Rezvani Maryam, Menias Christine, Sandrasegaran Kumaresan, Olpin Jeffrey D, Elsayes Khaled M, Shaaban Akram M
From the Department of Radiology, University of Utah, 30 North 1900 East, #1A71, Salt Lake City, UT 84132 (M.R., J.D.O., A.M.S.); Department of Radiology, Mayo Clinic, Scottsdale, Ariz (C.M.); Department of Radiology, Indiana University School of Medicine, Indianapolis, Ind (K.S.); and Department of Radiology, MD Anderson Cancer Center, Houston, Tex (K.M.E.).
Radiographics. 2017 Mar-Apr;37(2):484-499. doi: 10.1148/rg.2017160091.
Heterotopic pancreas is a congenital anomaly in which pancreatic tissue is anatomically separate from the main gland. The most common locations of this displacement include the upper gastrointestinal tract-specifically, the stomach, duodenum, and proximal jejunum. Less common sites are the esophagus, ileum, Meckel diverticulum, biliary tree, mesentery, and spleen. Uncomplicated heterotopic pancreas is typically asymptomatic, with the lesion being discovered incidentally during an unrelated surgery, during an imaging examination, or at autopsy. The most common computed tomographic appearance of heterotopic pancreas is that of a small oval intramural mass with microlobulated margins and an endoluminal growth pattern. The attenuation and enhancement characteristics of these lesions parallel their histologic composition. Acinus-dominant lesions demonstrate avid homogeneous enhancement after intravenous contrast material administration, whereas duct-dominant lesions are hypovascular and heterogeneous. At magnetic resonance imaging, the heterotopic pancreas is isointense to the orthotopic pancreas, with characteristic T1 hyperintensity and early avid enhancement after intravenous gadolinium-based contrast material administration. Heterotopic pancreatic tissue has a rudimentary ductal system in which an orifice is sometimes visible at imaging as a central umbilication of the lesion. Complications of heterotopic pancreas include pancreatitis, pseudocyst formation, malignant degeneration, gastrointestinal bleeding, bowel obstruction, and intussusception. Certain complications may be erroneously diagnosed as malignancy. Paraduodenal pancreatitis is thought to be due to cystic degeneration of heterotopic pancreatic tissue in the medial wall of the duodenum. Recognizing the characteristic imaging features of heterotopic pancreas aids in differentiating it from cancer and thus in avoiding unnecessary surgery. RSNA, 2017.
异位胰腺是一种先天性异常，其中胰腺组织在解剖学上与主腺体分离。这种移位最常见的部位包括上消化道，特别是胃、十二指肠和空肠近端。较不常见的部位是食管、回肠、梅克尔憩室、胆道系统、肠系膜和脾脏。无并发症的异位胰腺通常无症状，病变在无关手术、影像学检查或尸检时偶然发现。异位胰腺最常见的计算机断层扫描表现是壁内小椭圆形肿块，边缘呈微分叶状，呈腔内生长模式。这些病变的衰减和强化特征与其组织学组成平行。以腺泡为主的病变在静脉注射对比剂后表现为明显均匀强化，而以导管为主的病变则血供较少且不均匀。在磁共振成像中，异位胰腺与正常胰腺等信号，在静脉注射钆基对比剂后具有特征性的T1高信号和早期明显强化。异位胰腺组织有一个基本的导管系统，在影像学上有时可见一个小孔，表现为病变的中央凹陷。异位胰腺的并发症包括胰腺炎、假性囊肿形成、恶性变、胃肠道出血、肠梗阻和肠套叠。某些并发症可能被误诊为恶性肿瘤。十二指肠旁胰腺炎被认为是由于十二指肠内侧壁异位胰腺组织的囊性变所致。认识异位胰腺的特征性影像学表现有助于将其与癌症区分开来，从而避免不必要的手术。RSNA，2017年。
