Direct imaging and quantification of carotid plaque calcification

Area of Science:

• Medical Imaging
• Cardiovascular Research
• Biophysics

Background:

• Carotid plaque calcification is typically visualized as a signal void in standard MRI.
• Accurate characterization of plaque composition is crucial for assessing cardiovascular risk.

Purpose of the Study:

• To evaluate an adiabatic inversion recovery prepared two-dimensional ultrashort echo time (2D UTE) sequence for imaging and characterizing carotid plaque calcification.
• To compare MRI-derived parameters with micro-CT imaging for validation.

Main Methods:

• A novel 2D UTE sequence with adiabatic inversion recovery was employed on a 3-T clinical scanner.
• T(1), T(2)*, and free water content were measured in seven carotid plaque samples.
• Results were correlated with micro-computed tomography (micro-CT) imaging and conventional MRI sequences.

Main Results:

• The 2D UTE sequence demonstrated close correspondence with micro-CT in visualizing carotid plaque calcification.
• Significant variations in T(1), T(2)*, and free water content were observed across samples.
• Strong correlations were found between MRI parameters (T(1), T(2)*, free water) and CT-measured mineral density.

Conclusions:

• The developed MRI technique effectively images and characterizes carotid plaque calcification.
• Quantitative MRI parameters correlate well with mineral density, offering potential for non-invasive plaque assessment.