ObjectiveTo analyze the structural changes of default mode network(DMN) in patients with traumatic brain injury(TBI) in the acute phase, and explore the application value of DMN in the early diagnosis of attention disorder after TBI.

MethodsForty-five patients with TBI were set as the TBI group, the structural integrity of DMN was evaluated using diffusion tensor imaging(DTI) during the acute phase, and the attention scale was used to evaluate the patient's attention disorder during convalescence.Thirty healthy volunteers were set as the control group.The MRI-related parameters of TBI patients were analyzed, and compared with the control group.The correlation between the parameters of DTI and cognitive function score was explored.

ResultsCompared with the control group, the fractional anisotropy(FA) of brain region decreased(P < 0.01), and the apparent diffusion coefficient(ADC) of genitals of corpus callosum(gCC) increased in the acute phase(P < 0.01).In the convalescence period, the scores of attention scale in TBI patients were significantly longer than those in control group(P < 0.01).The results of the scores of DMN structure changes in the acute phase and scores of convalescence attention scale in the TBI patients showed that the sum of FA value of Cing, gCC and superior occipitofrontal fascicle(SFOF) were negatively correlated with the sumup time of each part of Stroop colour word scale Victoria version(P < 0.05, R²=0.291), and the FA value of SFOF was negatively correlated with the time of part C in VST(P < 0.05, R²=0.396).

ConclusionsThe interruption of fiber connection in TBI patients is the key factor of damage of DMN structure.The damage of DMN structure can be used as a useful marker for the early diagnosis of attention disorder.