壶腹癌的MRI诊断

Diagnosis of carcinoma in Vater's ampulla using MRI

目的探讨MRI尤其是肝脏三维容积超快速多期动态增强扫描(PropellerLAVA)在壶腹癌诊断中的价值。方法回顾性分析我院经手术病理证实的15例壶腹癌患者临床和影像学资料。所有病例手术前行常规MR扫描,PropellerLAVA序列动态增强扫描。MRCP采用最大强度投影(MIP)和多层面重建(MPR),在PropellerLAVA源图像观察肿瘤强化,MPR重建像观察胆总管及十二指肠腔内病变显示情况。结果胆总管梗阻端MRCP表现:①截断状5例;②腔内充盈缺损2例;③漏斗状或环形狭窄6例;④十二指肠腔内充盈缺损3例。动态增强表现:①动脉期至平衡期表现为轻度至中度逐渐明显异常强化7例;②平衡期轻度强化2例;③8～10min后延迟强化3例;④无明显强化3例。单纯采用MRCP判断肿瘤侵犯范围与手术病理相符13例,PropellerLAVA12例,两者结合15例。结论PropellerLAVA结合MRCP有利于壶腹癌病灶范围的观察及管腔内病变的显示,动态增强扫描MPR重建图像对肿瘤向管腔内侵犯显示更直观。

Objective To evaluate role of propeller liver acquisition with volume acceleration(LAVA)sequence with dynamic enhancement,on Upper-Abdomen scan,in diagnosing carcinoma in Vater's ampulla.Methods 15 patients who were confirmed as carcinoma in Vater's ampulla by surgical pathology were reviewed with their clinical and image data.All 15 cases underwent routine MRI scan and dynamics enhanced scan with Propeller LAVA sequence before operation.MRCP adopted maximum intensity projection(MIP)and multiple planar reformation(MPR).Enhancement of carcinoma was observed on Propeller LAVA.Lesions in common bile duct and duodenum lumen were observed with MPR.Results MRCP manifestations on obstructed end of common bile duct:truncated shape was found in 5 cases;lumen filling defect 2;funnel shape or ring-like narrowness 6;filling defect in the duodenum lumen 3.Manifestations on dynamic enhancement scan:mild to moderate abnormal enhancement was found in 7 cases during arterial phase to balanced phase,mild enhancement in 2 during balanced phase;delayed enhancement in 3 about 8~10 minutes after administration of contrast and no marked enhancement in 3.MRCP alone and surgical pathology were concordant in 13 cases in detecting tumor invasion area,the counterpart data for Propeller LAVA was 12,and for a combined use of MRCP and Propeller LAVA was 15.Conclusion A combined use of Propeller LAVA and MRCP is helpful for demonstrating invasion area of carcinoma and lesions in lumen.Dynamic enhancement scan with MRP reconstruc-tion can more directly demonstrate the carcinoma invasion into the duodenum lumen.