ECG Gated Ultrasonic Small Animal Imaging

Area of Science:

• Biomedical Engineering
• Cardiovascular Research
• Medical Imaging Technology

Background:

• Echocardiography is crucial for diagnosing cardiac function, with mouse models offering insights into human cardiovascular disease.
• Existing clinical ultrasound systems lack the necessary spatial and temporal resolution for effective murine cardiac imaging.
• High-frequency ultrasound (≥ 20 MHz) is required for the ~100 μm resolution needed in mouse studies, but often uses slow mechanical scanning.

Purpose of the Study:

• To develop a high-frequency ultrasonic imaging system with electrocardiography gating for enhanced murine cardiac imaging.
• To achieve both high spatial resolution and high effective temporal resolution for dynamic cardiac motion visualization.
• To overcome the limitations of conventional echocardiography in preclinical cardiovascular research.

Main Methods:

• Construction of a high-frequency ultrasonic imaging system (≥ 20 MHz) incorporating electrocardiography gating.
• Utilization of the R-wave trigger signal from murine electrocardiography for precise timing.
• Implementation of block scanning and line scanning modes for image data acquisition.

Main Results:

• The developed system provides high spatial resolution (~100 μm) and high effective temporal resolution.
• Electrocardiography gating enables retrospective reconstruction of cardiac images (systole/diastole) in block scanning mode.
• Line scanning mode allows imaging throughout the entire cardiac cycle, with effective frame rates up to 2 kHz.

Conclusions:

• The novel high-frequency echocardiography system with ECG gating significantly improves murine cardiac imaging capabilities.
• This technology offers a powerful tool for preclinical cardiovascular research, bridging the gap between mouse models and human disease.
• The high frame rates achieved are crucial for accurately assessing the rapid dynamics of the mouse heart.