Longitudinal White Matter Alteration in Prolonged Disorders of Consciousness due to Traffic Accidents

Objectives: We analyzed longitudinal white matter alterations by diffusion tensor imaging (DTI) in patients with prolonged disorders of consciousness (PDC). Participants: Seventeen patients with PDC having an average of 328.8 days post-injury and eleven control participants. Main measures: All participants underwent two DTI studies. Fractional anisotropy (FA) values were analyzed using whole-brain analysis (WBA) of 7 patients with no marked brain deformities; mean FA values of forceps minor (mFAFM) were subsequently measured by regional-brain analysis (RBA). Relationships between WB and regional FA values and recovery from PDC were evaluated. Results: WBA in the PDC group showed that FA values were significantly lower in multiple white matter regions (P < 0.05), particularly in part of the forceps minor, in the second scan than they were in the first scan. RBA showed that mFAFM significantly decreased (P < 0.01). Further, WBA revealed that a significant positive correlation was observed between the degree of recovery from PDC and the difference in the number of voxels with FA values > 0.2 (r = 0.65, P < 0.01) between the first and second scans. Conclusion: Our results showed microstructural white matter changes in patients with PDC, suggesting recovery from PDC with long-term treatment.