自身免疫性胰腺炎超声表现及与胰腺癌的鉴别

Ultrasonography manifestation and differential diagnosis of autoimmune pancreatitis

目的 探讨自身免疫性胰腺炎（autoimmune pancreatitis AIP）的超声及超声造影表现特征,以及与胰腺癌的鉴别诊断要点.方法 回顾性分析于我院诊断的16例AIP的常规超声和超声造影表现,并与32例胰腺癌比较.结果 16例AIP中11例（68.8％）常规超声表现为局灶性病变,5例（31.3％）表现为胰腺弥漫性肿大.32例胰腺癌常规超声均表现为胰腺低回声局灶性病变,未见全胰弥漫性病变.AIP中11例胆囊壁及胆管壁增厚,11例胆总管下端狭窄,8例脾大,与胰腺癌相比差异有统计学意义.而胰腺癌中18例血管侵犯,19例胰腺体尾部萎缩,28例胰管扩张.超声造影局灶性AIP增强早期呈低增强4例,等增强6例,高增强1例;增强晚期呈低增强4例,等增强7例.5例弥漫性AIP呈实质均匀低增强.胰腺癌增强早期呈低增强26例,等增强3例,高增强3例;增强晚期呈低增强31例,等增强1例.结论 AIP可表现为弥漫性或局灶性病变,而胰腺癌多为局灶性病变.超声造影有助于AIP与胰腺癌的鉴别,AIP的胰外表现较有特征性.

Objective To evaluate the imaging features of autoimmune pancreatitis （AIP） and differential diagnosis characteristic from pancreatic cancer on conventional ultrasound and contrast-enhanced ultrasound （CEUS）.Methods The imaging features of 16 AIP and 32 pancreatic cancer on conventional ultrasound and CEUS were analyzed and compared retrospectively.Results On conventional ultrasound 11 in 16 AIP cases （68.8 %） appeared as focal pancreatic lesions and 5 cases （31.3%） were diffuse lesions in whole pancreas.The thickening gallbladder wall and bile duct wall were 11 cases,distal common bile duct stenosis cases were 11 cases and splenomegaly were 8 cases,and both were the most out-pancreas changes.While in 32 cases of pancreatic cancer,all cases were hypo-echoic focal lesions.There were rare out-pancreas changes.The vascular invasion,pancreatic parenchyma atrophy and pancreatic duct dilatation were often detected in 18 cases,19 cases and 28 cases.In CEUS for focal AIP,hypo-enhancement,iso-enhancement and hyper-enhancement were 4 cases,6 cases,1 case in the early phase and 4 cases,7 cases,0 cases in the late phase.For 5 diffuse AIP cases homogeneous hypo-enhancement was the common enhancement pattern.For pancreatic cancer cases,hypo-enhancement,iso-enhancement and hyper-enhancement were 26 cases,3 cases,3 cases in the early phase and 31 cases,1 case,0 cases in the late phase.Conclusions AIP may manifest as diffuse or focal lesions whereas pancreatic cancers mainly appeared as focal lesions,CEUS is helpful in differential diagnosis of AIP from pancreatic cancer.AIP has the characteristic features outside the pancreas.