Medial lemniscus lesion in pediatric hemiplegic patients without corticospinal tract and posterior thalamic radiation lesion.

ABSTRACT

OBJECTIVES: Using diffusion tensor imaging (DTI), we investigated the state of medial lemniscus (ML), corticospinal tract (CST), and posterior thalamic radiation (PTR), which were expected as probable reasons for clinical hemiplegia in pediatric patients, especially those who showed impaired fine motor control and proprioception, but no definite motor weakness or spasticity. METHODS: We recruited 13 hemiplegic patients and 8 age-matched healthy control subjects. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) for the bilateral ML, CST, and PTR were calculated and compared between the affected hemisphere of the patient (AP), the unaffected hemisphere of the patient (UP), and the mean value of the bilateral hemispheres in control subjects (MC). RESULTS: FA and ADC values for the CST and PTR did not differ significantly between the AP, UP, and MC subgroups (p > 0.05). However, the FA value for the ML in AP showed a significant decrease, compared with that in UP (p = 0.012) and MC (p = 0.047). DTT for the CST and PTR showed preserved integrity and ML in the UP also had continuity to the cortex; however, ML in AP showed disruption. CONCLUSIONS: Using DTI, we demonstrated that the ML lesion might be related to clinical hemiplegia in pediatric patients.