弥散加权成像不同b值对急性脑梗死ADC变化趋势的分析

Preliminary study on change trends of apparent diffusion coefficient under different b values of diffusion-weighted imaging in acute cerebral infarction

目的探讨急性脑梗死患者弥散加权成像(DWI)不同b值下表观弥散系数(ADC)值的变化趋势。方法选取急性脑梗死患者为病例组,健康志愿者为对照组,使用5个不同的弥散梯度,即b=200、400、600、800、1 000s/mm2对20例急性脑梗死患者及20例健康志愿者进行DWI扫描,测量不同b值下的ADC值。使用单因素方差分析对两组ADC值进行统计学分析。结果在5个不同b值下,病例组ADC值分别为0.64、0.59、0.55、0.47、0.41,对照组ADC值分别为1.04、0.99、0.92、0.85、0.78;两组差异具有统计学意义(P<0.01),且随着b值升高,ADC值具有降低趋势(P<0.01)。结论急性脑梗死患者ADC值明显降低;DWI不同b值下ADC值不同,二者呈负相关。

Objective To investigate the change trends of apparent diffusion coefficient（ADC） values under different b values of diffusion-weighted imaging（DWI） in acute cerebral infarction. Methods The patients with acute celebral infarction were selected as the experimental group and the normal volunteers as the control group. The 5 different diffusion gradients were used,including b =200 s/mm^2 ,b=400 s/mm^2 ,b=600 s/mm^2 ,b=800 s/mm^2 and b=1 000 s/mm^2. The two pairs of 20 cases of acute cerebral infarction and 20 healthy volunteers were performed the DWI scanning for detecting the ADC value under different b values. The ADC values in the two groups were statistically analyzed by using one-way anova. Results In 5 different b values, the ADC values in the case group was 0. 64,0. 59,0.55,0. 47 and 0. 41 respectively, which in the control group were 1.04,0. 99,0.92,0. 85 and 0.78 respectively, the differences between the two groups were statistically significant, moreover with the b value increase, the ADC value had a decreasing trend（P〈0. 01）. Concision The ADC value in the patients with acute cerebral infarction is significantly decreased, the ADC values are different under different b values of DWI,morepver which shows the significantly negative correlation trend.