Forensic Medicine Research Of Cognitive Dysfunction After Traumatic Brain Injury

Objective: Traumatic brain injury(TBI) is one of the most common causes of dysfunction in nervous system. The intellectual impairment, daily life and social activities in judicial authentication after traumatic brain injury is the main basis of disability evaluation. Computed tomography(CT) is a clinically important auxiliary examination method after traumatic brain injury. Event related potential(ERP) reflects the cognitive process of the change of the brain’s nerve electrophysiology, and also known as cognitive potential. When people cognitive processing of a project is carried out, potential recorded from the surface of the brain. In this study, we will explore the age, gender and educational level influences cognitive after traumatic brain injury. To explore the relationship between imaging parameters, traumatic brain injury severity and cognitive function after traumatic brain injury. To explore the event related potential P300 and MMN detection in assessing the role of cognitive dysfunction after TBI.Methods: Collecting of TBI group and normal control group, and comparing age, gender and educational level with cognitive dysfunction after TBI. Acute phase of traumatic brain injuries group applied Marshall computed tomography(Marshall CT) imaging classification(less than 48 hours) and applied CT imaging parameters in stability phase of TBI(more than 6 month post-TBI) to explore the relationship among brain injury location, injury degree, cognitive function and disability after TBI. Using event related potential(ERP) in patients with TBI and healthy volunteers with oddball paradigm, Electroencephalogram(EEG) real-time detection and offline analysis, the cognitive were determined by Wechsler adult intelligence scale-revised China(WAIS-RC), Activity of Daily Living(ADL) and China version of social disability screening schedule(C-SDSS). The correlations of cognitive after TBI were detected by visual P300 and Mismatch negative(MMN).Results:(1) There were no significant correlation among gender, age, culture degree and cognitive dysfunction in stability after TBI.(2) The acute phase CT images, brain injury severity, GCS, plateau CT parameters of the third ventricle width(VR3) were associated with cognitive function after TBI.(3) P300 amplitude significantly reduced and latency prolonged in TBI group of frontal area of the central electrode than in the normal group. There were significant correlations among frontal area of the central electrode P3 a latency, intelligence, daily life and social life function in TBI group.(4) Amplitude of Mismatch negative significantly reduced of TBI group compared with healthy controls. MMN in FCz electrode correlated maximum with daily life function. MMN amplitude in Fz electrode had negative correlation with social function in TBI.Conclusion:(1) The gender, age and cultural degree not be considered as important factors of influenced cognitive function after TBI.(2) Cognitive dysfunction prognosis after TBI were related to computed tomography in the acute phase and stable phase and the degree of damage of TBI.(3) Forebrain area was pay attention to the processing and P3 a was significantly lower than the control group in frontal temporal lobe of TBI. P300 in frontal area of FZ electrode reflect cognitive dysfunction after TBI in stabilization, and P3 a latency is one of the most sensitive indicators.(4) MMN after TBI had significant statistical significance in predicting the cognitive and neural function prognosis, and in the frontal central MMN and functional outcomes was most relevant. MMN can efficiently reflect the function prognosis of TBI.