关键词: 磁敏感加权成像, 弥散张量成像, 磁共振, 重型弥漫性轴索损伤

Abstract: Objective Severe diffuse axonal injury(DAI) has a high rate of mortality and disability.Due to the limitations of conventional imaging techniques,condition assessment and prognosis still remain challenging.Susceptibility weighted imaging(SWI) and diffusion tensor imaging(DTI) can identify posttraumatic cerebral microbleeds and white matter fiber integrity.We utilized multiple MRI techniques to comprehensively assess the correlation between the extent of brain injury and prognosis.Methods Fifty patients with severe DAI from the Department of Neurosurgery,the First Affiliated Hospital of University of science and technology of China were included,and clinical data,scale assessment,and imaging data were collected.Software was used to segment the whole brain into five brain regions and extract the number,volume of microbleeds,and white matter fractional anisotropy(FA) .Analyze the correlation between the degree of brain damage and prognosis.Results The number and volume of microbleeds in the midline structural regions of the brain were correlated with FA values(P＜0.05),but not in other regions.The number and volume of microbleeds in the midsagittal region,brainstem,thalamus,and basal ganglia were positively correlated(P＜0.05) with the GCS score,GOS-6 and GOS-12 score;and negatively correlated correlated(P＜0.05) with the CRS-R score in patients with severe brain injury;Mean FA in brainstem,thalamus,and basal ganglia regions was positively correlated with GCS score,GOS-6 and GOS-12 score(P＜0.05);and negatively correlated with CRS-R score(P＜0.01) in patients with severe brain injury.Conclusion Microbleeds(SWI) and microstructural changes(DTI) in deep brain structures are pathological markers of post-traumatic brain injury,and the MRI indexes of SWI and DTI are of great significance for the evaluation of the extent of brain injury and for judging the prognosis.

Key words: SWI, DTI, MRI, Severe DAI