T2-weighted dixon turbo spin echo for accelerated simultaneous grading of whole-body skeletal muscle fat infiltration and edema in patients with neuromuscular diseases

Objective The assessment of fatty infiltration and edema in the musculature of patients with neuromuscular diseases (NMDs) typically requires the separate performance of T₁-weighted and fat-suppressed T₂-weighted sequences. T₂-weighted Dixon turbo spin echo (TSE) enables the generation of T₂-weighted fat- and water-separated images, which can be used to assess both pathologies simultaneously. The present study examines the diagnostic performance of T₂-weighted Dixon TSE compared with the standard sequences in 10 patients with NMDs and 10 healthy subjects. Methods Whole-body magnetic resonance imaging was performed including T₁-weighted Dixon fast field echo, T₂-weighted short-tau inversion recovery, and T₂-weighted Dixon TSE. Fatty infiltration and intramuscular edema were rated by 2 radiologists using visual semiquantitative rating scales. To assess intermethod and interrater agreement, weighted Cohen's κ coefficients were calculated. Results The ratings of fatty infiltration showed high intermethod and high interrater agreement (T₁-weighted Dixon fast field echo vs T₂-weighted Dixon TSE fat image). The evaluation of edematous changes showed high intermethod and good interrater agreement (T₂-weighted short-tau inversion recovery vs T₂-weighted Dixon TSE water image). Conclusions T₂-weighted Dixon TSE imaging is an alternative for accelerated simultaneous grading of whole-body skeletal muscle fat infiltration and edema in patients with NMDs.