正常人小腿肌肉3.0T磁共振扩散张量成像初步研究

In Vivo Diffusion Tensor Imaging of the Human Calf Muscle on 3 Tesla Scanner

目的初步探讨正常人小腿肌肉3T磁共振扩散张量成像(DTI)的可行性及其表现。资料与方法对10例健康志愿者行左小腿肌肉DTI。观察各肌肉的在DWI图、λ1图、λ2图、λ3图、ADC图和FA图上的表现,并分别测量胫骨前肌(TA)、胫骨后肌(TP)、腓骨长肌(PL)、比目鱼肌(SOL)、腓肠肌内侧头(GM)和腓肠肌外侧头(GL)的λ1、λ2、λ3、ADC值和FA值。比较不同肌肉的测量值有无差异。结果在DWI图上,各肌肉清晰显示,TA的信号最低,最高的是SOL。各肌肉在λ1图、λ2图和ADC图上信号无明显差别。SOL的λ1小于其它肌肉(P<0.05)。TA的λ2小于腓肠肌内侧头和外侧头(P<0.05)。TA和TP的λ3低于其它肌肉(P<0.05)。TA的ADC值小于PL、GM及GL(P<0.05)。TA、TP、LP、SOL、GM和GL的FA值分别为0.44±0.03、0.42±0.03、0.37±0.06、0.30±0.03、0.32±0.05和0.33±0.03,不同肌肉的FA值有统计学差异(P=0.000)。结论对正常人小腿肌肉行3T磁共振DTI是可行的,DTI能较好的反映小腿肌肉的扩散特征。

Objective To investigate the feasibility of diffusion tensor imaging （DTI） of the human calf muscle on 3 Tesla scanner. Materials and Methods DTI was performed in ten healthy subjects. The principal, second, and third eigenvalues （λ1、λ2、λ3） , apparent diffusion coefficient （ADC） and fractional anisotropy （FA） were calculated from DTI of musculi tibialis anterior （TA）, musculi tibialis posterior （TP） , musculi peroneus longus （PL）, musculi soleus （SOL） , musculi gastrocnemius medial head（GM） , and musculi gastrocnemius lateral head（GL）. The signal intensity of muscles was compared. Results The muscles were clearly displayed on DWI map with TA lowest signal and SOL highest. No significant difference in the signal intensity between muscles was found on λ1、λ2、and ADC maps. The λ1 of SOL was lower than other muscles （ P 〈 0.05 ） o The λ2 of TA was lower than GM and GL（ P 〈 0.05 ）. The λ3 of TA and TP was lower than other muscles（P 〈0.05 ）, The mean FA value of TA, TP, LP, SOL, GM, and GL was 0.44 ± 0.03, 0.42 ±0.03,0.37 ± 0.06, 0.30 ± 0.03,0.32 ± 0.05, and 0.33 ± 0.03, respectively. There was significant difference in FA between different muscles （P = 0.000）. Conclusion In vivo DTI of the human calf muscle on 3 Tesla scanner could be feasible and reflect diffusion characteristics of muscles.