Laser Doppler sensing for blood vessel detection with a biologically inspired steerable needle

Area of Science:

• Biomedical Engineering
• Minimally Invasive Surgery
• Optical Sensing

Background:

• Puncturing blood vessels is a critical risk in minimally invasive brain surgery.
• Current rigid needles require procedural interruption for vessel detection.
• A steerable needle with integrated sensing is needed to improve safety.

Purpose of the Study:

• To develop and validate a novel optical method for detecting blood vessels ahead of a steerable needle.
• To integrate laser Doppler flowmetry (LDF) probes into a biomimetic, multi-segment steerable needle.
• To enable real-time vessel reconstruction for enhanced surgical navigation.

Main Methods:

• Characterization of an LDF probe in a human gray matter tissue phantom.
• Embedding a pair of LDF probes into a four-channel steerable needle.
• Vessel reconstruction using successive measurements to determine depth and off-axis position, predicting orientation via 'detection circles'.

Main Results:

• The LDF probe demonstrated a 2.1 mm penetration depth and 1 mm off-axis detection range at 5 mm/s flow velocity.
• Vessel reconstruction achieved a depth root mean square error (RMSE) of 0.3 mm.
• Angular prediction of vessel orientation yielded an RMSE of 15°.

Conclusions:

• The proposed optical detection system is feasible for integration into steerable needles.
• The system accurately reconstructs vessel location and orientation, offering a promising safety enhancement for neurosurgery.
• This technology holds significant potential for future clinical applications in minimally invasive procedures.