Using ultrasound CBE imaging without echo shift compensation for temperature estimation

Area of Science:

• Biomedical Ultrasound
• Medical Imaging
• Cancer Therapy

Background:

• Hyperthermia enhances cancer treatment efficacy.
• Ultrasound-based changes in backscattered energy (CBE) imaging is used for temperature monitoring.
• Temperature-induced echo shift complicates accurate CBE imaging.

Purpose of the Study:

• To evaluate the utility of CBE imaging without echo shift compensation for real-time temperature monitoring.
• To simplify algorithms for real-time CBE image computation.

Main Methods:

• Experiments were conducted on phantoms and porcine livers (37°C–45°C).
• In vitro pork tenderloin ablation was performed using microwave irradiation.
• CBE images were constructed using a ratio map of envelope images.

Main Results:

• CBE imaging without compensation effectively estimated temperature variations during heating and ablation.
• Uncompensated CBE showed a stronger temperature-dependent magnitude, indicating enhanced sensitivity.
• The magnitude of CBE as a function of temperature was stronger without compensation.

Conclusions:

• Echo shift compensation may be unnecessary for practical CBE imaging.
• Simplified CBE imaging algorithms can facilitate real-time temperature monitoring.
• This approach improves the feasibility of monitoring hyperthermia and tissue ablation.