TY - JOUR
T1 - Optical signature of nerve tissue—Exploratory ex vivo study comparing optical, histological, and molecular characteristics of different adipose and nerve tissues
AU - Balthasar, Andrea J.R.
AU - Bydlon, Torre M.
AU - Ippel, Hans
AU - van der Voort, Marjolein
AU - Hendriks, Benno H.W.
AU - Lucassen, Gerald W.
AU - van Geffen, Geert Jan
AU - van Kleef, Maarten
AU - van Dijk, Paul
AU - Lataster, Arno
PY - 2018
Y1 - 2018
N2 - Background: During several anesthesiological procedures, needles are inserted through the skin of a patient to target nerves. In most cases, the needle traverses several tissues—skin, subcutaneous adipose tissue, muscles, nerves, and blood vessels—to reach the target nerve. A clear identification of the target nerve can improve the success of the nerve block and reduce the rate of complications. This may be accomplished with diffuse reflectance spectroscopy (DRS) which can provide a quantitative measure of the tissue composition. The goal of the current study was to further explore the morphological, biological, chemical, and optical characteristics of the tissues encountered during needle insertion to improve future DRS classification algorithms. Methods: To compare characteristics of nerve tissue (sciatic nerve) and adipose tissues, the following techniques were used: histology, DRS, absorption spectrophotometry, high-resolution magic-angle spinning nuclear magnetic resonance (HR-MAS NMR) spectroscopy, and solution 2D 13C-1H heteronuclear single-quantum coherence spectroscopy. Tissues from five human freshly frozen cadavers were examined. Results: Histology clearly highlights a higher density of cellular nuclei, collagen, and cytoplasm in fascicular nerve tissue (IFAS). IFAS showed lower absorption of light around 1200 nm and 1750 nm, higher absorption around 1500 nm and 2000 nm, and a shift in the peak observed around 1000 nm. DRS measurements showed a higher water percentage and collagen concentration in IFAS and a lower fat percentage compared to all other tissues. The scattering parameter (b) was highest in IFAS. The HR-MAS NMR data showed three extra chemical peak shifts in IFAS tissue. Conclusion: Collagen, water, and cellular nuclei concentration are clearly different between nerve fascicular tissue and other adipose tissue and explain some of the differences observed in the optical absorption, DRS, and HR-NMR spectra of these tissues. Some differences observed between fascicular nerve tissue and adipose tissues cannot yet be explained but may be helpful in improving the discriminatory capabilities of DRS in anesthesiology procedures. Lasers Surg. Med. 50:948–960, 2018.
AB - Background: During several anesthesiological procedures, needles are inserted through the skin of a patient to target nerves. In most cases, the needle traverses several tissues—skin, subcutaneous adipose tissue, muscles, nerves, and blood vessels—to reach the target nerve. A clear identification of the target nerve can improve the success of the nerve block and reduce the rate of complications. This may be accomplished with diffuse reflectance spectroscopy (DRS) which can provide a quantitative measure of the tissue composition. The goal of the current study was to further explore the morphological, biological, chemical, and optical characteristics of the tissues encountered during needle insertion to improve future DRS classification algorithms. Methods: To compare characteristics of nerve tissue (sciatic nerve) and adipose tissues, the following techniques were used: histology, DRS, absorption spectrophotometry, high-resolution magic-angle spinning nuclear magnetic resonance (HR-MAS NMR) spectroscopy, and solution 2D 13C-1H heteronuclear single-quantum coherence spectroscopy. Tissues from five human freshly frozen cadavers were examined. Results: Histology clearly highlights a higher density of cellular nuclei, collagen, and cytoplasm in fascicular nerve tissue (IFAS). IFAS showed lower absorption of light around 1200 nm and 1750 nm, higher absorption around 1500 nm and 2000 nm, and a shift in the peak observed around 1000 nm. DRS measurements showed a higher water percentage and collagen concentration in IFAS and a lower fat percentage compared to all other tissues. The scattering parameter (b) was highest in IFAS. The HR-MAS NMR data showed three extra chemical peak shifts in IFAS tissue. Conclusion: Collagen, water, and cellular nuclei concentration are clearly different between nerve fascicular tissue and other adipose tissue and explain some of the differences observed in the optical absorption, DRS, and HR-NMR spectra of these tissues. Some differences observed between fascicular nerve tissue and adipose tissues cannot yet be explained but may be helpful in improving the discriminatory capabilities of DRS in anesthesiology procedures. Lasers Surg. Med. 50:948–960, 2018.
KW - absorption
KW - adipose tissue
KW - diffuse reflectance spectroscopy
KW - histology
KW - HR-MAS NMR
KW - nerve fascicle
KW - optical
UR - http://www.scopus.com/inward/record.url?scp=85054829666&partnerID=8YFLogxK
U2 - 10.1002/lsm.22938
DO - 10.1002/lsm.22938
M3 - Article
C2 - 29756651
SN - 0196-8092
VL - 50
SP - 948
EP - 960
JO - Lasers in Surgery and Medicine
JF - Lasers in Surgery and Medicine
IS - 9
ER -