A Radiological Clip Design Using Ultrasound Identification to Improve Localization.

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Acoustic Signal Processing

Background:

• Radiological clips mark breast cancer lesions during neoadjuvant chemotherapy (NAC).
• Ultrasound is the preferred imaging modality for NAC monitoring.
• Existing clips can lose visibility during NAC, hindering accurate monitoring.

Purpose of the Study:

• To demonstrate a novel ultrasound-based system for active radiological clip localization.
• To develop a method for encoding identification numbers within acoustic signals from clips.
• To improve the reliability and accuracy of clip localization in ultrasound imaging.

Main Methods:

• A custom circuit and microcontroller (Teensy 4.0) were used to create an ultrasound identification (USID) clip embedded in a phantom.
• The USID clip transmitted acoustic signals detected by an ultrasound transducer.
• Imaging was performed using a Philips L7-4 array and Verasonics Vantage 128 system in pulse inversion mode, with cross-correlation analysis for localization.

Main Results:

• USID signals were successfully detected and visualized on B-mode ultrasound images.
• Sub-millimeter localization accuracy was achieved.
• An average detection rate of 98.1% was recorded across over 30,000 frames.

Conclusions:

• The developed USID clip reliably produces identifiable, distinguishable, and localizable signals.
• This technology offers a promising solution for overcoming visibility issues with traditional radiological clips.
• The system enables accurate and wireless localization of multiple clips with distinct IDs.