Time domain echo pattern evaluations from normal and atherosclerotic arterial walls: a study in vitro

Area of Science:

• Vascular Biology
• Biomedical Ultrasound
• Pathology

Background:

• Atherosclerosis involves plaque buildup in arterial walls.
• Understanding the acoustic properties of arterial tissues is crucial for diagnosis.
• The aqueous phase-intima interface's contribution to ultrasound signals is not fully characterized.

Purpose of the Study:

• To quantitatively assess the role of the aqueous phase-intima interface in normal and atherosclerotic human arteries.
• To differentiate between various stages of atherosclerotic plaque using ultrasound reflection characteristics.

Main Methods:

• In vitro analysis of 75 human fresh arterial specimens (15 normal, 15 fatty, 15 fibrofatty, 15 fibrous, 15 calcific).
• Utilized a broadband transducer (4 to 14 MHz) for ultrasound signal acquisition.
• Measured the aqueous phase-intima reflection in decibels (dB).

Main Results:

• The aqueous phase-intima reflection was significantly lowest in fatty plaques (-35.3 +/- 2.5 dB).
• Normal (-13.2 +/- 8.8 dB), fibrofatty (-20.4 +/- 8.3 dB), fibrous (-13.0 +/- 9.7 dB), and calcific (-5.9 +/- 3.4 dB) plaques exhibited higher reflections.
• Low amplitude echoes from the intima-media transition were observed in normal and fatty samples, contrasting with stronger reflections in other pathological subsets.

Conclusions:

• The time-domain echo pattern of the arterial wall can serve as a valuable indicator of plaque structure.
• Distinct ultrasound reflection patterns differentiate normal arterial walls from various atherosclerotic plaque types.
• Quantitative analysis of the aqueous phase-intima interface provides insights into arterial wall composition and pathology.