目的 分析磁共振弥散张量成像 (DTI)对急性脑梗死(ACI)患者早期诊断 及临床转归的预测价值。方法 回顾性收 集2017年9月-2018年6月期间我院收治的 80例单侧ACI患者的诊治、随访资料，其 中超急性期(发病时间＜6h)16例、急性 期(6-72h)38例、亚急性期(72h-14d)26 例，均接受MRI检查，包括常规序列、DTI 序列，至少随访3个月，依据美国国立卫 生研究院卒中量表(NIHSS)评分评估临床 转归情况。结果 80例ACI患者均可通过 常规MRI与DTI发现梗死病灶，病灶检出 率为100%。梗死灶在T2WI、DWI图像上均 显示高信号，DTI上以低信号为主。不同 发病时期患者病灶侧FA、DCavg值均低于 健侧(P＜0.05)；FA、DCavg值超急性期＞ 急性期例＞亚急性期，比较有统计学差 异(P＜0.05)。3个月后随访发现病灶区 FA、DCavg值下降率超急性期＜急性期例 ＜亚急性期，且NIHSS评分超急性期＜急 性期例＜亚急性期，比较均有统计学差异 (P＜0.05)。Pearson相关分析显示，ACI 患者病灶区FA、DCavg值下降率与NIHSS 评分呈明显正相关(r=0.465，0.524，P ＜0.05)。结论 DTI参数在不同发病时期 ACI患者中存在特定的改变规律，可作为 临床早期诊断依据，其中FA、DCavg值与 预后指标密切相关，有望用于预测临床转 归。

Objective To analyze the predictive value of diffusion tensor imaging (DTI) for the early diagnosis and clinical outcome in patients with acute cerebral infarction (ACI). Methods The clinical data and follow-up data of 80 patients with unilateral ACI in the hospital from September 2017 to June 2018 were collected retrospectively. There were hyperacute phase (onset time less than 6h) of 16 cases, the acute phase (6 to 72h) of 38 cases and the subacute phase (72h to 14d) of 26 cases, all of them were given MRI examination, including regular sequence, DTI sequence with at least 3 months of followup, clinical outcomes were assessed according to the National Institutes of Health Stroke Scale (NIHSS) score. Results A total of 80 patients with ACI could find the infarct lesions by conventional MRI and DTI with 100% detection rate. Infarcts lesions showed high signal on T2WI and DWI images, and mainly showed low signal on DTI. The FA and DCavg values of the lesions were lower than those of the healthy side (P<0.05). The FA and DCavg values at the lesion side of patients in different onset periods were lower than those at the healthy side. Arranging the FA and DCavg values from large to small, the order was hyperacute phase, acute phase and subacute phase (P<0.05). After 3 months of follow-up, it was found that arranging the reduction rate of FA and DCavg values in the lesion area from small to large, the order was super acute phase < acute phase < subacute phase, and NIHSS score was hyperacute phase, acute phase and subacute phase (P< 0.05). Pearson correlation analysis found that the decrease rate of FA and DCavg values in the lesion area of ACI patients was positively correlated with NIHSS score (r=0.465, 0.524, P<0.05). Conclusion DTI parameters have specific changes direction in ACI patients at different onset period, which can be used as a basis for clinical diagnosis. FA and DCavg values are closely related to prognostic indicators and has the potential to be used to predict the clinical outcomes.