). Discussion/Conclusions. OA flow direction is easily studied with CDUS. Reversed OA flow direction is highly specific (100%) for severe ipsilateral ICA stenosis or occlusion, with excellent positive predictive value, moderate negative predictive value, and limited sensitivity. OA flow reversal is not only quite specific for severe ICA disease, which may be helpful if the carotid CDUS is difficult or inadequate, but may also provide additional hemodynamic insights (ie, the inadequacy of other collateral channels such as the anterior communicating artery). OA evaluation can provide important hemodynamic information and should be included as part of carotid CDUS if there is any evidence of ICA stenosis or occlusion. [source] Screening for Intracranial Stenosis With Transcranial Doppler: The Accuracy of Mean Flow Velocity ThresholdsJOURNAL OF NEUROIMAGING, Issue 1 2002Robert A. Felberg MD ABSTRACT Background. Patients with 50% intracranial arterial stenosis may require more intensive therapies for stroke prevention. Transcranial Doppler (TCD) is a convenient noninvasive screen for intracranial stenosis. The accuracy of different mean flow velocity (MFV) thresholds for determining the degree of stenosis remains uncertain. Methods. The authors prospectively compared the accuracy of TCD criteria and MFV thresholds to magnetic resonance, computed tomography, and digital subtraction angiography in patients with symptoms of recent or remote stroke or transient ischemic attack. Stenosis on angiography was measured as 0%, <50%, or ,50% diameter reduction. Results. Of 136 consecutive patients, 33 (24%) had distal internal carotid artery (ICA), middle cerebral artery (MCA), posterior cerebral artery, or basilar artery stenosis on angiography (14 patients [10%] were excluded due to incomplete TCD examinations, mainly from a lack of temporal windows). TCD showed 31 true-positive, 9 false-positive, 2 false-negative, and 94 true-negative studies. For all vessels, TCD had a sensitivity of 93.9% (confidence interval [CI] = 89%-98%), a specificity of 91.2% (CI = 87%-96%), a positive predictive value (PPV) of 77.5%, and a negative predictive value (NPV) of 97.9%. The trade-off in sensitivity and specificity for MCA MFV thresholds was as follows: MFV ,80 cm/s had a sensitivity of 100%, a specificity of 96.9% (CI = 94%-99%), a PPV of 84%, and an NPV of 100%. MFV,100 cm/s had a sensitivity of 100%, a specificity of 97.9% (CI = 96%-99%), a PPV of 88.8%, and an NPV of 94.9%. MFV,120 cm/s had a sensitivity of 68.7% (CI = 61%-78%), a specificity of 100%, a PPV of 100%, and an NPV of 94.9%. Reasons for false-positive findings include collateralization of flow in the presence of proximal ICA stenosis and prestenotic to stenotic MCA velocity ratios of 1:,2. Conclusion. TCD is both sensitive and specific in identifying ,50% intracranial arterial stenosis. A MFV threshold cutoff of 100 cm/s has an optimal sensitivity and specificity trade-off for ,50% MCA stenosis. To help avoid false-positive results, a prestenotic to stenotic MCA velocity ratio of 1:,2 should be used in addition to the MFV threshold. [source] The effect of statin therapy on the progression of carotid artery stenosis in relation to stenosis severityACTA NEUROLOGICA SCANDINAVICA, Issue 1 2010O. Hegland Objectives,,, To examine the effect of early statin treatment on progression of arteriosclerosis in internal carotid arteries (ICA); to compare the progression of arteriosclerosis in ICA of patients treated with a statin to the progression seen in drug-naïve patients. Patients and methods,,, We performed repetitive Doppler scans of 363 carotid arteries with ICA stenosis ,40% in 254 patients over time. Information on statin therapy and other risk factors for stroke were correlated with the annual change in degree of ICA stenosis. Results,,, In statin-treated patients, 19% of ICA stenosis showed a progression while 74% showed a regression of stenosis. In statin - naïve patients, 63% of stenotic arteries showed a progression, while a reduction could be observed in 28%. Decrease of ICA stenosis was most accentuated in patients with a mild stenosis and was independent of serum cholesterol levels. Conclusion,,, Treatment with statins already in early stages of ICA stenosis might delay the progression and even reverse the degree of stenosis. [source] Association between intraplaque haemorrhage in the carotid atherosclerotic lesion, the degree of internal carotid artery stenosis and timing of ischaemic neurological eventsBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 4 2001R. Mofidi Background: Expansion of carotid atherosclerotic plaques as a result of intraplaque haemorrhage has been implicated in the development of ischaemic neurological events. The relationship between the quantity of haemorrhage in the dominant atherosclerotic lesion, the degree of internal carotid artery (ICA) stenosis and the chronology of patients' symptoms was examined. Methods: Consecutive patients undergoing carotid endarterectomy were included. The nature and timing of symptoms were recorded. Aortic arch injection digital subtraction angiography was performed before operation. Carotid endarterectomy specimens were serially sectioned and examined histologically. The amount of intraplaque haemorrhage was measured with digital image analysis. The influence of timing of symptoms on the quantity of intraplaque haemorrhage was compared with Kaplan,Meier analysis. Correlation between degree of ICA stenosis and quantity of intraplaque haemorrhage was assessed by means of regression analysis. Results: Seventy-four patients (20 asymptomatic, 54 symptomatic) were included. The median latency of symptoms was 28 (1,600) days. Intraplaque haemorrhage was common: 54 (73 per cent) of 74 patients. Mean(s.e.m.) cumulative symptom-free survival before operation for patients with no intraplaque haemorrhage was 0·71(0·11), compared with 0·58(0·11) in those exhibiting haemorrhage in less than 50 per cent of the plaque area, and 0·20(0·07) in lesions with over 50 per cent (P = 0·002). A close correlation was observed between the degree of ICA stenosis and haemorrhagic content of the dominant atherosclerotic lesion (r2 = 0·433, P < 0·001). Conclusion: These results confirm the association between intraplaque haemorrhage and the degree of ICA stenosis. They further demonstrate an association between the size of haemorrhage and timing of neurological events, suggesting a causative role for intraplaque haemorrhage in the development of ischaemic neurological events. © 2001 British Journal of Surgery Society Ltd [source] | ||||||||||