Quantification of myocardial perfusion using contrast echocardiography: methodological basis of image postprocessing

Area of Science:

• Cardiology
• Medical Imaging
• Ultrasound Technology

Background:

• Intravenous contrast agents enable myocardial perfusion assessment via ultrasound.
• Subjective visual interpretation of perfusion echocardiography can be inaccurate.
• Digital image postprocessing is essential for maximal diagnostic information.

Purpose of the Study:

• To review the theoretical basis and practical aspects of digital postprocessing for contrast echocardiography.
• To discuss techniques for accurate myocardial perfusion analysis using ultrasound contrast agents.
• To provide a foundation for understanding current and future perfusion densitometric systems.

Main Methods:

• Review of prior research on intravascular tracers (e.g., radioactive microspheres).
• Discussion of digital videodensitometric quantification and mathematical function fitting (gamma-variable wash-in/wash-out).
• Analysis of image acquisition modalities and corresponding postprocessing algorithms (temporal and spatial).

Main Results:

• Digital postprocessing techniques, including videodensitometry and mathematical modeling, are well-validated for contrast echocardiography.
• Image registration, background subtraction, and intensity measurement are key components of postprocessing.
• Different image acquisition modes require specific postprocessing algorithms for accurate analysis.

Conclusions:

• Digital postprocessing is vital for accurate and objective myocardial perfusion assessment with contrast echocardiography.
• Established methods for other tracers are applicable to contrast echocardiography.
• Understanding these postprocessing principles is essential for utilizing current and future perfusion imaging systems.