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

摘要： 目的 重型弥漫性轴索损伤(DAI)具有较高的致死率和致残率。由于常规MRI成像技术的局限性,病情评估及预后判断仍具有挑战性。磁敏感加权成像(SWI)和弥散张量成像(DTI)可以识别创伤后脑微出血和白质纤维的完整性。我们利用多种MRI技术综合评估脑损伤程度与预后之间的相关性。方法 纳入中国科学技术大学附属第一医院(安徽省立医院)神经外科138例重型弥漫性轴索损伤患者,收集临床资料、量表评估及影像学资料。利用软件将全脑分割为五大脑区,提取微出血数量、体积和白质异向性(FA),统计分析与脑损伤程度与预后之间的相关性。结果 大脑中线结构区域的微出血数量和体积与FA值相关(P＜0.05),而其他区域无明显相关。正中矢状区、脑干、丘脑和基底神经节微出血的数量和体积与重度颅脑损伤患者的入院GCS评分、6个月和12个月后的GOS评分呈线性负相关(P＜0.05),与CRS-R评分呈线性正相关(P＜0.05);脑干、丘脑和基底神经节区域的平均FA与重度颅脑损伤患者的入院GCS评分、6个月和12个月后的GOS评分呈线性正相关(P＜0.05),与CRS-R评分呈线性负相关(P＜0.01)。结论 深部脑结构中微出血(SWI)和微观结构变化(DTI)是创伤后脑损伤的影像学标志物,SWI和DTI的MRI指标对脑损伤程度的评估及判断预后有着重要意义。

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