Approximately 20% of strokes originate from the rupture of an atherosclerotic plaque in the carotid artery. Surgical revascularization, i.e. carotid endarterectomy (CEA), is the treatment of choice for patients with a symptomatic carotid stenosis each year about 3,000 procedures are performed in the Netherlands. Currently, two surgical procedures are performed in clinical practice. Most frequently an endarterectomy is performed using a length incision over the artery, followed by a patch plasty (CEAP), in order to reduce the risk of restenosis. As an alternative the eversion technique (ET) was introduced, in which transversal arteriotomy is performed and the plaque is removed from within. After reconstruction with a patch a >50% restenosis has been described in 6-36% of patients during long-term follow-up. When using the eversion technique this is seen in 1.7-2.5%, while also the risk on adverse events seem to be lower. One of the drivers for atherosclerosis in general is a disturbance of local blood flow. This may lead to turbulence, recirculation and stasis of blood. The subsequent low Wall Shear Stress may lead to the ne formation of plaque that in turn may become instable and cause recurrent ischemic events. Recently, a breakthrough was achieved in the imaging options of flow in the carotid arteries, using Vector Flow Imaging. Using a fully programmable ultrasound machine, over 10,000 frames per second can be captured, in comparison to about 50 in regular ultrasound. This enables the tracking of particles that, after processing will provide the needed flow information. A recent study, comparing flow before and after CEAP has shown that there is significant recirculation after reconstruction. This raises the question whether this would be more optimal after ET, which would support the potential lower incidence of recurrent stenosis.

Inclusion Criteria:

• Presence of carotid artery stenosis (≥50%) according to conventional clinically performed imaging (duplex/CT(A)/MR(A)) for which patient underwent uncomplicated CEA with either a patch plasty or the eversion technique
• ≥18 years old;
• Able to provide signed or oral informed consent
• Carotid artery <25mm below skin

Exclusion Criteria:

• Carotid bifurcation with depth of center bulb lumen ≥2.5cm
• Restenosis after carotid revascularisation at side of interest
• Participating in another clinical study, interfering on outcomes

Patients that underwent a CEA, without residual stenosis after surgery, will be included in this study. Patients with ET will be recruited in two collaborating hospitals (ETZ and MST) at the department of Vascular Surgery. Participants to the CAP-VALUE trial (Rijnstate and Radboud) are included, where already ultrasound measurements after CEAP were acquired.