In-plane ultrasonic needle tracking using a fiber-optic hydrophone

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Interventional Radiology

Background:

• Percutaneous interventional procedures require accurate needle guidance.
• Current ultrasound (US) imaging faces challenges in precisely locating needle tips, leading to complications.
• Existing methods for improving needle visibility lack accuracy and clinical compatibility.

Purpose of the Study:

• To present a new method for directly visualizing the needle tip during ultrasound-guided procedures.
• To integrate a fiber-optic ultrasound receiver with an imaging probe for real-time needle tip imaging.
• To overcome the limitations of current ultrasound modalities in needle tip localization.

Main Methods:

• A miniature fiber-optic ultrasound hydrophone was integrated into a 20-gauge needle tip.
• Needle tip imaging was interleaved with standard B-mode ultrasound imaging using clinical systems.
• The method was tested in water, ex vivo tissue, and in vivo swine (brachial plexus) and ovine (fetal interventions) models across various insertion angles and depths.

Main Results:

• The integrated system achieved submillimeter axial and lateral needle tip dimensions in ex vivo and in vivo tissues.
• Signal-to-noise ratio (SNR) of the needle tip varied with insertion angle and depth, with values up to 501 observed.
• Successful visualization was demonstrated in swine and ovine models at clinically relevant depths and angles.

Conclusions:

• Direct visualization of the needle tip is achievable using a fiber-optic ultrasound receiver integrated into the needle.
• The method provides visualization at depths and angles relevant for nerve blocks and fetal interventions.
• This technique holds significant potential to improve the safety and efficiency of ultrasound-guided needle insertions.