High resolution 7T MR imaging in characterizing culprit intracranial atherosclerotic plaques

Area of Science:

• Neuroimaging
• Cardiovascular Imaging
• Radiology

Background:

• Current imaging techniques often underestimate the severity of intracranial atherosclerotic disease (ICAD).
• High-resolution vessel wall imaging (HR-VWI) MRI shows promise in characterizing intracranial plaques.
• This study compares HR-VWI MRI with conventional methods for ICAD assessment.

Purpose of the Study:

• To evaluate the accuracy of HR-VWI MRI in detecting and characterizing intracranial plaques.
• To compare HR-VWI MRI with digital subtraction angiography (DSA), time-of-flight (TOF) MRA, and computed tomography angiogram (CTA).
• To assess the correlation between plaque burden, degree of stenosis, and remodeling index using different imaging modalities.

Main Methods:

• Prospective study of 44 patients with symptomatic ICAD undergoing 7T HR-VWI MRI.
• Calculation of degree of stenosis, plaque burden (PB), and remodeling index (RI).
• Analysis of plaque detection sensitivity, variable correlations, and interobserver agreement for HR-VWI, DSA, TOF-MRA, and CTA.

Main Results:

• HR-VWI MRI demonstrated superior plaque detection sensitivity compared to CTA, TOF-MRA, and DSA.
• Significant positive correlation between plaque burden and stenosis degree was found with HR-VWI MRI, unlike other modalities.
• HR-VWI MRI showed a significant negative correlation between remodeling index and stenosis degree, also not observed with other methods.
• HR-VWI MRI achieved the best inter-rater agreement for culprit plaque detection.

Conclusions:

• Intraluminal measurements of stenosis do not fully represent the extent of ICAD.
• HR-VWI MRI is a more accurate tool for characterizing atherosclerotic plaques in ICAD.
• HR-VWI MRI may become the preferred imaging modality for clinical practice in managing ICAD.