TY - JOUR
T1 - Novel approaches to needle tracking and visualisation
AU - McLeod, G. A.
N1 - Funding Information:
Figure 2 is distributed under the terms of the Creative Commons Attribution Non‐commercial License, Attribution – Share Alike 4.0 which permits any non‐commercial use, distribution and reproduction in any medium, provided the original author(s) and source are credited ( https://creativecommons.org/licenses/by-sa/4.0 ). With acknowledgement to publisher Springer Nature and author, Dr A. Sauter. GM has received funding from B.Braun/Philips in 2018 to conduct two studies investigating the ‘Onvision’ needle tip tracker. He presented data at a BBraun industrial symposia at ESRA 2018, Dublin and ESRA 2019, Bilbao. He is a member of the B.Braun European Scientific Advisory Committee. Micro‐ultrasound research funded by a National Institute of Academic Anaesthesia BJA/RCoA grant 2014 to fund the PhD studentship of Anu Chandra RCoA Research, Education and Travel grant. National Institute of Academic Anaesthesia Ernest Leach Research Fund 2017. No other external funding or competing interests declared.
Publisher Copyright:
© 2021 Association of Anaesthetists
Copyright:
Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2021/1
Y1 - 2021/1
N2 - The accuracy and reliability of ultrasound are still insufficient to guarantee complete and safe nerve block for all patients. Injection of local anaesthetic close to, but not touching, the nerve is key to outcomes, but the exact relationship between the needle tip and nerve epineurium is difficult to evaluate, even with ultrasound. Ultrasound has insufficient resolution, tissues are difficult to discern due to acoustic impedance and needles are more difficult to see with increased angulation. The limitations of ultrasound have shifted the focus of innovation towards bio-markers that help detect needle tip position by utilising the physical properties of tissues, (e.g. pressure, electrical, optics, acoustic and elastic). Although most are at the laboratory stage and results are as yet only available from phantom or cadaver studies, clinical trials are imminent. For example, fine optical fibres placed within the lumen of block needles can measure needle tip pressure. Electrical impedance differentiates between intraneural and perineural needle tip placement. A new tip tracker needle has a piezo element embedded at its distal end that tracks the needle tip in-plane and out-of-plane as a blue/red or green circle depending on its relative location within the beam. Micro-ultrasound at the tip of the needle is in development. Early images using 40MHz in anaesthetised pigs reveal muscle striation, distinct epineurium and 30–40 fascicles > 75 micron in diameter. The next few years will see a technological revolution in tip-tracking technology that has the potential to improve patient safety and, in doing so, change practice.
AB - The accuracy and reliability of ultrasound are still insufficient to guarantee complete and safe nerve block for all patients. Injection of local anaesthetic close to, but not touching, the nerve is key to outcomes, but the exact relationship between the needle tip and nerve epineurium is difficult to evaluate, even with ultrasound. Ultrasound has insufficient resolution, tissues are difficult to discern due to acoustic impedance and needles are more difficult to see with increased angulation. The limitations of ultrasound have shifted the focus of innovation towards bio-markers that help detect needle tip position by utilising the physical properties of tissues, (e.g. pressure, electrical, optics, acoustic and elastic). Although most are at the laboratory stage and results are as yet only available from phantom or cadaver studies, clinical trials are imminent. For example, fine optical fibres placed within the lumen of block needles can measure needle tip pressure. Electrical impedance differentiates between intraneural and perineural needle tip placement. A new tip tracker needle has a piezo element embedded at its distal end that tracks the needle tip in-plane and out-of-plane as a blue/red or green circle depending on its relative location within the beam. Micro-ultrasound at the tip of the needle is in development. Early images using 40MHz in anaesthetised pigs reveal muscle striation, distinct epineurium and 30–40 fascicles > 75 micron in diameter. The next few years will see a technological revolution in tip-tracking technology that has the potential to improve patient safety and, in doing so, change practice.
KW - needle
KW - nerve block
KW - simulation
KW - technology
KW - ultrasonography
UR - http://www.scopus.com/inward/record.url?scp=85099081531&partnerID=8YFLogxK
U2 - 10.1111/anae.15232
DO - 10.1111/anae.15232
M3 - Review article
C2 - 33426657
AN - SCOPUS:85099081531
SN - 0003-2409
VL - 76
SP - 160
EP - 170
JO - Anaesthesia
JF - Anaesthesia
IS - S1
ER -