Feasibility study of T2 mapping and fat analysis and calculation technique in the evaluation of thigh quadriceps before and after countermovement jump.

BackgroundThe application of quantitative magnetic resonance imaging (MRI) in skeletal muscle is crucial in rehabilitation medicine and competitive sports training.PurposeTo explore the feasibility of evaluating T2 value, proton density fat fraction (PDFF), and cross-sectional area (CSA) of the quadriceps femoris before and after countermovement jump (CMJ) based on T2 mapping and Fat Analysis and Calculation Technique (FACT).Material and MethodsA total of 32 healthy volunteers were recruited and underwent MRI examination of the thigh muscles, including axial T2 mapping and FACT sequence. The T2 value, PDFF, and CSA of the quadriceps femoris, adductor magnus, and gracilis were measured. The peak torque (PT) of the quadriceps femoris was measured using an isokinetic muscle strength system. The differences in MRI parameters before and after CMJ were compared, as well as the differences between sexes.ResultsThe T2 value and CSA of the quadriceps femoris and adductor magnus increased and PDFF decreased after CMJ (P <0.01). The PDFF of the gracilis was significantly higher than that of the vastus lateralis, and the vastus lateralis had a significantly higher PDFF than the other muscles (P <0.01). PT was highly correlated with the CSA of the quadriceps femoris (P <0.001, r = 0.906). CSA and PT of men were higher than those of women (P <0.001).ConclusionT2 mapping and FACT can quantitatively evaluate the differences of T2 value, PDFF, and CSA of different muscles before and after CMJ, which is an important evaluation method for competitive sports training and disease rehabilitation.