Asymptomatic carotid disease--a new tool for assessing neurological risk

Area of Science:

• Vascular Ultrasound
• Medical Imaging Analysis
• Stroke Prevention

Background:

• Active carotid plaques are linked to atheroembolism and neurological events, necessitating accurate identification for stroke prevention.
• High-definition ultrasound (HDU) offers insights into carotid plaque structure and vulnerability.
• Assessing plaque activity is vital for predicting ischemic brain events.

Purpose of the Study:

• To introduce a novel computer-assisted HDU method for analyzing carotid plaque echomorphology.
• To develop and validate an enhanced activity index (EAI) for risk stratification of carotid plaques.
• To compare the diagnostic performance of EAI against existing methods for identifying symptomatic plaques.

Main Methods:

• Utilized B-mode ultrasound scans and image processing algorithms to extract plaque echomorphology characteristics (ulceration, echolucent areas, echoheterogeneity).
• Combined echomorphology with stenosis severity to calculate the enhanced activity index (EAI).
• Evaluated EAI performance using receiver-operating characteristic (ROC) analysis and leave-one-patient-out cross-validation on 146 carotid plaques.

Main Results:

• The EAI demonstrated high accuracy (up to 77%) in predicting which asymptomatic plaques would develop symptoms.
• EAI showed superior classification performance compared to degree of stenosis and the earlier activity index (AI).
• The study identified an optimal EAI cutoff for distinguishing active from inactive carotid plaques.

Conclusions:

• The enhanced activity index (EAI) is a noninvasive and easily obtainable parameter for accurately estimating neurological risk associated with carotid plaques.
• This computer-assisted HDU method provides a valuable tool for stroke risk assessment in patients with carotid bifurcation stenosis.
• Accurate identification of active carotid plaques using EAI can significantly aid in stroke prevention strategies.