Active clinical trials for "Carotid Stenosis"

Internal carotid artery (ICA) is intended to supply blood to brain. The carotid bulb located upstream of ICA origin is prone to atherosclerosis. This is an accumulation of fat and calcium in the wall forming a plaque that gradually thickens and leads to carotid stenosis (CS), which causes a decrease in blood flow. The risk of CS is stroke caused either by carotid artery thrombosis (occlusion) or by atherosclerotic plaque fragmentation, some components of which may leak into the brain (embolism). When diagnosing CS, an Echo-Doppler is performed to determine bulb and ICA origin obstruction rates. The reference method of quantifying CS is based on hemodynamic criteria that only allow the diagnosis of high grade stenosis thresholds (50%-70%). Below 50%, low-grade stenosis, patient follow-up is limited and could be based on morphological criteria; ultrasound imaging being a reference technique for human body structures morphological assessment, especially vessels. Two methods of CS morphological quantification with Doppler ultrasound currently exist. Calibre reduction at the maximum of stenosis can be measured by relating the smallest luminal diameter to the vessel diameter at stenosis site (ECST method) or to the downstream ICA diameter (NASCET method). As bulb diameter measures ≈1.8 times that of ICA, ECST appears to be more suitable for CS quantification. For high-grade stenosis, morphological quantification performance is impaired due to extensive calcification of large atheromatous plaques. However, it is possible that less calcified nature of low-grade stenosis and the use of a rigorous methodology will allow reproducible assessment in routine practice. This technique has not yet been evaluated, although it is a frequent situation in patient follow-up.

This will be a pilot study of 9 patients undergoing standard-of-care clinically indicated carotid endarterectomy. The nine patients will receive an injection of Indocyanine green (ICG) at a dose of 0.25 mg/kg (maximum 25 mg) as an intravenous bolus. Immediately following endarterectomy, the resected specimen will be immersed in normal saline. Ex vivo fluorescence reflectance imaging (FRI) and immunohistochemistry will be performed. The investigators hypothesize that compared to controls, ICG-injected patients will demonstrate increased ex vivo and microscopic ICG fluorescence signal within areas of plaque.

The odontological radiology method Panorama is known to be able to spot calcifications in the area of the carotid arteries. The calcifications could be carotid stenoses which is affiliated with an increased risk of stroke. The study aims to investigate if panorama examinations can be used as a starting point for further investigation of the carotid arteries.

This study randomises patients with patients with asymptomatic carotid artery stenosis, to be managed either by providing an intensive 12-week lifestyle modification programme, or standard healthcare.

To compare the incidence of new ischemic brain injury detected with magnetic resonance imaging (MRI) after carotid artery stenting in patients treated with and without proximal cerebral protection (Gore Flow Reversal System).

Background-White matter hyperintensities (WMH), patchy areas of hyperintense signal on T2-weighted or Fluid Attenuated Inversion Recovery sequences on brain magnetic resonance imaging (MRI), are believed to reflect cerebral burden of ischemic damage and are associated to incident stroke, dementia and eventually mortality in otherwise healthy subjects. Also brain atrophy has been related with presence of carotid atherosclerosis and vascular cognitive impairment. Carotid atherosclerosis may contribute to the genesis of WMH. A recent meta-analysis by our group comprising 5306 subjects was able to demonstrate an association between the presence of carotid atherosclerosis and WMH (odds ratio, OR, 1.42, 95% confidence interval [CI] 1.22-1.66). Objective-To evaluate the relation between carotid artery plaque characteristics, cardiovascular risk factors and brain atrophy/WMH burden analyzed quantitatively as number and volume of lesions and as brain volumes, and progression over 18 months of follow up in subjects asymptomatic for cerebrovascular disease with a carotid artery stenosis <70%.

Stenting is an alternative to traditional surgery in the treatment of carotid stenosis.The intra and/or postprocedural cerebral embolization remains the most frequent complication. The type of carotid stent and of cerebral protection are the two most important variables potentially affecting the rate of cerebral microembolization. So far there no consensus on the the best stent and cerebral protection.

Randomized placebo-controlled study with vitamine K2 (Menaquinone-4) in calcified carotid stenosis. We evaluate the plaque remodelling after administration of vitamine, reducing the calcified component.

Subjects referred for a routine CTA (computed tomography angiography) or MRA (magnetic resonance angiography) will be invited to participate in the study and subjects will be involved in the study for between 2 and 12 days. Two to three visits to the study doctor will be required. This study will compare the diagnostic results of Gadobutrol enhanced MRA images with MRA images taken without contrast agent using images from a CTA as the standard of reference, which may have been performed up to 60 days prior to enrolment. If a CTA has not been performed in this prior time period, a CTA is required for the study. MRA and CTA images will be collected for an independent review (blinded read).

The first goal of this study is to investigate whether CE-US is able to accurately identify and quantify neovascularisation in carotid artery plaques. Since this is one of the first studies systematically evaluating the ability of ultrasound in combination with air bubbles to evaluate neovascularisation in carotid artery plaques, the examination will be performed twice with an interval of 1/2 hour on the day before surgery, thus studying the reliability of the method. The second goal of this study is to investigate whether MRI at 3.0 T with a custom-designed 3T carotid coil, using a recently developed pulse sequence, is able to accurately identify and quantify neovascularisation. And the third goal of this study is to make an intermodality comparison of CE-US and MRI regarding their ability to identify and quantify plaque neovascularisation.