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Uncompromised MRI of knee cartilage while incorporating sensitive sodium MRI

Brinkhof, S. ; Ali Haghnejad, A. ; Ito, K. ; Markenroth Bloch, K. LU and Klomp, D. W.J. (2019) In NMR in Biomedicine
Abstract

Sodium imaging is able to assess changes in ion content, linked to glycosaminoglycan content, which is important to guide orthopeadic procedures such as articular cartilage repair. Sodium imaging is ideally performed using double tuned RF coils, to combine high resolution morphological imaging with biochemical information from sodium imaging to assess ion content. The proton image quality of such coils is often harshly degraded, with up to 50% of SNR or severe acceleration loss as compared to single tuned coils. Reasons are that the number of proton receive channels often severely reduced and double tuning will degrade the intrinsic sensitivity of the RF coil on at least one of the nuclei. However, the aim of this work was to implement... (More)

Sodium imaging is able to assess changes in ion content, linked to glycosaminoglycan content, which is important to guide orthopeadic procedures such as articular cartilage repair. Sodium imaging is ideally performed using double tuned RF coils, to combine high resolution morphological imaging with biochemical information from sodium imaging to assess ion content. The proton image quality of such coils is often harshly degraded, with up to 50% of SNR or severe acceleration loss as compared to single tuned coils. Reasons are that the number of proton receive channels often severely reduced and double tuning will degrade the intrinsic sensitivity of the RF coil on at least one of the nuclei. However, the aim of this work was to implement a double-tuned sodium/proton knee coil setup without deterioration of the proton signal whilst being able to achieve acquisition of high SNR sodium images. A double-tuned knee coil was constructed as a shielded birdcage optimized for sodium and compromised for proton. To exclude any compromise, the proton part of the birdcage is used for transmit only and interfaced to RF amplifiers that can fully mitigate the reduced efficiency. In addition, a 15 channel single tuned proton receiver coil was embedded within the double-resonant birdcage to maintain optimal SNR and acceleration for proton imaging. To validate the efficiency of our coil, the designed coil was compared with the state-of-the-art single-tuned alternative at 7 T. B1+ corrected SNR maps were used to compare both coils on proton performance and g-factor maps were used to compare both coils on acceleration possibilities. The newly constructed double-tuned coil was shown to have comparable proton quality and acceleration possibilities to the single-tuned alternative while also being able to acquire high SNR sodium images.

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Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
7 T, cartilage, knee, sodium
in
NMR in Biomedicine
article number
e4173
publisher
John Wiley & Sons
external identifiers
  • scopus:85072034454
  • pmid:31502337
ISSN
0952-3480
DOI
10.1002/nbm.4173
language
English
LU publication?
yes
id
cbeb153a-1a20-484a-a371-fbc827d1bfb2
date added to LUP
2019-09-18 15:22:01
date last changed
2019-10-15 07:16:51
@article{cbeb153a-1a20-484a-a371-fbc827d1bfb2,
  abstract     = {<p>Sodium imaging is able to assess changes in ion content, linked to glycosaminoglycan content, which is important to guide orthopeadic procedures such as articular cartilage repair. Sodium imaging is ideally performed using double tuned RF coils, to combine high resolution morphological imaging with biochemical information from sodium imaging to assess ion content. The proton image quality of such coils is often harshly degraded, with up to 50% of SNR or severe acceleration loss as compared to single tuned coils. Reasons are that the number of proton receive channels often severely reduced and double tuning will degrade the intrinsic sensitivity of the RF coil on at least one of the nuclei. However, the aim of this work was to implement a double-tuned sodium/proton knee coil setup without deterioration of the proton signal whilst being able to achieve acquisition of high SNR sodium images. A double-tuned knee coil was constructed as a shielded birdcage optimized for sodium and compromised for proton. To exclude any compromise, the proton part of the birdcage is used for transmit only and interfaced to RF amplifiers that can fully mitigate the reduced efficiency. In addition, a 15 channel single tuned proton receiver coil was embedded within the double-resonant birdcage to maintain optimal SNR and acceleration for proton imaging. To validate the efficiency of our coil, the designed coil was compared with the state-of-the-art single-tuned alternative at 7 T. B1+ corrected SNR maps were used to compare both coils on proton performance and g-factor maps were used to compare both coils on acceleration possibilities. The newly constructed double-tuned coil was shown to have comparable proton quality and acceleration possibilities to the single-tuned alternative while also being able to acquire high SNR sodium images.</p>},
  author       = {Brinkhof, S. and Ali Haghnejad, A. and Ito, K. and Markenroth Bloch, K. and Klomp, D. W.J.},
  issn         = {0952-3480},
  language     = {eng},
  publisher    = {John Wiley & Sons},
  series       = {NMR in Biomedicine},
  title        = {Uncompromised MRI of knee cartilage while incorporating sensitive sodium MRI},
  url          = {http://dx.doi.org/10.1002/nbm.4173},
  doi          = {10.1002/nbm.4173},
  year         = {2019},
}