【摘要】 目的:探讨磁共振弥散加权成像(DWI)表观扩散系数图(ADC图)在脑梗死分期中的价值。方法:对75例脑梗死患者共作了81例次(超急性期15例次、急性期15例次、亚急性期31例次、稳定期12例次及慢性期8例次)DWI及常规MRI检查。测定各期梗死灶ADC值及对侧ADC值,计算相对ADC(rADC),分析判断rADC在各期脑梗死中的演变情况。结果:超急性期、急性期及亚急性期梗死灶ADC值为(4.96±0.98)×10-4mm2/s,低于对侧相应区域(8.18±1.07)×10-4mm2/s。(t=2.22,P<0.05);rADC以超急性期最低,随时间延长由低到高,于8~14天出现假性正常化,于慢性期高于正常水平,rADC与时间具有相关性(rs=1.00,P<0.05)。结论:各期脑梗死灶ADC值具有特征性演变规律,结合DWI、T2WI对早期脑梗死的检出和准确分期具重要价值。更多还原

【Abstract】 Objective:To investigate the value of MR diffusion-weighted imaging（DWI） and apparent diffusion coefficients（ADC） mapping in defining the stage of cerebral infarction.Methods:81 work-up in 75 patients with cerebral infarction（15 hyperacute,15 acute,31 subacute,12 steady,and 8 chronic） were performed with both diffusion weihted imaging and conventional MRI scanning.The ADC in the infarct lesion and relative ADC（rADC） were calculated.Results:The ADC of cerebral ischemic regions of the hyperacute,acute,and subacute was lower than contralateral tissue(（4.96±0.98）×10^-4mm²/s versus（8.18±1.07）×10^-4mm²/s,t=2.22,P<0.05)).rADC of hyperacute was minimized,and increased progressively as time passed and appeared as "pseudonormal" values in 8 to 14 days.Thereafter,rADC became greater than normal in chronic stage.There was positive correlation between rADC and time（r_s=1.00,P<0.05）.Conclusion:ADC values have specific evolving rule on ADC mapping.Combined with DWI and T₂WI,ADC values can diagnose early stage cerebral infarction and differentiate different stages of infarction.更多还原