自身免疫性胰腺炎的MR诊断与鉴别诊断

目的分析自身免疫性胰腺炎的MRI表现,旨在提高对其诊断的准确率。方法对经临床证实的10例自身免疫性胰腺炎进行回顾性分析,10例均行MR平扫及增强扫描检查。结果胰腺弥漫性受累(8/10),胰头局限性肿块(1/10),胰体尾部受累(1/10);6例可见"假包膜"征。MRCP:9例胆总管胰腺段狭窄,8例见胰管局限性或弥漫性狭窄,1例主胰管未见显示;动态增强后病变区呈延迟性强化。结论 MRI表现有一定的特点,需要和其它胰腺病变进行鉴别诊断,从而做出正确的诊断。     

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.     

胰腺实性假乳头状瘤影像学表现与病理对照分析(附10例报告)

目的 通过胰腺实性假乳头状瘤(SPTP)的影像学表现特征与病理对照分析,提高对本病的认识和诊断.方法 回顾性分析经手术病理证实的10例SPTP的资料,将影像学(CT及MRI)表现与病理对照.10例SPTP中,女9例,男1例.结果 10例病变均为单发,位于胰头5例,胰颈部1例,胰体尾部2例,胰尾部1例,异位1例.影像学表现为圆形、类圆形囊实性肿块;平扫主要表现为囊实性混杂密度/信号,3例钙化灶;10例肿瘤均有包膜.增强扫描后,2例动脉期见肿瘤血管影,各肿瘤实性成分及包膜均呈渐进性强化.2例胰管轻度扩张.1例胆管及胰管扩张.结论 SPTP好发于年轻女性,临床症状不典型,影像学表现为具有包膜的囊实性肿块,可伴出血、钙化,实性部分及包膜渐进性强化.     

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。     

胰腺实性-假乳头状瘤的多层螺旋CT诊断

目的:探讨胰腺实性-假乳头状瘤(SPTP)在多层螺旋CT上的影像特点.方法:回顾性分析40例经手术切除和病理学证实的胰腺实性-假乳头状瘤的临床、多层螺旋CT影像学资料,结合CTA、多平面重建和二维曲面重建等影像技术观察其影像学表现,分析影像学表现与病理结果的相关性.结果:女性35例,男性5例.40例患者SPTP影像学表现中,22例位于胰头,5例位于胰颈体交界区,6例位于胰体,3例位于胰体尾部,3例位于胰尾部,1例胰头、胰体尾部均见;类圆形30例,圆形5例,分叶状4例,表现为胰头增大1例,边界清楚,包膜完整;肿块多数较大,最大横断面达15 cm×18 cm,最小1.0 cm×1.1 cm;肿块完全实性7例,囊实性成分33例,其中囊性为主8例,实性为主17例,囊实性相仿8例.实性部分CT平扫呈稍低或等密度,增强扫描动脉期实性部分可见中等强化,至门静脉期肿瘤实性部分渐进性强化略高于动脉期,但强化程度均略低于正常胰腺组织,囊性部分平扫及增强均呈低密度.CT表现1例患者见恶性倾向,9例推压、包绕肠系膜血管,8例脾血管受压,3例累及肝总动脉及分支,2例累及十二指肠,11例伴有胰管扩张,其中1例伴有明显胆总管及肝内胆管扩张,13例伴有钙化.病理示良性37例,潜在恶性或低度恶性3例.结论:胰腺实性-假乳头状瘤具有特征性的影像学表现,螺旋CT能协助诊断,运用CTA、多平面重建和二维曲面重建等影像技术有助于术前评估肿瘤的良恶性.     

胰腺实性-假乳头状瘤的CT影像分析

目的:分析胰腺实性-假乳头状瘤的CT表现,探讨CT对胰腺实性-假乳头状瘤的诊断价值.方法:回顾性分析手术病理证实的5例胰腺实性-假乳头状瘤的CT特征,包括肿瘤的部位、大小、形态、密度及强化特征.结果:5例肿瘤位于胰头1例,胰体尾部4例.5例瘤体均为囊、实混合性,其中3例肿瘤有钙化,增强后实性部分均有强化,囊性部分无强化.肿瘤均有完整包膜,不伴有胆总管和胰管扩张.结论:胰腺实性-假乳头状瘤的CT表现有一定特征,对确定手术方案有重要价值.     

胰腺实性假乳头状瘤的CT表现(附12例报告并文献复习)

目的探讨胰腺实性假乳头状瘤(SPTP)的CT影像特征。方法回顾性分析12例经手术病理证实的SPTP患者的临床及CT资料,并复习文献。结果 11例患者为女性,1例为男性,年龄13~52(34.6±2.0)岁。均为单发病灶,其中胰头部4例,胰颈2例,胰体尾部6例。肿瘤体积较大,平均直径约(6.5±1.6)cm,形态规则,边界清晰。CT影像呈外生性生长的囊实性肿块,密度不均匀,6例见钙化,2例见出血。增强动脉期,门静脉期及延迟期实性成分强化逐步增强,呈渐进性强化方式,强化程度低于正常胰腺实质,囊性成分无强化,并见较明显均匀强化的纤维包膜。12例均未见胰管及胆管扩张。结论胰腺囊实性病灶,伴钙化、出血,增强呈渐进性强化,包膜明显强化的CT表现特征,结合临床资料,可提高SPTP的正确诊断。     

胰腺少见囊性病变的CT及MRI诊断

目的 探讨胰腺少见囊性肿瘤的影像学特征,提高诊断水平. 方法 回顾分析经手术病理证实的11例少见胰腺囊性肿瘤的临床特征及术前平扫和增强的CT、MRI表现,其中表皮样囊肿4例, 淋巴上皮囊肿4例,淋巴管瘤3例. 结果 (1)表皮样囊肿病变位于胰尾部,囊壁光滑完整,CT平扫囊性病变内的实质成分和脾的密度相同.CT和MRI增强后实质成分表现出和脾完全相同的强化方式.(2)淋巴上皮囊肿老年男性多见,病变呈现多房状境界清楚的肿块.CT平扫呈等密度,MRI T_1WI和T_2WI上混杂的等高信号,增强后囊壁分隔强化.(3)淋巴瘤表现为体尾部的分叶状多囊性病变,CT平扫密度略低于胰腺实质,MRI平扫呈长T_1长T_2信号.增强后分隔和囊壁轻度强化,肿瘤不与胰管交通,胰管轻度受压移位.结论胰腺少见的囊性病变具有一定的特征性的临床和影像学特征.     

螺旋CT平扫对急性胰腺炎的诊断价值

目的探讨急性胰腺炎的CT平扫特征及其诊断价值。方法对经临床明确诊断的30例急性胰腺炎CT表现进行分析评价。结果30例中CT诊断为急性单纯性水肿性胰腺炎13例,表现为胰腺弥漫性或局限性增大,密度轻度减低,轮廓模糊,以及胰周积液。急性出血坏死性胰腺炎17例,表现为胰腺明显增大,密度弥漫性减低,坏死区密度更低,出血区密度高于正常组织,明显的胰周脂肪坏死和积液。结论螺旋CT平扫是急性胰腺炎简便有效的影像检查方法。     

胰腺实性假乳头状瘤影像学诊断与病理对照分析

目的:分析胰腺实性假乳头状瘤(SPTP)影像学表现,并与病理学对照,旨在提高对该病的认识及诊断水平。方法:回顾性分析13例经手术及病理证实的胰腺实性假乳头状瘤的临床、CT和MRI资料,将影像学表现与手术病理结果对照。结果:SPTP好发于20~40岁女性,胰尾、胰头为好发部位。影像学多表现为境界清晰的圆形、类圆形胰腺肿块,瘤体通常较大(≥5cm)。平扫主要表现为囊实性混杂密度/信号,实性结构边缘分布为主,部分呈乳头状或壁结节样突起。动态增强后实性部分早期轻度强化,后期呈渐进性强化。13例肿瘤均有包膜,多伴有出血及囊变,出血在MRI上多呈现为特征性的“分层现象”。所有病灶无论其大小及在胰腺所处位置,均未见胆管、胰管扩张,罕见腹腔淋巴结肿大及远处脏器转移。结论:胰腺实性假乳头状瘤影像学表现具有相对特征性,CT和MRI对其诊断有重要价值,其中MRI在显示病灶出血、囊变、包膜方面更具优势。     

Autoimmune pancreatitis: imaging features

PURPOSE: To retrospectively determine imaging findings in patients with autoimmune pancreatitis. MATERIALS AND METHODS: Twenty-nine patients (25 male and four female; mean age, 56 years; range, 15-82 years) with histopathologic diagnosis of autoimmune pancreatitis were examined. Data were reviewed by two radiologists in consensus. Imaging findings for review included those from helical computed tomography (CT), 25 patients; magnetic resonance (MR) imaging with MR cholangiopancreatography (MRCP), four patients; endoscopic ultrasonography (US), 21 patients; endoscopic retrograde cholangiopancreatography (ERCP), 19 patients; and percutaneous transhepatic cholangiography, one patient. Images were analyzed for appearances of pancreas, biliary and pancreatic ducts, and other findings, such as peripancreatic inflammation, encasement of vessels, mass effect, pancreatic calcification, peripancreatic nodes, and peripancreatic fluid collection. Follow-up images were available in nine patients. Serologic markers such as serum immunoglobulin G (IgG) and antinuclear antibody levels were available in 12 patients. RESULTS: CT showed diffuse (n = 14) and focal (n = 7) enlargement of pancreas. Seven patients had minimal peripancreatic stranding, with lack of vascular encasement, calcification, or peripancreatic fluid collection. Nine patients had enlarged peripancreatic lymph nodes. MR imaging showed focal (n = 2) and diffuse (n = 2) enlargement with rimlike enhancement in one. MRCP revealed pancreatic duct strictures in two and sclerosing cholangitis-like appearance in one. Endoscopic US showed diffuse enlargement of pancreas with altered echotexture in 13 patients and focal mass in the head in six. ERCP showed stricture of distal common bile duct in 12 patients, irregular narrowing of intrahepatic ducts in six, diffuse irregular narrowing of pancreatic duct in nine, and focal stricture of proximal pancreatic duct in six. Serologic markers showed increased IgG and antinuclear antibody levels in seven of 12 patients. At follow-up, CT abnormalities and common bile duct strictures resolved after steroid therapy in three patients. CONCLUSION: Features that suggest autoimmune pancreatitis include focal or diffuse pancreatic enlargement, with minimal peripancreatic inflammation and absence of vascular encasement or calcification at CT and endoscopic US, and diffuse irregular narrowing of main pancreatic duct, with associated multiple biliary strictures at ERCP.     

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.     

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.     

The CT findings of pancreatic acinar cell carcinoma in five cases

ObjectivesThe aim of this study is to analyze the computed tomographic (CT) findings of pancreatic acinar cell carcinoma (ACC).Materials and methodsThe CT features and clinical presentations of five patients (four men, one woman; mean age, 52 years) with pathology-proven pancreatic ACC were reviewed. The image characteristics included the lesion location and size, the exophytic nature of the tumor, intratumoral hemorrhage, calcification, the presence of cystic or necrotic components, bile or pancreatic duct dilation, attenuation on the noncontrast image, attenuation on the arterial- and venous-phase images, peripancreatic invasion, peripancreatic lymphadenopathy, and distant metastases.ResultsThe tumors were located at the pancreatic tail in three cases and at the pancreatic head in two cases. The average lesion size was 5.3 cm. Exophytic features and cystic/necrotic components were found in 80% (4/5) and 60% (3/5) of cases, respectively. The ACC showed a mild hypodense appearance on noncontrast CT in 100% (3/3) of cases and a hypodense appearance on arterial-/venous-phase CT in 80% (4/5) of cases. The exception was one lesion that showed a significantly hyperdense appearance and a mildly hyperdense appearance on the arterial- and venous-phase images. None of the CT images showed enhancement of a capsule, calcification, intratumoral hemorrhage, bile or pancreatic duct dilation, vascular encasement, or distant metastatic disease, but three cases showed peripancreatic invasion and lymphadenopathy.ConclusionsWith persistent mild enhancement, the typical ACC appears as an exophytic tumor with a focal cystic/necrotic component and the lack of ductal dilatation. The predilection for older male patients and elevated serum alpha fetoprotein are useful clinical features for confirming an ACC diagnosis.     

Intraductal papillary mucinous neoplasms of the pancreas: Correlation of helical CT features with pathologic findings

Objective

To evaluate the CT features of intraductal papillary mucinous neoplasms of the pancreas (IPMNs), and to compare with pathological findings in order to identify CT features that can be helpful in differentiating benign IPMNs from malignant IPMNs.

Materials and methods

The CT findings in 25 patients were reviewed for tumor location, tumor type, dilatation of the main pancreatic duct (MPD), MPD involvement, mural node or solid attenuating component, tumor size in branch duct or mixed duct type, dilatation of common bile duct (CBD) and invasion of surrounding structures. The data was subjected to Chi-Square Tests or Fisher's Exact Test using SPSS13.0 software with p value < 0.05 indicating significant statistical difference.

Results

Presence of mural node or solid enhancing component, size of mural node or solid enhancing component ≥7 mm, dilatation of CBD was more common in malignant IPMNs (p < 0.05). None of tumor location, tumor type, dilatation of MPD, MPD involvement, tumor size, and invasion of surrounding structures was statistically significant in differentiating benign from malignant IPMNs.

Conclusions

CT features suggestive of malignant or invasive IPMNs include presence of mural node or solid enhancing component, size of mural node or solid enhancing component ≥7 mm, and dilatation of CBD.     

Ⅰ型自身免疫性胰腺炎的CT及MRI表现

目的 探讨I型自身免疫性胰腺炎(I-AIP)的CT及MRI表现.资料与方法 回顾性分析16例经病理证实的I-AIP的临床资料、CT及MRI表现.结果 16例I-AIP中,14例IgG4水平升高;胰腺弥漫型受累9例,呈"腊肠状"改变,其中6例可见"胶囊征";局灶型受累7例.CT平扫呈均匀等或低密度,MRI平扫T1WI呈低...     

Intraductal papillary tumors of the pancreas. Histopathologic correlation of MR cholangiopancreatography findings

Purpose: To evaluate MR cholangiopancreatography (MRCP) findings of intraductal papillary tumors of the pancreas and correlate them with histopathology.Material and Methods: Seventeen patients with intraductal papillary tumor of the pancreas underwent MRCP before surgery. MRCP findings were correlated to histopathology with regard to the presence of septa and excrescent nodules in the cystic lesion, communication between the cystic lesion and the main pancreatic duct (MPD), degree of dilatation of MPD, and dilatation of the common bile duct (CBD).Results: MRCP demonstrated septa in 17 cases (100%), excrescent nodules in 8 cases (47.1%), communication between the intraductal papillary tumor and the MPD in 14 cases (82.3%), dilatation of MPD over 50% in 6 cases (35.3%), and dilatation of CBD in 3 cases (17.6%). These findings showed excellent correlation with histopathology. The septum on MRCP corresponded with a layer of connective tissue with pancreatic duct epithelium. Excrescent nodules in the carcinomas consisted not only of malignant cells, but also of dysplasia and adenoma. Excrescent nodules in adenomas were consistent not only with minimal papillary growth of adenoma, but also with proliferation of fibrosis, and hematoma and organized fibrin with minimal fibrosis. Pancreatic tissue was affected by chronic pancreatitis in all cases. Cases with dilatation of CBD on MRCP were due to microscopic invasion by the carcinoma.Conclusion: MRCP appearances of intraductal papillary tumors are well correlated with the findings at histopathology.     

胰腺原发性类癌的CT表现

目的探讨胰腺原发性类癌的CT表现。方法回顾性分析经病理证实的5例胰腺类癌的CT表现。结果本组病例肿块最大径2．0—11．0cm，平均6．4cm。CT平扫肿瘤实质较胰腺稍低，密度均匀者2例，不均匀者3例，肿块钙化者1例。动脉期肿块不均匀明显强化者3例，轻度强化者2例，肿瘤实质密度均低于胰腺，有不同程度的坏死，其中1例中央坏死明显，无强化，整个肿块呈囊状；静脉期肿块强化程度明显，与胰腺相似或稍低；1例延迟期肿块强化程度高于胰腺。肝转移1例，同时伴腹膜后淋巴结肿大及血管侵犯。未见胆管及胰管扩张。结论胰腺类癌CT表现主要有较少引起胆道及胰管扩张，对周围血管较少累及，钙化较常见；增强后肿瘤实质明显强化，静脉期强化程度与胰腺相似，延迟期强化程度高于胰腺。     

Intraductal papillary mucinous neoplasm of pancreas: multi-detector row CT with 2D curved reformations--correlation with MRCP

PURPOSE: To retrospectively compare accuracy of multi-detector row computed tomography (CT), combined with two-dimensional (2D) curved reformations, and that of magnetic resonance (MR) cholangiopancreatography (MRCP) for characterization of intraductal papillary mucinous neoplasm (IPMN) as malignant, with pathologic examination as reference standard. MATERIALS AND METHODS: Institutional review board approval was obtained, informed consent was waived, and study was HIPAA compliant. Twenty-five patients (12 women, 13 men; age range, 44-88 years) with pathologically proved IPMN were examined with dual-phase CT with 1.25-mm-thick sections for pancreatic phase; 2D curved reformations along main pancreatic duct (MPD) were generated. T2-weighted MRCP included thick- and thin-slab single-shot fast spin-echo imaging and transverse fast spin-echo imaging. Two radiologists, blinded to surgical and pathologic findings, evaluated images for lesion location, septa, mural nodules, communication with MPD, extent and diameter of MPD dilatation, calcifications, and vascular encasement. Malignancy was suspected when one of the following was present: MPD diameter larger than 10 mm, mural nodules, vascular encasement, peripancreatic lymphadenopathy, or metastases. Sensitivity and specificity values for prediction of malignancy were calculated for CT and MRCP. Interobserver variability was determined (kappa analysis). RESULTS: Excellent correlation between modalities was observed. Cyst communication was seen in 20 and 21 of 24 branch pancreatic duct (BPD) IPMNs with CT and MRCP, respectively. Sensitivity, specificity, and accuracy for detection of malignancy were 70%, 87%, and 76% (CT) and 70%, 92%, and 80% (MRCP), respectively. Interobserver agreement was good to perfect for both readers in all comparisons (overall, kappa = 0.70-1.00). CONCLUSION: CT combined with 2D curved reformation can provide imaging details of IPMN, including communication of BPD IPMN with MPD, that are almost equivalent to those provided at MRCP. Presence of mural nodules, dilated MPD (>10-mm diameter), or thick septa at CT or MRCP may be used as independent predictors of malignancy.     

Chronic pancreatitis: reassessment with current CT

A retrospective analysis was performed of contrast material-enhanced current-generation computed tomographic (CT) examinations in 56 patients with documented chronic pancreatitis. Dilatation of the main pancreatic duct was seen in 68% of cases, parenchymal atrophy in 54%, pancreatic calcifications in 50%, fluid collections in 30%, focal pancreatic enlargement in 30%, biliary ductal dilatation in 29%, and alterations in peripancreatic fat or fascia in 16%. The relatively small proportion of examinations in which no abnormalities were observed, 7%, differs from that in early reports, as does the absence of generalized pancreatic enlargement. Pancreatic ductal dilatation and parenchymal atrophy were notably more prevalent than reported previously. Nine of the 17 patients with focal pancreatic enlargement had calculi within the mass, which suggested benign disease; of the eight other patients, two of whom had coexistent carcinoma, this finding was absent and the masses were considered indeterminate at CT.