Application of diffusion tensor imaging in prognosis evaluation in patients with moderate and severe diffuse axonal injury

Abstract

Objective To investigate the application of diffusion tensor imaging (DTI) in evaluating prognosis of patients with moderate and severe diffuse axonal injury (DAI). Methods A prospective cohort study was made on 35 patients with moderate and severe DAI, who were enrolled from June 2013 to December 2015 as study group. There were 21 males and 14 females, with age of (55.1±11.6) years. The Glasgow coma scale (GCS) was (8.2±2.9)points on admission. Moderate DAI was seen in 20 patients and severe DAI in 15 patients. Other 15 healthy volunteers were selected as control group. Fractional anisotropy (FA) was measured by DTI in three areas of interests as follows: the corpus callosum, thalamus, and brainstem areas. Glasgow outcome scale (GOS) was adopted to assess the prognosis of DAI patients at 6 months after the injury. The FA values of the three areas between study group and control group as well as FA values of patients when they were admitted to hospital and 6 months after injury were measured. In this way, the relationship between the FA values of different areas of interests in DAI patients on admission and the prognosis 6 months after injury was analyzed. Results The FA values of the corpus callosum, thalamus and brainstem area in study group were all lower than those in control group (P<0.05). Further, FA values of the corpus callosum, thalamus, brainstem area in severe DAI patients were lower than those of moderate DAI patients (P<0.05). FA values of the corpus callosum, thalamus, brain stem areas in DAI patients at 6 months after injury were lower than those of corresponding areas when DAI patients were admitted to hospital (P<0.05). FA values of the corpus callosum, thalamus and brain stem on admission were significantly positively correlated with GOS at 6 months after injury (P<0.05). Conclusions Lower FA values of the corpus callosum, thalamus and brainstem area in patients with moderate and severe DAI are associated with more severe injury and worse prognosis. DTI scans can be used as a valuable tool to evaluate the prognosis of DAI patients. Key words: Diffuse axonal injury; Diffusion tensor imaging; Prognosis