低场强磁共振弥散成像对早期脑缺血诊断价值的研究

Low Magnetic-field Intensity MR Diffusion-weighted Imaging(DWI) Incerebral Ischemia In Early Stage

目的：探讨低场强磁共振弥散成像对早期脑缺血的诊断价值。材料与方法：对48例不同时间段的脑缺血思者磁共振弥散加权成像（DWI）图像与平扫T1、WI、T2WI和FIR信号图像进行对比分析。结果：48例患者中，3例一过性脑缺血患者DWI无高信号出现；发病3小时内DWI出现稍高信号占33％，其他序列均无信号异变；3-6小时FTR和T2WI20％见高信号，DWI 60％见稍高信号；7-12小时T1 WI 22％见稍低信号，T2WI和FIR见高信号占89％，DWI见高信号占94％；13-24小时T1WI见低信号占71％，T2WI、FIR和DWI均见高信号占100％。结论：低场强磁共振弥做成像对早期脑缺血病变比平扫具有发现早、诊断可靠的特点。对临床治疗具有指导作用。

Purpose： To evaluate the value of low magnetic - field intensity MR diffusion- weighted imaging （DWI） incerebral ischemia in early stage. Materials and Methods： Compred 48 case of cerebral ischemia on DWI with T1 -weighted ;imaging （T1WI）. T2-weighted imaging （T2WI） and FIRin diffrent time. Results-Among forty-eight patients, threetranaient cerebral iachemia patient fotmd nohigh signal on DWI. Thrity-three percent high signal was seen on DWI and unural signal was not seen on other seauences within three hours. There are twenty percent high signal on FIR and T2WI, But sixty percent minimal high signal on DWI from three hours to six hours. Twenty - two percent minimal low signal was seenon T2WI from seven hours to twelve hours. In the same time, There are eighty-nine percent. high signal on T2 Wiand FIR and winty- four percent high signal on DWI. From thirteen to- twenty four hours, T1Wiwasseventy - one percent low signal T2WI, FIR and DWI are all high signal. Conclusion： Low magnetic - field intensity DWI is more sensitive than plain scan for detecting and diagnoting cerebral ischemia in early stage. It has a role of directing clinical treatment.