Monitoring skeletal muscle chronic fatty degenerations with fast T1-mapping
To develop a fast, high-resolution T1-mapping sequence dedicated to skeletal muscle imaging, and to evaluate the potential of T1 as a robust and sensitive biomarker for the monitoring of chronic fatty degenerations in a dystrophic disease.
The magnetic resonance imaging sequence consisted of the acquisition of a 1,000-radial-spokes FLASH echo-train following magnetisation inversion, resulting in 10s scan time per slice. Temporal image series were reconstructed using compressed sensing and T1 maps were computed using Bloch simulations. Ten healthy volunteers and 30 patients suffering from Becker muscular dystrophy (BMD) participated in this prospective study, in order to evaluate the repeatability, the precision and the sensitivity of the proposed approach. Intramuscular fat fraction (FF) was also measured using a standard three-point Dixon method. The protocol was approved by a local ethics committee.
The mean T1 evaluated in the thighs muscles of healthy volunteers was 1,199 ± 45 ms, with a coefficient of reproducibility of 2.3%. Mean T1 values were statistically decreased in the thighs of BMD patients and were linearly correlated with intramuscular FF (R = -0.98).
T1-mapping is a good candidate for fast, sensitive and quantitative monitoring of fatty infiltrations in neuromuscular disorders.
• A T1 mapping sequence dedicated to skeletal muscle imaging was implemented.
• The acquisition time was 10 s per slice.
• Muscle T1 values were significantly decreased in dystrophic muscles compared to healthy muscles.
• T1 values correlated with intramuscular fat fraction measured by three-point Dixon.
• T1 represents an alternative biomarker for monitoring fatty infiltrations in neuromuscular disorders.
KeywordsMagnetic resonance imaging; Skeletal muscle Fatty tissue Quantitative evaluation Image reconstruction
Becker muscular dystrophy
Fast low angle shot
Magnetic resonance imaging
Longitudinal relaxation time
Transverse relaxation time
The authors state that this work has not received any funding.
Compliance with ethical standards
The scientific guarantor of this publication is Benjamin Marty, Ph.D.
Conflict of interest
The authors of this manuscript declare no relationships with any companies, whose products or services may be related to the subject matter of the article.
Statistics and biometry
No complex statistical methods were necessary for this paper.
Written informed consent was obtained from all subjects (patients) in this study.
Institutional Review Board approval was obtained.
• performed at one institution
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