MRI-DWI对胰腺癌冻切术后治疗效果的鉴别诊断价值分析

目的 探讨磁共振弥散加权成像（MRI-DWI）对胰腺癌冻切术后治疗效果的鉴别诊断价值分析。方法 选取2015年6月～2018年6月病理诊断为胰腺癌并接受氩氦刀冷冻治疗的患者20例为研究对象，进行MRI-DWI检查扫描，观察胰腺癌肿瘤组织在冷冻术前后MRI-DWI信号改变，对比正常胰腺组织、术前及术后肿瘤组织、坏死组织的表现弥散系数（ADC）值。对肿瘤组织ADC值与肿瘤大小的相关性进行评价，同时评估不同肿瘤位置、肿瘤直径及分期ADC值的差异。结果 术后肿瘤组织在T_1WI呈低信号而在T_2WI为高信号，在DWI反而也是低信号，动态增强时没有明显强化。b值取800 s/mm~2时，正常胰腺组织和胰腺肿瘤的ADC值分别是（1.914±0.113）×10~3mm~2/s和（1.037±0.105）×10~(3 )mm~2/s。经对比发现胰腺肿瘤ADC值与肿瘤不同直径范围有关，与肿瘤分期、位置无关。结论MRI-DWI能有效鉴别胰腺癌切冻术后的肿瘤组织坏死及残存，为进一步临床诊治提供依据。

The value of MRI-DWI in differential diagnosis of treatment effect in pancreatic cancer after cryotherapy

Objective To investigate the value of magnetic resonance diffusion-weighted imaging(MRI-DWI)in the differential diagnosis of treatment effect in pancreatic cancer after cryotherapy.Methods Twenty patients with pathological diagnosis of pancreatic cancer who underwent argon-helium cryoablation from June 2015 to June 2018 were enrolled in the study.They were treated with MRI-DWI scan.The MRI-DWI signal changes of pancreatic cancer tissues before and after cryotherapy were observed.The apparent diffusion confficient(ADC)of normal pancreatic tissue,preoperative and postoperative tumor tissue,necrotic tissue were compared.The correlation between tumor tissue ADC value and tumor size was evaluated,and the differences in ADC values of different tumor location,tumor diameter,and staging were evaluated.Results Postoperative tumor tissue showed low signal on T1WI and high signal on T2WI,but also low signal on DWI.There was no obvious enhancement when dynamic enhancement.When the b value was 800 s/mm2,the ADC values of normal pancreatic tissue and pancreatic tumor were(1.914±0.113)×103 mm2/s and(1.037±0.105)×103 mm2/s,respectively.It was found that the ADC value of pancreatic tumor was related to tumor size and tumor diameter range,and was not related to tumor stage and location.Conclusion MRI-DWI can effectively identify tumor tissue necrosis and residual after pancreatic cancer cryotherapy,which provides a basis for further clinical diagnosis and treatment.