沟槽区胰腺炎多层螺旋CT征象分析

目的:探讨沟槽区胰腺炎的MSCT征象,提高对该病的影像学诊断水平.方法:回顾性分析53例GP患者的临床及CT影像学资料,所有病例经手术病理或ERCP活检病理证实.观察沟槽区肿块或囊状病变的强化特点和分型,以及邻近结构的影像学改变.结果:53例的主要CT表现:①均可见沟槽区软组织增厚改变,CT平扫呈等或混杂稍低密度,动脉期呈轻度强化或无强化,实质期呈渐进性不均匀延迟强化;②57％(30/53)伴有副胰管开口邻近十二指肠降部肠壁或胰头实质的囊性变(长径10～48 mm);③十二指肠降部肠壁增厚45例(85％),其中40例为弥漫性水肿,5例为局部性水肿;④胰管扩张占19％(10/53),胆总管扩张占15％(8/53);⑤其它:沟槽区积液占89％(47/53),淋巴结炎(短径8～17 mm)占23％(12/53).结论:沟槽区胰腺炎的MSCT征象具有一定特征性,双期增强扫描对本病的诊断具有重要价值.     

Revisión de la pancreatitis del surco y cómo diferenciarla del adenocarcinoma de páncreas

Groove pancreatitis is an uncommon type of chronic pancreatitis that affects the space between the head of the pancreas, the second portion of the duodenum, and the common bile duct. The main trigger is chronic alcohol abuse, which eventually leads to leakage of pancreatic juices into the pancreaticoduodenal groove, causing inflammation and fibrosis. The main differential diagnosis is with pancreatic adenocarcinoma, which is more common than groove pancreatitis.Different imaging techniques make it possible to identify various findings (e.g., duodenal thickening or duodenal and paraduodenal cysts, which are characteristic of groove pancreatitis) that sometimes enable differentiation between groove pancreatitis and other entities, although there are no specific findings for each of them. Sometimes biopsy or surgery is required to establish the definitive diagnosis.The treatment of groove pancreatitis is usually conservative, but in cases in which the symptoms do not improve, interventional procedures (biliary drainage) or surgery (Whipple technique) can be done.     

Groove pancreatic carcinomas: radiological and pathological findings

The aim of this study was to clarify the characteristics of pancreatic head carcinomas mainly invading the groove between the duodenum and the pancreatic head. Nine patients with pathologically proven pancreatic head carcinomas underwent thin-slice dynamic CT, MR imaging, duodenal endoscopy, and angiography (seven patients). Plate-like masses within the groove region were seen in all cases, which showed hypointensity on T1-weighted images and slight hyperintensity on T2-weighted MR images. The masses appeared hypovascular in the early phase and delayed enhancement in the late phase of dynamic CT and MR imaging. On MR cholangiopancreatography, stenosis of intrapancreatic common bile duct was seen in all patients, whereas stenosis of the main pancreatic duct was seen in only three cases. Endoscopy revealed luminal narrowing of the duodenum in all patients, and duodenal mucosal biopsy demonstrated adenocarcinoma in seven patients. Abdominal arteriography showed serrated encasement of peripancreatic arteries in seven patients who received angiographic examinations. The CT and MR imaging findings of groove pancreatic carcinomas resemble those of groove pancreatitis. Differential diagnosis may be achieved by the pathological diagnosis of a biopsy specimen of the duodenal mucosa and arterial encasement on arteriography.     

Differential diagnosis of periampullary carcinomas at MR imaging.

Periampullary carcinomas arise within 2 cm of the major duodenal papilla and comprise carcinomas of the ampulla, distal common bile duct, pancreas, and duodenum. Their clinical features and anatomic locations are similar, as are the therapeutic approaches; however, their long-term outcomes vary. Magnetic resonance (MR) images of 89 pathologically proved periampullary carcinomas (29 ampullary carcinomas, 27 distal common bile duct carcinomas, 21 pancreatic carcinomas, six duodenal carcinomas, and six unclassified carcinomas) were reviewed. Ampullary carcinoma manifests as a small mass, periductal thickening, or bulging of the duodenal papilla. Pancreatic carcinoma is characterized by a discrete parenchymal mass, which enhances poorly on dynamic gadolinium-enhanced images. Sometimes, two proximal and two distal pancreatic and biliary ducts appear as four separate ducts (the four-segment sign). Dilatation of side branches of the pancreatic ducts is frequently seen in pancreatic carcinoma but not in other periampullary carcinomas. Distal bile duct carcinoma manifests as luminal obliteration and wall thickening or as an intraductal polypoid mass. A dilated proximal bile duct, a nondilated distal bile duct, and a dilated or nondilated pancreatic duct may form the three-segment sign. MR cholangiopancreatography and sectional MR imaging are useful in determining the origins of periampullary carcinomas.     

自身免疫性胰腺炎多种影像学比较分析

目的 探讨多种影像学检查对自身免疫性胰腺炎(AIP)的诊断价值.方法 回顾性分析我院2008年4月至2011年12月17例AIP患者的临床及影像学资料,男性13例,女性4例,年龄48～68岁,17例均行CT平扫及增强扫描;12例行磁共振成像(MRI)及磁共振胰胆管造影(MRCP)检查,9例行经内镜逆行胰胆管造影(ERCP)检查且7例同时行胆总管支架置入术.结果 CT、MRI既可以显示胰腺形态改变;也可以发现胰腺周围结构改变,而MRCP和ERCP可显示胰胆管结构改变.结论 自身免疫性胰腺炎影像学表现具有一定的特征性,结合多种影像学检查早期诊断和治疗对预后有重要意义.     

Complications of endoscopic retrograde cholangiopancreatography: spectrum of abnormalities demonstrated with CT.

Endoscopic retrograde cholangiopancreatography (ERCP) is an invasive procedure that is performed to diagnose and treat pancreatic and biliary disease. In approximately 5%-10% of cases, the procedure itself causes adverse events. Diagnosis and management of ERCP-induced complications are performed with clinical, laboratory, and radiologic procedures. Evaluation of the type and severity of the complication is necessary and is successfully performed with computed tomography (CT). The most common causes of post-ERCP pain are acute pancreatitis and duodenal perforation. In severe pancreatitis, the pancreas is enlarged and enhances heterogeneously at CT. Pancreatic enhancement is diminished in areas of glandular necrosis. In duodenal perforation, CT may reveal extraluminal air or fluid. CT findings of acute duodenal hemorrhage are duodenal wall thickening and a high-attenuation mass in the duodenal wall. In infection, the bile ducts can be dilated and the attenuation of the bile can be increased at CT. Abscesses appear as hypoattenuating masses with enhancing capsules. CT findings of stent migration are an atypical location of the stent and bowel impaction. Other complications of ERCP are those related to endoscopy and include esophageal, liver, and splenic injury.     

Dual-phase CT findings of groove pancreatitis

Purpose

Groove pancreatitis is a rare focal form of chronic pancreatitis that occurs in the pancreaticoduodenal groove between the major and minor papillae, duodenum and pancreatic head. Radiologic appearance and clinical presentation can result in suspicion of malignancy rendering pancreaticoduodenectomy inevitable. This study reports dual phase CT findings in a series of 12 patients with pathology proven groove pancreatitis.

Materials and methods

Retrospective review of preoperative CT findings in 12 patients with histologically proven groove pancreatitis after pancreaticoduodenectomy. Size, location, attenuation, presence of mass or cystic components in the pancreas, groove and duodenum, calcifications, duodenal stenosis and ductal changes were recorded. Clinical data, laboratory values, endoscopic ultrasonographic and histopathological findings were collected.

Results

Soft tissue thickening in the groove was seen in all patients. Pancreatic head, groove and duodenum were all involved in 75% patients. A discrete lesion in the pancreatic head was seen in half of the patients, most of which appeared hypodense on both arterial and venous phases. Cystic changes in pancreatic head were seen in 75% patients. Duodenal involvement was seen in 92% patients including wall thickening and cyst formation. The main pancreatic duct was dilated in 7 patients, with an abrupt cut off in 3 and a smooth tapering stricture in 4. Five patients had evidence of chronic pancreatitis with parenchymal calcifications.

Conclusion

Presence of mass or soft tissue thickening in the groove with cystic duodenal thickening is highly suggestive of groove pancreatitis. Recognizing common radiological features may help in diagnosis and reduce suspicion of malignancy.     

Pancreas. Congenital changes, acute and chronic pancreatitis

The pancreas develops from ventral and dorsal buds, which undergo fusion. Failure to fuse results in pancreas divisum, which is defined by separate pancreatic ductal systems draining into the duodenum. Risk of developing pancreatitis is increased in pancreas divisum. MR cholangiopancreatography (MRCP) is the technique of choice for detecting it non-invasively. Annular pancreas is the result of incomplete rotation of the pancreatic bud around the duodenum with the persistence of parenchyma or a fibrous band encircling (stenosing) the duodenum. Acute pancreatitis is usually caused by bile duct stones or alcohol abuse. Contrast-enhanced multi-detector row CT is the method of choice to assess the extent of this disease. In acute pancreatitis, the role of MRCP is mainly limited to finding bile duct stones in patients with suspected biliary pancreatitis. Chronic pancreatitis results in relentless and irreversible loss of exocrine (and sometimes endocrine) function of the pancreas. MDCT even shows subtle calcifications. MRCP is the method of choice for non-invasive assessment of the duct. Inflammatory pseudotumor in chronic pancreatitis and groove pancreatitis are difficult to differentiate from pancreatic cancer. In these cases, multiple imaging methods such as MDCT, MRI and endosonography including biopsy may be used to make a diagnosis.     

CT of the extrahepatic bile ducts: wall thickness and contrast enhancement in normal and abnormal ducts

Recent reports have described thickening and enhancement of the extrahepatic bile duct wall on CT scans obtained after administration of IV contrast material. We undertook this study to establish parameters for the normal thickness and enhancement of the bile duct wall on CT, and to develop a differential diagnosis for thickening of the duct wall. Routine CT examinations of 100 patients without biliary disease were evaluated prospectively. The common hepatic duct and common bile duct could be visualized in 66% and 82% of cases, respectively; the walls of these ducts could be separately discerned in 59% and 52%. The mean thickness of the duct wall was 1 mm, with a maximal thickness of 1.5 mm. Wall enhancement was similar to (51%), slightly greater than (44%), or markedly greater than (5%) the enhancement of adjacent pancreatic parenchyma. A review of records covering a 5-year period identified 52 patients in whom CT showed thickening of the bile duct wall (greater than or equal to 2 mm). These patients could be categorized by seven underlying diseases, and analysis of the CT scans revealed four general patterns of thickening. Focal, concentric wall thickening in the distal common bile duct was associated with pancreatitis, pancreatic cancer, and common bile duct stones; focal, eccentric thickening tended to occur with cholangiocarcinoma and sclerosing cholangitis. Diffuse, concentric thickening was seen with acute cholangitis; diffuse, eccentric thickening was associated with oriental cholangiohepatitis and sclerosing cholangitis. Thickening of greater than 5 mm was seen only with cholangiocarcinoma. Enhancement of the duct wall in these groups varied and was of no predictive value. In summary, the extrahepatic bile ducts can be visualized in the majority of patients, and the normal duct wall should be 1.5 mm or less in thickness. Contrast enhancement of the duct wall occurs in patients without biliary tract disease and alone is predictive not predictive of pathology. Pancreatitis, pancreatic cancer, common bile duct stones, cholangiocarcinoma, sclerosing cholangitis, acute cholangitis, and oriental cholangiohepatitis are associated with thickening of the duct wall.     

Imaging Features of Adult Choledochal Cysts: a Pictorial Review

Choledochal cysts are rare congenital anomalies which are principally diagnosed by disproportional dilatation of the extrahepatic bile ducts. In addition, choledochal cysts are believed to arise from the anomalous union of the common bile duct and pancreatic duct outside the duodenal wall which is also proximal to the sphincter of the Oddi mechanism. The various types of choledochal cysts have been classified on the basis of these anomalous unions (Komi classification) and their anatomical locations (Todani classification). The multidetector computed tomography with reformatted imaging, magnetic resonance cholangiopancreatography, and an endoscopic retrograde cholangiography represent the important techniques providing the anatomical resolution and detail required to properly diagnose and classify choledochal cysts and their associated abnormal features of the biliary tree, as well as their pancreaticobile duct union. This study describes the various imaging features of a choledochal cyst in adults according to the various types of anomalous unions of the pancreaticobile duct according to Komi''s classification and anatomic location according to Todani''s classification. Lastly, we also review and discuss the associated abnormal findings developed in biliary systems.     

Imaging of the biliary sump syndrome.

Side-to-side choledochoduodenostomy is a safe and effective surgical technique to improve biliary drainage in selected patients. The segment of common bile duct between the anastomosis and the ampulla of Vater may act as a stagnant reservoir or sump. When debris, stones, or infected bile accumulates in the sump, usually because of malfunction of the ampulla of Vater, recurrent abdominal pain or symptoms of cholangitis, pancreatitis, or biliary obstruction may develop. This uncommon (0.14-1.30%) complication is known as the sump syndrome. On imaging studies, diagnostic findings are debris or stone(s) in the common bile duct. Suggestive findings are dilated bile or pancreatic ducts, and changes due to pancreatitis, cholangitis, or liver abscess. Patients with this syndrome frequently have multiple imaging studies before the condition is recognized. The purpose of this essay is to illustrate the imaging findings of this syndrome.     

自身免疫性胰腺炎病例分析并文献复习

目的 分析自身免疫性胰腺炎(autoimmune pancreatitis,AIP)的临床特点及诊疗措施.方法回顾分析1例AlP患者的临床表现、实验室检查、影像学检查、治疗及随访情况.结果 本病例结合临床表现,血清IgG、γ球蛋白增高,正电子发射体层摄影术/计算机体层摄影术(PET/CT)、磁共振胰胆管造影术(mag...     

胰胆管十二指肠连接区癌的螺旋CT的表现

目的探讨胰胆管十二指肠连接区(PDDU)的解剖及连接区癌的病理、CT表现特点与扫描方法。方法对52例经病理证实为PDDU癌的临床及CT图像资料进行回顾性分析。结果螺旋CT诊断PDDU癌47例(乳头型32例,管腔内型13例,混合型2例);主要表现为软组织肿块,十二指肠腔内充盈缺损及局部黏膜破坏和肝内外胆管、胰管、胆总管扩张;5例因扫描方法不当致漏诊、误诊。结论螺旋CT能清晰显示PDDU癌的直接及间接征象,是一种很好的无创伤性检查方法,但正确的扫描方法是提高诊断率的前提条件。     

IgG4相关性疾病累及腹部组织器官的影像学表现

目的：探讨IgG4相关性疾病累及腹部组织器官的影像学表现。方法回顾性分析24例经病理证实或肾上腺皮质激素规范治疗后随访证实的IgG4相关性疾病累及腹部患者的临床资料,其中14例行CT检查,10例行MR检查,7例同时行CT及MR检查,分析其影像表现特征。结果①24例患者中9例确诊为自身免疫性胰腺炎,6例胰腺呈弥漫性肿大;2例呈局限性肿大;1例呈混合性肿大。CT平扫呈低密度;MRI T1WI信号均匀或稍不均匀降低,T2WI信号均匀或稍不均匀升高,增强后均匀渐进性延迟强化,假包膜征象显示完整;②6例为IgG4相关性胆管炎,表现为长且连续性的胆道狭窄,狭窄上段胆道常可见扩张,累及的胆道壁呈对称性的环周增厚、强化;③4例为IgG4相关性肾病,CT表现为肾实质内小类圆形、楔形或不规则低密度结节、肿块;增强扫描病灶呈相对低强化;④3例为腹膜后纤维化,表现为腹膜后不规则软组织病变,边界模糊,于CT平扫近似于肌肉密度,T1WI大多呈低信号,T2WI呈等信号,增强扫描强化不明显,部分可见轻度延迟强化;⑤1例同时累及胰腺及胆总管,表现为胰腺弥漫性肿大,增强扫描呈轻度渐进性强化。肝内外胆管扩张伴胰腺段胆总管不规则狭窄;⑥1例同时累及胰腺、胆总管及肾脏,表现为胰头局限性肿大、胆总管狭窄的同时双肾实质可见多发低密度结节。结论IgG4相关性疾病患者腹部组织器官受累具有特征性的CT和MRI表现,有助于明确诊断。     

MR cholangiopancreatography versus endoscopic sonography in suspected common bile duct lithiasis: a prospective, comparative study

OBJECTIVE: Our purpose was to compare the accuracy of MR cholangiopancreatography and endoscopic sonography for the diagnosis of common bile duct stones in patients with a mild to moderate clinical suspicion of common bile duct stones. SUBJECTS AND METHODS: Forty-seven patients were prospectively enrolled. Inclusion criteria included acute pancreatitis, subclinical jaundice, and clinical features of common bile duct stone migration. Radial endoscopic sonography and MR cholangiopancreatography with the single-shot fast spin-echo technique were performed a maximum of 48 hr apart. The gold-standard diagnosis was obtained with ERCP (n = 20) or intraoperative cholangiography (n = 14) if the results of endoscopic sonography or MR cholangiopancreatography were abnormal or if a cholecystectomy was performed, or by clinical and biochemical follow-up (n = 11) if the results of endoscopic sonography and MR cholangiopancreatography were normal. RESULTS: The final diagnosis was common bile duct stones in 16 patients, malignant obstructions in four, and another biliary disease in two (lithiasis migration aspect with papillary edema); 23 patients had no biliary disease. The sensitivity and specificity of MR cholangiopancreatography were, respectively, 90.5% and 87.5% for etiologic diagnosis and 87.5% and 96.6% for the detection of common bile duct stones. The corresponding values for endoscopic sonography were 86.4% and 91.3% for etiologic diagnosis and 93.8% and 96.6% for visualization of choledocholithiasis. Accuracy did not significantly differ between the techniques. CONCLUSION: In cases of mild to moderate suspicion of choledocholithiasis, the accuracies of endoscopic sonography and MR cholangiopancreatography are similar. Because MR cholangiopancreatography is noninvasive, it may be preferred for this indication.     

Juxtapapillary diverticulum: findings on CT and MRI

The purpose of this study was to evaluate the computed tomography (CT) and magnetic resonance imaging (MRI) features of juxtapapillary diverticulum. CT and/or MRI examinations of 12 patients were evaluated. The size, location of the diverticula and imaging findings of associated pancreaticobiliary disease were assessed. On CT, oral contrast air level was the characteristic imaging feature. On MRI, T2-weighted images demonstrated the air fluid level with hyperintense fluid and signal void air level above. Associated imaging findings were dilated common bile duct (CBD), cholecystitis, cholecystolithiasis and chronic pancreatitis.     

十二指肠乳头旁憩室伴胆胰疾病CT及MRI诊断

目的:探讨十二指肠乳头旁憩室伴胆胰疾病的CT和MRI诊断价值。方法:回顾性分析25例经临床随访证实的十二指肠乳头旁憩室伴胆胰疾病的CT和MRI表现,其中21例行CT平扫及增强,9例行MRI平扫、增强以及MRCP。结果:十二指肠乳头旁憩室CT及MRI表现壶腹周围含液气囊性病灶。MRCP表现为十二指肠内侧间壶腹部突出高信号囊性病灶。25例患者中合并胆胰病变CT和/或MRI表现为胆总管及肝内胆管结石13例,胆管扩张及壁增厚强化8例,胰腺肿胀3例,胰周脂肪层模糊4例及渗出2例,肾前筋膜增厚5例,胰管串珠样扩张2例。结论:CT及MR能显示十二指肠乳头旁憩室同时显示胆胰疾病引起胆管及胰腺形态学改变,有助于十二指肠乳头旁憩室伴胆胰疾病诊断。     

Role of MR cholangiopancreatography in patients with failed or inadequate ERCP

OBJECTIVE: The purpose of this study was to evaluate the spectrum of MR imaging features of primary sclerosing cholangitis. MATERIALS AND METHODS: A retrospective review was performed of MR imaging findings including MR cholangiography and multiphasic contrast-enhanced dynamic sequences in 22 patients with primary sclerosing cholangitis. MR imaging analysis included abnormalities of intra- and extrahepatic bile ducts, abnormalities of liver parenchyma, changes in liver morphology, and lymphadenopathy. RESULTS: Abnormal findings of bile ducts were seen in all 22 patients; the most common finding was intrahepatic bile duct dilatation (77%), followed by intrahepatic bile duct stenosis (64%), extrahepatic bile duct wall enhancement (67%), extrahepatic bile duct wall thickening (50%), extrahepatic bile duct stenosis (50%), and intrahepatic bile duct beading (36%). Increased enhancement of the liver parenchyma on dynamic arterial-phase images, predominantly in the peripheral areas of the liver, was identified in 56% of patients. Other findings included periportal lymphadenopathy (77%), periportal high signal intensity on T2-weighted images (68%), hypertrophy of the caudate lobe (68%), and abnormal hyperintensity of the liver parenchyma on T1-weighted images (23%). CONCLUSION: On MR imaging, primary sclerosing cholangitis showed several characteristic features, including bile duct abnormalities and increased enhancement of the liver parenchyma. MR cholangiography and contrast-enhanced dynamic MR techniques are useful for revealing intra- and extrahepatic signs of primary sclerosing cholangitis.     

Pankreas — Teil I

The pancreas develops from ventral and the dorsal buds, which undergo fusion. Failure to fuse results in pancreas divisum, which is defined by separate pancreatic ductal systems draining into the duodenum. Risk of developing pancreatitis is increased in pancreas divisum because of insufficient drainage. MR cholangiopancreatography (MRCP) is the technique of choice for detecting pancreas divisum non-invasively. Annular pancreas is the result of incomplete rotation of the pancreatic bud around the duodenum with the persistence of parenchyma or a fibrous band encircling (and sometimes stenosing) the duodenum. Acute pancreatitis is usually caused by bile duct stones or alcohol abuse. The Atlanta classification differentiates between mild acute and severe acute pancreatitis associated with organ failure and/or local complications such as necrosis, abscess or pseudocyst. Contrast-enhanced multi-detector row CT is the method of choice to assess the extent of disease. Balthazar et al.’s CT severity index assesses the risk of mortality and morbidity. In acute pancreatitis, the role of MRCP is mainly limited to finding bile duct stones in patients with suspected biliary pancreatitis. Chronic pancreatitis results in relentless and irreversible loss of exocrine (and sometimes endocrine) function of the pancreas. MDCT even shows subtle calcifications. MRCP is the method of choice for non-invasive assessment of the duct. Inflammatory pseudotumor in chronic pancreatitis and groove pancreatitis are difficult to differentiate from pancreatic cancer. In these cases, multiple imaging methods such as MDCT, MRI and endosonography including biopsy may be used to make a diagnosis.