The clinical value of diffusion tensor imaging for predicting the recovery of walking ability after middle cerebral artery infarction / 中华物理医学与康复杂志

ABSTRACT

Objective:To explore the changes in the diffusion tensor imaging (DTI) parameters of the pontocerebellar tract 3 months and one year after ischemic stroke and analyze the data′s potential for predicting long-term motor outcomes.Methods:Thirty patients with middle cerebral artery infarction were prospectively studied using DTI within 3 months and 1 year after the onset. A region of interest-based analysis was performed for the fractional anisotropy (FA) of the middle cerebellar peduncles (MCP) in the pontocerebellar fibers (PCF). Neurological functioning was evaluated using the National Institutes of Health Stroke Scale and the degree of paresis was assessed at the same time using paresis grading. At one year after the onset, balance function, functional prognosis and self-care ability were evaluated using the Brunel Balance Scale, the modified Rankine Scale and the Functional Independence Scale respectively.Results:The average FA on the healthy side 3 months and 1 year after onset was significantly less than on the affected side at each time point. The ratio of the FA of the affected side to that of the unaffected side (rFA) in the PCF correlated significantly with the average paresis scores of the lower and upper extremity and the total paresis score at each time point. Moreover, the rFA of the PCF was significantly correlated with the average functional independence score, the prognosis for the upper and lower extremities as well as motor functioning. The area ratio under the ROC curve of the PCF for predicting lower extremity motor outcome was 0.84, and the optimal threshold was 0.92 (sensitivity 71.4%, specificity 73.9%). The area ratio under the ROC curve was not a significant predictor of upper extremity motor outcome.Conclusion:The DTI parameter rFA of the PCF in patients with subacute middle cerebral artery infarction can help to predict the long-term recovery of motor ability. It can serve as an important reference index for predicting the long-term motor ability of the lower limbs.