MRI弥散加权成像(DWI)诊断急性、亚急性脑梗塞及相关定量参数的应用

目的:总结我院2003～2004年间急性、亚急性脑梗塞病16例患者的MRI弥散加权成像(DW1)的表现,与 T2WI及T2WI FLAIR序列进行比较,并对感兴趣区进行ADC(表观弥散系数)值测量,推测梗塞灶的面积。方法:急性、亚急性脑梗塞病例16例,其中4例为4小时内检查发现,行急诊溶栓;8例为24小时内检查;2例为3天后一周内检查发现。临床表现12例为脑卒中症状,另外,1例为术后甲状腺危象患者抢救成功后检杳发现脑梗塞病灶,2例颈椎病症状、1例病人以急性心梗入院,入院后检查有亚急性脑梗塞灶。结果:诊断急性、亚急性梗塞病灶24个,基底节区5个,放射冠区4 个,半卵圆中心区2个,小脑半球3个,脑干4个,同时或分别累及颞顶枕叶共6例。其中5名患者为多次发生梗塞,通过 DWI确定责任病灶7个。在放射冠区、小脑、及枕叶病灶明显,基底节区部分病灶显示欠佳,可能与病灶面积较小有关。 T2WI发现病灶5个,T2WI Flair发现病灶6个。TIWI显示病灶数为0个,结论:DWI对诊断急性脑梗塞以及鉴别新旧脑梗塞、确定责任病灶上有较高价值;ADC值的测量对诊断及推断缺血区面积有参考意义;而不同b值(弥散梯度因子)对诊断没有明显的影响。

Acute and Subacute Brain Infarction Diagnosis with MRI Diffusion Weighted Image(DWI) and Application of Related Quantitative Parameters

Objective:We reviewed the patients with acute and subacute stroke who underwent MRI DWI (Diffusion-Weighted imaging) sequence with different "b" value (Diffusion Gradient Coefficient ) during 2003~2004, and compared them with the T2WI and T2WI FLAIR sequences, estimated the size of lesion through measuring ADC (Appearance Diffusion Coefficient) values around lesions. Methods: 16 subjects who were suspected stroke in clinic and then were confirmed with MRI, 4 of them were sent our hospital within 4 hours and were treated by thrombolytic therapy in emergency;8 of them in 24 hours and 2 of them in 72 hours;12 of them had obvious clinical manifestations of strokel thyroid crisis signs, 2 cervical spondylosis symptoms, 1 miocardial infarction indications,who were confirmed subacute infarction. Results: 24 lesions were found out as acute or subacute cerebral stroke with MRI, 7 duty lesions were differentiated from chronic lesions in repetitive infarction clients. Respectively, 5 of lesions in basal ganglia, and 4 in corona radiate area, 2 in centrum semiovale, 3 in cerebellum, 4 in brainstem, and 6 of them in temporal, parietal and occipital lobe respectively. Possibly due to the small size, few of lesions seem obscure in the basal ganglia. 5 lesions were identified with T2WI and more clearly in the T2WI FLAIR sequence. No lesion was found in T1WI, as indirectly signs. Conclusion: We can draw conclusions that DWI is an effective method for acute or subacute stroke diagnosis and differentiating the duty focus from the chronic lesions. Measuring the value of ADC around the lesions is helpful to estimating the size of the ischemic necrosis. No beneficial for diagnosis was found between different b values imagine.