Research on Ultrasound Diagnostic Criteria for Intracranial and Extracranial Arterial Serial Stenosis

This study retrospectively and consecutively enrolled 700 patients diagnosed with either 1) severe extracranial internal carotid artery stenosis combined with ipsilateral middle cerebral artery (MCA) tandem stenosis, or 2) unilateral severe vertebral artery (VA) origin stenosis combined with intracranial V4 segment tandem stenosis, who underwent carotid artery stenting or vertebral artery stenting at our institution. Demographic information, vascular ultrasound findings, and imaging examination results were collected and recorded. All enrolled patients underwent a 1-year follow-up investigation. Follow-up data included vascular ultrasound results, laboratory test results, imaging findings, clinical symptoms (ischemic stroke, transient ischemic attack, hemorrhagic stroke), and documentation of endpoint events. The primary endpoint was the 12-month incidence of new-onset stroke events, defined as ischemic stroke, transient ischemic attack, or hemorrhagic stroke.

The study utilized transcranial color-coded Doppler (TCCD) and transcranial Doppler (TCD) hemodynamic parameters to ultrasonically grade MCA stenosis severity in patients with severe extracranial internal carotid artery stenosis and intracranial V4 segment stenosis severity in patients with severe VA origin stenosis. The goal was to establish ultrasound diagnostic criteria and provide a reference basis for clinical treatment decision-making. Additionally, the distribution of stroke risk factors was analyzed, and a risk identification and prediction model for stroke was developed and evaluated.

Patients were first stratified into two groups based on the presence or absence of collateral circulation. Further subgroup classification was performed according to the degree of MCA stenosis (on digital subtraction angiography [DSA]) or V4 segment stenosis: no stenosis, mild stenosis, moderate stenosis, and severe stenosis. Finally, patients were categorized into either the endpoint event group or the non-event group based on the occurrence of endpoint events during follow-up.

Inclusion criteria

• Patients diagnosed by carotid ultrasound with severe stenosis of the extracranial segment of the internal carotid artery or severe stenosis of the initial segment of the unilateral vertebral artery;
• Perform stent placement surgery within 2 weeks of ultrasound examination, and perform DSA and CTA examinations;
• Age ≥ 18 years old;
• Clinical data is complete.

Exclusion criteria

• Bilateral temporal windows are not transparent to sound;
• Patients with severe stenosis of the extracranial segment of the internal carotid artery have ipsilateral MCA occlusion/ipsilateral common carotid artery severe stenosis or occlusion;
• Patients with severe stenosis of the extracranial segment of the internal carotid artery have severe stenosis of the contralateral carotid artery;
• Patients with severe stenosis or occlusion of the anterior circulation in the initial segment of unilateral vertebral artery;
• Severe stenosis or occlusion of bilateral subclavian arteries;
• Vasospasm caused by subarachnoid hemorrhage, etc;
• Related MCA or vertebral artery thrombolysis or endovascular treatment;
• Arrhythmias such as atrial fibrillation or heart failure that affect velocity measurement;
• CT, MRI, DSA examination contraindications or refusal of examination;
• Severe bleeding disorders or coagulation dysfunction;
• Merge serious diseases of other organs or tissues.