自身免疫性胰腺炎MRI表现

目的 探讨自身免疫性胰腺炎(AIP)的MRI表现.方法 回顾性分析经组织学和(或)类固醇激素治疗证实的11例AIP患者的MRI资料.结果 9例AIP表现为胰腺弥漫性肿大,2例为胰腺局限性肿大.11例病变区压脂T1WI信号明显减低,压脂T2 WI信号略增高,DWI病变区信号增高,动态增强后呈延迟强化;MRCP 8例显示胆总管胰头段呈鸟嘴样狭窄,6例胰管节段性狭窄,1例胰头部胰管局限性狭窄;5例胰腺病变区周围见包膜样结构,1例胰周间隙水肿;1例胰头周围淋巴结肿大及双肾多发结节.结论 AIP的MRI表现具有特征性.掌握AIP胰腺外病变的影像表现,有利于该病的诊断与鉴别诊断.     

自身免疫性胰腺炎的MSCT表现分析

目的探讨MSCT在自身免疫性胰腺炎诊断中的应用价值。方法回顾性分析13例经临床确诊的自身免疫性胰腺炎患者的CT资料。所有患者均行CT平扫及动态增强扫描,10例患者行二维或三维重建。结果 13例患者中,8例表现为胰腺弥漫性肿大,5例表现为局限性肿大;8例胰腺周围可见有增厚的"包膜样"结构;7例可见胆总管胰腺段管壁不规则增厚,管腔狭窄;3例可见胰管扩张;9例可见脾血管受累;8例可见腹膜后淋巴结肿大;4例可见胰周脂肪间隙受累。结论自身免疫性胰腺炎具有特征性的CT表现,MSCT在自身免疫性胰腺炎的诊治中具有重要的应用价值。     

自身免疫性胰腺炎MRI表现及随访分析

目的探讨自身免疫性胰腺炎(AIP)的MRI表现以及随访过程中影像动态变化。方法分析11例AIP病人的临床及MRI资料,观察AIP在类固醇治疗前、后不同时期的MRI表现。采用配对样本t检验,分别对初诊与自然病程下及初诊与类固醇治疗后的胰腺大小测量值进行比较。结果初诊时9例胰腺弥漫性肿大,1例胰头局限性肿大,1例胰体见局限性肿块;受累胰腺在T1WI低信号11例,T2WI高信号10例、等信号1例;4例显示胰周低信号带;胰腺病变区7例胰管不可见,2例间断显示,1例呈串珠状改变,1例胰体部胰管受压、移位;9例胰腺段胆管壁增厚。自然病程下随访,5例胰腺肿大程度及MRI信号异常与初诊病变相似,4例胆管壁病变范围较初诊病变加重。类固醇治疗后,6例胰腺肿大、MRI信号异常以及胆管壁增厚趋于正常,胰周低信号带消失。有效治疗后3例胰腺病变复发,复发性AIP的MRI表现与初诊病变相似,其中1例胰体尾前方出现假性囊肿。初诊与自然病程下胰腺大小差异无统计学意义(P0.05),初诊与类固醇治疗后胰腺大小差异有统计学意义(P0.05)。结论 AIP的MRI表现有一定特征,MRI可用于诊断AIP,评估类固醇疗效,长期随访以及了解有无病变复发。     

局限性自身免疫性胰腺炎的CT影像学特征分析

目的探讨局限性自身免疫性胰腺炎(focal autoimmune pancreatitis,f-AIP)的CT影像学表现特点,以期提高其影像学鉴别诊断水平。方法回顾性分析13例经组织学、IgG4检验或类固醇激素治疗证实的局限性自身免疫性胰腺炎患者的CT影像学资料,从胰腺形态表现、病变区密度及强化方式、胆胰管改变和假包膜结构显示等情况进行分析。结果本研究13例局限性自身免疫性胰腺炎患者中,13例均有局部胰腺肿大(胰头部3例,胰体尾部5例,胰尾部5例),与正常胰腺比较,CT平扫提示病变区密度降低(4例)或降低不明显(9例),增强扫描动脉期均见病变区强化程度较正常胰腺减低,门脉期及延迟期均提示病变区逐渐均匀强化,与正常胰腺强化程度相仿。7例显示病变区有假包膜结构,4例胆管扩张,胰管不规则硬化狭窄显示7例。结论局限性自身免疫性胰腺炎CT影像学表现具有一定的特征性,正确掌握这些特征有助于提高诊断准确率,从而避免不必要的手术治疗。     

自身免疫性胰腺炎的MRI诊断

目的:探讨自身免疫性胰腺炎(AIP)的MRI诊断价值。方法:搜集12例临床证实的AIP患者资料,12例均行MRI平扫、增强扫描及磁共振胰胆管水成像(MRCP),分析总结AIP的MRI表现特点。结果:12例AIP中7例表现为弥漫性胰腺体积增大,1例表现为胰腺体尾部肿大,MRI平扫胰腺信号欠均匀,T1WI呈高低混杂信号,T2WI信号普遍增高,另4例以胰头肿大为主,MRI示胰头区类似软组织信号肿块影,与周围胰腺组织信号一致;病灶增强扫描动脉期强化不明显,门脉期逐渐强化;MRCP示胆总管胰腺段变细,伴肝内外胆管不同程度扩张,胰腺管弥漫性狭窄。结论:AIP的MRI表现具有一定特异性,对AIP的临床诊断及治疗有一定指导意义。     

自身免疫性胰腺炎的MRI特征分析

目的 :探讨自身免疫性胰腺炎(autoimmune pancreatitis,AIP)的MRI特征。方法 :回顾性分析9例AIP患者的MRI资料,分析病变胰腺的形态、MRI信号改变及强化特点,胆总管、胰管改变,以及胰腺周围的MRI表现。结果:9例MRI图像均见胰腺体积增大,6例呈弥漫性肿大,3例局限性肿大;9例均见MRI信号改变,T2WI呈稍高信号,T1WI呈稍低信号,DWI呈高信号,动态增强扫描呈均匀延迟强化;7例胰腺周围可见包膜样结构;MRCP示6例胆总管胰腺段狭窄,呈"鸟嘴状",9例均见胰管节段性狭窄;2例胰腺周围见少量渗出,1例胰腺实质内及胰腺周围可见多发性大小不等的假性囊肿形成。结论:AIP的MRI表现具有特征性,结合临床有助于AIP的正确诊断。     

自身免疫性胰腺炎影像诊断进展

自身免疫性胰腺炎是由自身免疫异常引发的特殊类型的慢性胰腺炎,类固醇治疗效果显著,被认为是IgG4相关性全身性疾病的胰腺受累表现,其他受累器官包括胆管、胆囊、肾脏、腹膜后组织、涎腺等。主要的影像表现是弥漫性或局限性胰腺肿大以及胰管不规则狭窄,有时与胰腺癌等疾病鉴别困难。由于没有特异性诊断方法,自身免疫性胰腺炎通常需要综合性诊断,因此从影像诊断学上提高对该病的认识,对于该病的早期诊断和治疗相当重要。     

胰腺导管内乳头状黏液性肿瘤的MRI诊断

目的 探讨胰腺导管内乳头状黏液性肿瘤的MRI表现特点及诊断价值.资料与方法 回顾性分析经手术病理证实的10例胰腺导管内乳头状黏液性肿瘤的MRI表现.结果 (1)主胰管型3例,分别为导管内乳头状黏液腺癌、腺瘤癌变和腺瘤;MRI表现为主胰管弥漫性扩张,扩张的主胰管内见实性成分的肇结节.(2)6例分支胰管型,除l例为导管内乳头状黏液腺瘤伴不典型增生外,其余均为腺瘤;MRI表现为与主胰管相通的胰腺内囊性病灶,囊性病灶多呈"葡萄"样外观,其内可见索条形分隔及乳头状突起的壁结节.(3)混合型1例,MRI表现为主胰管及分支胰管内乳头状黏液腺瘤.结论 MRI在胰腺导管内乳头状黏液性肿瘤的诊断中具有重要作用.     

自身免疫性胰腺炎的MRI表现及临床分析

目的探讨自身免疫性胰腺炎（AIP）的MRI表现及临床特点。资料与方法搜集3例AIP患者的MRI资料,3例均行MRI平扫、增强扫描及磁共振胰胆管水成像（MRCP）。结果3例AIPMRI平扫均表现胰腺体积弥漫性增大,信号不均匀,胰周少量积液。增强扫描呈延迟强化。MRCP示胆总管胰腺段狭窄及其以上胆管扩张,胰管不规则狭窄。3例经激素治疗有效。结论MRI在AIP的诊断中作用显著,对临床诊断及治疗有重要指导意义。     

The MRI diagnosis of autoimmune pancreatitis

目的:探讨自身免疫性胰腺炎(ALP)的MRI诊断价值.方法:搜集12例临床证实的AIP患者资料,12例均行MRI平扫、增强扫描及磁共振胰胆管水成像(MRCP),分析总结AIP的MRI表现特点.结果:12例AIP中7例表现为弥漫性胰腺体积增大,1例表现为胰腺体尾部肿大,MRI平扫胰腺信号欠均匀,T1 WI呈高低混杂信号,T2 WI信号普遍增高,另4例以胰头肿大为主,MRI示胰头区类似软组织信号肿块影,与周围胰腺组织信号一致;病灶增强扫描动脉期强化不明显,门脉期逐渐强化;MRCP示胆总管胰腺段变细,伴肝内外胆管不同程度扩张,胰腺管弥漫性狭窄.结论:AIP的MRI表现具有一定特异性,对AIP的临床诊断及治疗有一定指导意义.     

Autoimmune pancreatitis: imaging findings on contrast-enhanced MR, MRCP and dynamic secretin-enhanced MRCP

Purpose

This study retrospectively determined magnetic resonance (MR), MR cholangiopancreatography (MRCP) and secretin-MRCP findings in patients with autoimmune pancreatitis (AIP).

Materials and methods

The MR examinations of 28 patients with histopathologically proven AIP were reviewed. In 14 cases, secretin-enhanced MRCP was performed. The observers evaluated pancreatic parenchymal enlargement, signal intensity abnormalities, enhancement, vascular involvement, bile-duct diameter and main pancreatic duct (MPD) narrowing (diffuse/focal/segmental). After secretin administration, the presence of the “duct-penetrating” sign was evaluated.

Results

MR imaging showed diffuse pancreatic enlargement in 8/28(29%) cases, focal pancreatic enlargement in 16/28 (57%) cases and no enlargement in 4/28 (14%) cases. The alteration of pancreatic signal intensity was diffuse in 8/28 (29%) cases (eight diffuse AIP) and focal in 20/28 (71%) cases (20 focal AIP). Delayed pancreatic enhancement was present in all AIP, with peripheral rim of enhancement in 8/28 (29%) AIP (1/8 diffuse, 7/20 focal); vascular encasement was present in 7/28 (25%) AIP (1/8 diffuse, 6/20 focal); distal common bile duct narrowing was present in 12/28(43%) AIP (5/8 diffuse, 7/20 focal). MRCP showed MPD narrowing in 17/28 (61%) AIP (4/8 diffuse, 15/20 focal), MPD dilation in 8/28(29%) AIP (3/8 diffuse, 5/20 focal) and normal MPD in1/8 diffuse AIP. Secretin-MRCP showed the duct-penetrating sign in 6/14(43%) AIP (one diffuse AIP with MPD segmental narrowing, five focal AIP with MPD focal narrowing), demonstrating integrity of the MPD.

Conclusions

Delayed enhancement and MPD stenosis are suggestive for AIP on MR and MRCP imaging. Secretin-enhanced MRCP is a problem-solving tool in the differential diagnosis between focal AIP and ductal adenocarcinoma.     

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.     

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...     

Diffuse pancreatic ductal adenocarcinoma: characteristic imaging features

PURPOSE: To evaluate imaging findings of diffuse pancreatic ductal adenocarcinoma. MATERIALS AND METHODS: We included 14 patients (4 men and 10 women; mean age, 64.5 years) with diffuse pancreatic ductal adenocarcinoma on the basis of retrospective radiological review. Two radiologists retrospectively reviewed 14 CT scans in consensus with respect to the following: tumor site, peripheral capsule-like structure, dilatation of intratumoral pancreatic duct, parenchymal atrophy, and ancillary findings. Eight magnetic resonance (MR) examinations with MR cholangiopancreatography (MRCP) and seven endoscopic retrograde cholangiopancreatography (ERCP) were also reviewed, focusing on peripheral capsule-like structure and dilatation of intratumoral pancreatic duct. RESULTS: CT revealed tumor localization to the body and tail in 11 (79%) patients and peripheral capsule-like structure in 13 (93%). The intratumoral pancreatic duct was not visible in 13 (93%). Pancreatic parenchymal atrophy was not present in all 14 patients. Tumor invasion of vessels was observed in all 14 patients and of neighbor organs in 8 (57%). On contrast-enhanced T1-weighted MR images, peripheral capsule-like structure showed higher signal intensity in five patients (71%). In all 11 patients with MRCP and/or ERCP, the intratumoral pancreatic duct was not dilated. CONCLUSION: Diffuse pancreatic ductal adenocarcinoma has characteristic imaging findings, including peripheral capsule-like structure, local invasiveness, and absence of both dilatation of intratumoral pancreatic duct and parenchymal atrophy.     

Clonorchiasis of the pancreas

Three patients with pancreatic clonorchiasis were examined with endoscopic retrograde pancreatography. On each of the three cases there was diffuse irregular dilatation of tributaries of the pancreatic duct in the pancreatic tail. The main pancreatic duct and tributaries draining into the body and head portion were not dilated. A sonogram from one patient showed diffuse enlargement of the pancreas, especially the tail. All three patients showed typical cholangiographic findings of hepatic clonorchiasis, namely diffuse peripheral intrahepatic bile duct dilatation with no or minimal dilatation of the extrahepatic duct. When the tributaries of the pancreatic duct in the tail of the pancreas are diffusely dilated, in the appropriate clinical setting, pancreatitis caused by Clonorchis sinensis should be considered.     

Mass-forming autoimmune pancreatitis and pancreatic carcinoma: differential diagnosis on the basis of computed tomography and magnetic resonance cholangiopancreatography, and diffusion-weighted imaging findings

Purpose:

To differentiate mass‐forming autoimmune pancreatitis (AIP) from pancreatic carcinoma by means of analysis of both computed tomography (CT) and magnetic resonance imaging (MRI) findings.

Materials and Methods:

Ten patients with mass‐forming AIP diagnosed by revised clinical criteria of Japan Pancreas Society and 70 patients with pathologically proven pancreatic carcinoma were enrolled in this retrospective study. Two radiologists independently evaluated the CT and MR imaging findings. The sensitivity, specificity, and odds ratio of significant imaging findings and combinations of findings were calculated.

Results:

Seven findings were more frequently observed in AIP patients: (i) early homogeneous good enhancement, (ii) delayed homogeneous good enhancement, (iii) hypoattenuating capsule‐like rim, (iv) absence of distal pancreatic atrophy, (v5) duct penetrating sign, (vi) main pancreatic duct (MPD) upstream dilatation ≤ 4 mm, and (vii) an apparent diffusion coefficient (ADC) ≤ 0.88 × 10^?3 mm²/s. When the findings of delayed homogeneous enhancement and ADC ≤ 0.88 × 10^?3 mm²/s were both used in diagnosis of mass‐forming AIP, a sensitivity of 100% and a specificity of 100% were achieved. When 4 of any of the 7 findings were used in the diagnosis of AIP, a sensitivity of 100% and a specificity of 98% were achieved.

Conclusion:

Analysis of a combination of CT and MR imaging findings allows for highly accurate differentiation between mass‐forming AIP and pancreatic carcinoma. J. Magn. Reson. Imaging 2012;35:827–836. © 2011 Wiley Periodicals, Inc.