| Part 1Investigating the corticospinal tract in patients with mild frontal lobe contusion with diffusion tensor imaging (DTI)Objective The motor function of chronic fronto-occipital contrecoup injury patients declines to to some extent, this dysfunction emerge from structural damages of the brain. This study aims to investigate the injury of the corticospinal tract in patients with mild fronto-occipital contrecoup injury by using diffusion tensor imaging (DTI). Methods 15 patients with mild fronto-occipital contrecoup injury and 21 patients control subjects recruited in this study were scanned by using 1.5T Signa GE magnetic resonance imaging. The glasgow outcome scale (GOS) was used to measure the walking ability. Statistical Parametric Mapping software (SPM8) was used to compare the whole brain FA map of the two groups. Results Compared to control subjects, patients with chronic fronto-occipital contrecoup injury had decreased FA values across all the brain, especially in the frontal lobe, occipital lobe, temporal lobe, corpus callosum, cerebellum white matter and deep white matter. Compared to the normal control (0.44±0.03), the patients group had significantly lower mean FA values of the whole brain. Conclusions Diffuse white matter abnormalities was observed across the brain in chronic fronto-occipital contrecoup injury patient, these white matter abnormalities may underlying the impairment of the motor function.Part 2Investigating the damage of the corticospinal Tract in patients with mild frontal lobe contusion by diffusion tensor tractographyObjective ROI was selected to do corticospinal tract fiber tracking and to evaluate the damage to the corticospinal tract of patients with chronic frontal lobe contusion. Methods The lesion side of the image data was fliped to the left in some patiens of whom lesion side was right. TrackVis & Diffusion Toolkit software were used to do diffusion tensor tractography in 15 patients with chronic frontal lobe contusion and 21 normal volunteers, corticospinal tract from top to bottom was isolated by selecting the region of interest (ROI) of cerebral peduncle.The fiber numbers of cortical spinal tract of both side were accquired, the fiber number difference of corticospinal tract between the two sides (DTN) in two groups was calculated (right minus left) Results Compared to control subjects, the number of corticospinal tract in patients was significant lower than that of the normal volunteers’, the DTN value of corticospinal tract in patients was significantly higher than that of normal volunteers’(P<0.05). Conclusions As GOS value of patients is between 4 and 5, which means the patients with chronic frontal lobe contusion have a good prognosis. So the significant reduction in the number of corticospinal tract may suggest that the MRI mesurements is more sensitive that glasgow outcome scale. This noninvasive method is more objective and clear to reflect the state of corticospinal tract in patients with chronic frontal lobe contusion. |
