Table 1.

The table presents comparison of the different imaging modalities.

Imaging Modality	Advantages	Limitations
USG	Non invasive Enables qualitative assessment of carotid plaques. High spatial resolution required for measuring intima-media thickness.	Limited to shallow vascular beds. Quality is limited by echo windows and calcification. Not indicating whether the thickening is because of intima or media infiltration or hypertrophy. Operator-dependent and has lower reproducibility.
CEUS	Gives information about plaque composition, and structure. Low rate of adverse reactions.	Strongly operator dependent. Cost of contrast media.
IVUS	High image quality direct real-time imaging of atherosclerosis and the vessel. Can assess the structure of atherosclerotic plaque.	Invasive procedure.
CT	Fast. Relatively inexpensive. Suitable for detecting calcifications in atherosclerotic plaque.	Hemorrhage and thrombus could not reliably be distinguished from lipid. Not effective in detecting other components of high-risk plaques: thin-capped fibroma and the presence of inflammatory cells. X-rays patient exposition.
MRI	Not exposing to ionizing radiation. Enables the assessment of intra-plaque hemorrhage and the integrity of the fibrous sheath. Detects positive arterial remodeling in asymptomatic patients with subclinical atherosclerosis.	Prone to unwanted signal loss due to complex flow patterns.

USG—ultrasonography CEUS—contrast-enhanced ultra sonography, CT—computed tomography, MRI—magnetic resonance imaging.