A sensitive TLRH targeted imaging technique for ultrasonic molecular imaging

Area of Science:

• Biomedical Engineering
• Ultrasound Imaging
• Molecular Imaging

Background:

• Ultrasound molecular imaging aims to detect microbubbles bound to specific vascular receptors.
• Distinguishing bound microbubbles from free ones and surrounding tissue is crucial for practical application.
• Existing methods require sensitive and selective detection techniques.

Purpose of the Study:

• To develop and implement a targeted ultrasound imaging technique for sensitive and selective detection of bound microbubbles.
• To improve the practical application of ultrasound molecular imaging by enhancing microbubble detection capabilities.

Main Methods:

• Utilized a transmission at a low frequency and reception at a high frequency (TLRH) technique with a multifrequency colinear array.
• Integrated an acoustic radiation force subsequence for enhanced microbubble accumulation.
• Processed radiofrequency (RF) data to differentiate between tissue, free microbubbles, and bound microbubbles.

Main Results:

• Achieved a high contrast-to-tissue ratio of up to 34 dB.
• Demonstrated high sensitivity to bound microbubbles, with a bound-to-free microbubble echo ratio up to 23 dB.
• Evaluated the impact of acoustic pressure, radiation force, and filters on imaging quality.

Conclusions:

• The developed TLRH targeted imaging method provides sensitive and selective detection of bound microbubbles.
• This technique is effective for ultrasound molecularly targeted imaging.
• The findings support the advancement of ultrasound-based molecular imaging.