Multispectral photoacoustic imaging of nerves with a clinical ultrasound system

Jean Martial Mari; Simeon West; Paul C. Beard; Adrien E. Desjardins

doi:10.1117/12.2036717

3 March 2014 Multispectral photoacoustic imaging of nerves with a clinical ultrasound system

Jean Martial Mari, Simeon West, Paul C. Beard, Adrien E. Desjardins

Proceedings Volume 8943, Photons Plus Ultrasound: Imaging and Sensing 2014; 89430W (2014) https://doi.org/10.1117/12.2036717
Event: SPIE BiOS, 2014, San Francisco, California, United States

Abstract

Accurate and efficient identification of nerves is of great importance during many ultrasound-guided clinical procedures, including nerve blocks and prostate biopsies. It can be challenging to visualise nerves with conventional ultrasound imaging, however. One of the challenges is that nerves can have very similar appearances to nearby structures such as tendons. Several recent studies have highlighted the potential of near-infrared optical spectroscopy for differentiating nerves and adjacent tissues, as this modality can be sensitive to optical absorption of lipids that are present in intra- and extra-neural adipose tissue and in the myelin sheaths. These studies were limited to point measurements, however. In this pilot study, a custom photoacoustic system with a clinical ultrasound imaging probe was used to acquire multi-spectral photoacoustic images of nerves and tendons from swine ex vivo, across the wavelength range of 1100 to 1300 nm. Photoacoustic images were processed and overlaid in colour onto co-registered conventional ultrasound images that were acquired with the same imaging probe. A pronounced optical absorption peak centred at 1210 nm was observed in the photoacoustic signals obtained from nerves, and it was absent in those obtained from tendons. This absorption peak, which is consistent with the presence of lipids, provides a novel image contrast mechanism to significantly enhance the visualization of nerves. In particular, image contrast for nerves was up to 5.5 times greater with photoacoustic imaging (0.82 ± 0.15) than with conventional ultrasound imaging (0.148 ± 0.002), with a maximum contrast of 0.95 ± 0.02 obtained in photoacoustic mode. This pilot study demonstrates the potential of photoacoustic imaging to improve clinical outcomes in ultrasound-guided interventions in regional anaesthesia and interventional oncology.

Citation Download Citation

Jean Martial Mari, Simeon West, Paul C. Beard, and Adrien E. Desjardins "Multispectral photoacoustic imaging of nerves with a clinical ultrasound system", Proc. SPIE 8943, Photons Plus Ultrasound: Imaging and Sensing 2014, 89430W (3 March 2014); https://doi.org/10.1117/12.2036717

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available