Objective To evaluate the feasibility of 4-channel functional electrical stimulation(FES)in the treatment of cerebral ischemic stroke sequelae using 3.0T magnetic resonance diffusion tensor imaging(DTI).Methods Patients with the sequelae of cerebral ischemic stroke who were admitted to Shandong Provincial Third Hospital from February 2020 to November 2022(n=100)were enrolled and divided into two groups at a ratio of 1:1 according to random numbers generated by Excel.Besides routine rehabilitation training,observation group was given 4-channel FES to stimulate the quadriceps muscle,tibialis anterior muscle,gastrocnemius muscle and hamstring muscle of the affected lower extremity by simulating the time series of muscle contraction of normal subjects when walking;while control group was treated with dual-channel FES,with electrodes placed on the muscle points of the tibialis anterior muscle and peroneus longus and brevis muscles of the affected lower extremity for stimulation.All patients received 3.0T MRI before and after treatment,and the relevant DTI parameters were recorded and compared.Meanwhile,Berg balance scale(BBS)and Fugl-Meyer assessment scale for lower extremity(FMA-LE)were used to evaluate the therapeutic efficacies in two groups of patients with the sequelae of cerebral ischemic stroke.The correlation of BBS/FMA-LE score with DTI parameters in observation group was also discussed.Results After treatment,both FMA-LE and BBS scores of control group and observation group showed increasing trends,and the increases in observation group were more obvious(P<0.05).After 2 weeks of treatment,compared with control group,observation group had higher FMA-LE score,BBS score,fractional anisotropy(FA),average diffusion coefficient(DCavg)and volume ratio anisotropy(VRA),but lower exponential attenuation(Exat)(all P<0.05).In observation group,FMA-LE score was positively correlated with FA,DCavg and VRA,but negatively correlated with Exat;while BBS score was positively correlated with FA and VRA,but negatively correlated with Exat,and had no significant correlation with DCavg.Conclusion DTI can be used to evaluate the therapeutic efficacy of 4-channel FES on the sequelae of cerebral ischemic stroke,and its parameters are significantly correlated with BBS score and FMA-LE score,suggesting that MRI can assist doctors in understanding the correlation between neurological impairments and neuropathological changes,and provide reference for accurate assessment of prognosis and formulation of individualized rehabilitation program.