Quantification of serial changes in plaque burden using multi-detector computed tomography in experimental...

Area of Science:

• Cardiovascular Imaging
• Atherosclerosis Research
• Medical Technology Assessment

Background:

• Plaque volume changes are crucial surrogate endpoints in anti-atherosclerosis trials.
• Multi-detector computed tomography (MDCT) can detect non-calcified plaques, but its serial assessment capability was untested.
• Magnetic resonance imaging (MRI) is a benchmark for plaque burden assessment.

Purpose of the Study:

• To evaluate the ability of MDCT to detect and quantify serial changes in atheroma burden.
• To compare MDCT's performance against MRI in an animal model of atherosclerosis.

Main Methods:

• Rabbits with induced atherosclerosis were randomized to a plaque-regressing agent or placebo.
• Two 64-slice MDCT angiography and MRI scans were performed pre- and post-treatment.
• Primary endpoint: change in plaque burden (vessel wall volume) measured by MDCT versus MRI.

Main Results:

• MDCT showed a significant plaque burden decrease with the agent (p=0.03), confirmed by MRI (p=0.03).
• No significant changes were observed in the placebo group by either modality.
• Strong correlations (r=0.750, p<0.001 for burden; r=0.657, p=0.020 for change) were found between MDCT and MRI.
• MDCT slightly overestimated plaque burden, with low interobserver variability (2.5+/-0.4%).

Conclusions:

• MDCT accurately documents serial changes in aortic plaque burden in an animal atherosclerosis model.
• MDCT demonstrates good correlation and agreement with MRI.
• MDCT shows low interobserver variability, supporting its use in clinical trials.