View clinical trials related to Internal Carotid Artery Stenosis.
Filter by:The investigators plan to collect 30 participants with internal carotid artery stenosis to observed the relationship between the degree of internal carotid artery stenosis and fundus vessels （and blood flow）density before operation, and compared with participants without internal carotid artery stenosis.The fundus blood flow density will be observed after intervention operation in order to see whether the operation is effective to improve the density of fundus vessels and blood flow or not.
We aim to determine whether cognitive impairment attributable to cerebral hemodynamic impairment in patients with high-grade asymptomatic carotid artery stenosis is reversible with restoration of flow. To accomplish this aim CREST-H will add on to the NINDS-sponsored CREST-2 trial (parallel, outcome-blinded Phase 3 clinical trials for patients with asymptomatic high-grade carotid artery stenosis which will compare carotid endarterectomy plus intensive medical management (IMM) versus IMM alone (n=1,240), and carotid artery stenting plus IMM versus IMM alone (n=1,240) to prevent stroke and death). CREST-H addresses the intriguing question of whether cognitive impairment can be reversed when it arises from abnormal cerebral hemodynamic perfusion in a hemodynamically impaired subset of the CREST-2 -randomized patients. We will enroll 385 patients from CREST-2, all of whom receive cognitive assessments at baseline and yearly thereafter. We anticipate identifying 100 patients with hemodynamic impairment as measured by an inter-hemispheral MRI perfusion "time to peak" (TTP) delay on the side of stenosis. Among those who are found to be hemodynamically impaired and have baseline cognitive impairment, the cognitive batteries at baseline and at 1 year will determine if those with flow failure who are randomized to a revascularization arm in CREST-2 will have better cognitive outcomes than those in the medical-only arm compared with this treatment difference for those who have no flow failure. We hypothesize that hemodynamically significant "asymptomatic" carotid disease may represent one of the few examples of treatable causes of cognitive impairment. If cognitive decline can be reversed in these patients, then we will have established a new indication for carotid revascularization independent of the risk of recurrent stroke.
The investigators test with the present study design, whether an ultrasound-guided blockade of the cervical plexus in combination with an additional application of local anesthetic to the superficial cervical ansa (facial nerve: cervical branch) leads to an improved quality of anesthesia.
SONOBIRDIE Trial is a randomized, single-blind, sham-controlled study designed for a demonstration of the safety and effectiveness of sonolysis (continual transcranial Doppler (TCD) monitoring) in reduction of risk of stroke or transient ischemic attack (TIA), brain infarctions and cognitive decline using a 2-MHz diagnostic probe with a maximal diagnostic energy on the reduction of risk of brain infarctions by the activation of endogenous fibrinolytic system during carotid endarterectomy (CEA) in patients with ≥ 70% symptomatic or asymptomatic internal carotid artery stenosis. The sample size is based on an expected 2.5% reduction of ischemic stroke, TIA, and death during the 30-day postoperative period in the sonolysis group (estimated prevalence, 1.5 %) compared to the control group (estimated prevalence, 4 %). Pre-study calculations showed that a minimum of 746 patients in each group is needed to reach a significant difference with an alpha value of 0.05 (two-tailed) and a beta value of 0.8 assuming that 10 % would be lost to follow-up or refuse to participate in the study. Consecutive patients will be assigned to the sonolysis or control group by a computer-generated 1:1 randomization. In patients randomized into sonolysis group, middle cerebral artery segment in a depth of 55 mm will be continuously monitored during intervention using a diagnostic 2-MHz TCD probe with a maximal diagnostic energy. In patients randomized into control group, the TCD probe will be fixed in a required position using a special helmet as in sonolysis group patients, but middle cerebral artery segment in a depth of 55 mm will be only localized using a diagnostic 2-MHz TCD probe with a maximal diagnostic energy and the TCD monitoring will be stopped afterwards. Confirmation of the investigators hypothesis that sonothrombolysis is able to activate endogenous fibrinolytic system during CEA with consecutive reduction of ischemic stroke, TIA or death, and the number and volume of brain infarcts, can lead to the increase of the safety of CEA in patients with internal carotid artery stenosis. The investigators can presume that up to 50% of patients indicated for CEA can be treated using these methods in the future.
This study will be conducted in up to 10 hospitals in Europe, up to 75 patients will be enrolled. The purpose of the study is to evaluate any debris that may be captured in the inline filter of the MICHI(TM) Neuroprotection System with Filter (NPS+f) during its use in a transcarotid stenting procedure. The MICHI NPS+f is an embolic protection device that uses reverse flow to protect the brain during stenting of the Internal Carotid Artery. It is CE marked and is used in routine practice for the purpose of this study.
The aim of the project is to demonstrate a fibrinolytic effect of sonothrombolysis (continual transcranial Doppler monitoring) using 2 MHz diagnostic probe on the reduction of risk of brain infarctions due to the activation of endogenous fibrinolytic system during carotid endarterectomy (CEA) and carotid stenting (CS). 240 patients indicated for CEA (120 patients) and CS (120 patients) will be enrolled into the study in order to demonstrate a twenty-percent risk reduction of number and volume of brain infarctions detected using MRI examination 24 hours after CEA or CS in 5% level of significance. Patients will be randomized - subgroup 1 will undergo a 60minute non-diagnostic TCD monitoring during CEA or CS, subgroup 2 will undergo interventions without TCD monitoring. The second aim is to compare number of brain infarctions detected using MRI between CEA and CS patients. Confirmation of the investigators hypothesis that sonothrombolysis is able to activate endogenous fibrinolytic system during CEA or CS with consecutive reduction of the number and volume of brain infarcts, can lead to the increase of the safety of CEA and CS in patients with internal carotid artery stenosis. The investigators can presume that up to 50% of patients indicated for CEA or CS can be treated using these methods in the future. In the Substudy "Risk of brain infarction after carotid endarterectomy and stenting" the the risk of asymptomatic and symptomatic brain infarctions, changes in cognitive functions, as well as morbidity and mortality at 30 days between patients with symptomatic and asymptomatic severe ICA stenoses undergoing elective CEA and CAS will be compared. The sample size of the Substudy was based on an expected 80% difference of new ischemic lesions on DWI-MRI between CEA (estimated prevalence, 30%) and CAS (54%). Pre-study calculations showed that a minimum of 73 patients in each group was needed to reach a significant difference with an alpha value of 0.05 (two-tailed) and a beta value of 0.8 assuming that 15% of subjects would be lost to follow-up or refuse to participate in the study.
A highly desired result during carotid endarterectomy (CEA) is the ability to predict and warn the surgeon if the brain is at risk of damage during the period of time that the carotid artery is cross-clamped for surgical repair of the vessel narrowing. A number of approaches for cerebral monitoring have been developed, including EEG, cerebral oximetry, and measurement of arterial to jugular venous concentration differences of oxygen, glucose or lactate. This study will utilize and compare multiple monitoring approaches for detecting when and if the brain is at risk of injury during CEA. As such, this robust approach to monitoring may permit a more prompt intervention to prevent or limit damage should cerebral ischemia occur. In this study we will compare a processed EEG monitor -- the EEGo, which uses nonlinear analysis to a bispectral (BIS) index monitor, and to the FORE-SIGHT cerebral oximeter to assess the ability of each to identify cerebral ischemia should it occur with carotid artery cross-clamping during CEA. These monitors will be correlated with arterial to jugular venous lactate concentration difference, which has recently been shown to be a sensitive indicator of hemispheric ischemia during CEA.