弥散加权MRI在超急性脑梗死诊断中的应用研究

目的:评估弥散加权MRI(DWI)对超急性脑梗死诊断的准确价值。方法:对临床高度怀疑超急性脑梗死且发病在6h以内的患者行急诊MRI和DWI检查。分析DWI诊断和最终临床诊断的相符性,比较DWI和常规MRI对超急性脑梗死敏感性和特异性、表观弥散系数(ADC)的时间变化规律。结果:DWI诊断超急性脑梗死20例,与最终临床诊断均符合。DWI所见高信号区域在CT/MRI随访中均有脑梗死灶。DWI诊断超急性脑梗死的敏感性和特异性均为100%,常规MRI的敏感性为20%,特异性为100%;超急性脑梗死DWI信号上升,ADC值下降(P<0.001)。结论:DWI可作为诊断超急性脑梗死的一项重要指标。

Application study of diffusion-weighted imaging MR in the diagnosis of hyperacute cerebral infarction

Objective: To evaluate the accuracy of diffusion-weighted imaging(DWI) MR in the diagnosis of hyperacute cerebral infarction. Materials and Methods: Those patients with onset of stroke-like symptoms that suggested a diagnosis of hyperacute cerebral infarction underwent conventional MRI and DWI within 6 hours. Analyses comprised the consistency of the initial DWI with the final clinical diagnosis- comparison of sensitivity and specificity of DWI with those of conventional MRI- to determine the time course of the apparent diffusion coefficient (ADC). Results: DWI defined hyperacute cerebral infarction in 20 patients- all of whom had a final diagnosis of acute stroke. The high signal showed on DWI was confirmed with CT MRI follow-up. DWI had a sensitivity and a specificity of 100% in the diagnosis of hyperacute cerebral infarction- and conventional MRI yielded a sensitivity and a specificity of 20% and 100% respectively. The signal of hyperacute cerebral infarction exhibited increased on DWI and decreased on ADC map. Conclusion: DWI is a significant method in the diagnosis of hyperacute cerebral infarction.