Zero-crossing tracking technique for noninvasive ultrasonic temperature estimation

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Acoustics

Background:

• Ultrasound imaging relies on radio frequency (RF) echo analysis.
• Temperature changes in tissue affect ultrasound speed and cause thermal expansion.
• Accurate temperature monitoring is crucial for various medical applications.

Purpose of the Study:

• To evaluate the feasibility of zero-crossing tracking (ZCT) for temperature estimation using ultrasound.
• To compare the computational efficiency of ZCT with conventional cross-correlation (CCR) techniques.

Main Methods:

• The ZCT technique tracks shifts in zero-crossing instants of ultrasound RF echoes.
• Preheated and postheated A-lines were analyzed to detect local temperature-induced echo shifts.
• Phantom experiments were conducted using a linear array probe and focused ultrasound heating.

Main Results:

• Both ZCT and conventional cross-correlation (CCR) techniques provided similar temperature estimation results.
• The ZCT technique demonstrated up to a 7-fold improvement in computational efficiency compared to CCR.
• ZCT effectively processed RF echo data for temperature change monitoring.

Conclusions:

• The ZCT technique is a feasible and computationally efficient method for ultrasonic temperature estimation.
• ZCT offers superior processing speed, making it a promising alternative for real-time temperature monitoring.
• This technique has potential applications in areas requiring precise thermal monitoring via ultrasound.