胰腺导管内乳头状黏液瘤影像特征及误诊病例分析

目的 分析胰腺导管内乳头状黏液瘤(IPMN)影像学表现和误诊原因,减少误诊率.方法 回顾性分析术前影像诊断或怀疑为IPMN和术前影像误诊为胰腺其他疾病但是术后被确诊为IPMN患者的资料,共计130例.由2名高年资影像诊断医生统计资料,总结IPMN影像学表现,分析误诊原因,找出对策.结果 130例患者经病理确诊为IPMN有105例(80.7%),确诊为胰腺其他病变25例(19.2%);IPMN与慢性胰腺炎(CP)和浆液性囊腺瘤(SCN)间相互误诊病例最多.将IPMN按照病理级别分为轻至中度组和重度、浸润癌组,2组在囊肿直径、有无壁结节、有无分隔、主胰管直径、是否伴有肝内外胆管扩张组间有统计学差异(P<0.05).误诊的主要原因为影像科医生诊断时未完整结合患者的临床资料;对少见类型影像学表现认识不足;对于病变与胰管关系判断错误.结论 在诊断IPMN时需要结合病变临床特征,明确肿块与胰管之间的关系,全面掌握影像学表现;对于反复发作胰腺炎患者需考虑IPMN存在的可能;长期IPMN可以存在CP.     

磁共振成像技术对胰腺导管内乳头状黏液瘤的诊断价值

目的探讨胰腺导管内乳头状黏液瘤的MRI影像学特点,以提高该病的诊断准确率。方法搜集12例经手术证实的胰腺导管内乳头状黏液瘤患者的临床及影像学资料,回顾性分析主胰管型和分支胰管型的MRI表现。结果研究证实,12例中有主胰管型3例和分支胰管型9例。主胰管型MRI表现为主胰管节段性或弥漫性扩张,可伴有胰腺实质的萎缩;分支胰管型MRI表现为单房或多房型囊性病变,并与主胰管相通。结论 MRI对胰腺导管内乳头状黏液瘤是一种无创、有效的诊断方法,有助于提高该病的诊断准确率。     

胰腺导管内乳头状粘液性肿瘤的影像特征及其良恶性鉴别

目的 分析良、恶性胰腺导管内乳头状粘液性肿瘤(IPMN)的CT和MRI特征,探讨其对于IPMN良恶性的鉴别诊断价值.方法 选取经手术病理证实的70例IPMN患者的临床及影像资料.根据病理诊断将70例IPMN分为良性组和恶性组;筛选分析与鉴别IPMN良恶性相关的临床与影像特征,并绘制受试者工作特征曲线(ROC),评估其对...     

阑尾黏液性肿瘤影像学表现及病理相关性研究

目的：探讨阑尾黏液性肿瘤的影像学表现及其病理相关性,提高对该病的认识和诊断准确性。方法回顾性分析16例经手术病理证实的阑尾黏液性肿瘤影像资料,其中包括2例黏液性囊腺瘤,10例低级别黏液性肿瘤(LAMN)和4例黏液性囊腺癌,分析病变影像学表现及病理相关性。结果黏液性囊腺瘤多表现为长椭圆形或条形液性低密度,边界清晰,壁完整,密度均匀。黏液性囊腺癌多表现为不规则形囊实性肿块,边界不清,结节状及分隔强化,常侵犯邻近肠管;部分黏液性囊腺癌易伴发腹膜假性黏液瘤(PMP)及腹腔种植转移。LAMN介于黏液性囊腺瘤与黏液性囊腺癌之间,多数病例表现与黏液性囊腺瘤相似,部分病例与黏液性囊腺癌表现相似。结论阑尾黏液性肿瘤影像学表现多样,部分病例影像学表现具有一定特征性,CT 及 MRI 检查对该病的诊断具有较大价值。     

CT imaging spectrum of pancreatic serous tumors: Based on new pathologic classification

Purpose

The aim of this study is to retrospectively analyze the variety of CT findings based on new pathologic classification.

Materials and methods

During a 10-year period, 59 histopathologically proven pancreatic SCTs and 13 SCTs confirmed with typical image findings and strict clinical criteria were enlisted. Two radiologists analyzed CT images for the following items in consensus: location, size, outer margin, tumor shape, the presence of mural nodule, communication with main pancreatic duct (MPD), the presence and extent of MPD dilatation, calcification, central scar, and attenuation on pre- and post-contrast CT images. In addition, typicality of CT findings was determined. A typical finding was defined as a honeycomb appearance without or with oligocystic portion. In the cases with atypical features, the type of atypical features and differential diagnosis were recorded. For the shape of the tumor, tumors were categorized into the following groups: honeycomb without or with oligocystic, pleomorphic, purely oligolocular, unilocular cystic, hypovascular solid, hypervascular solid without or with oligocystic portion, and fingerlike cystic patterns.

Results

28 SCTs (38.9%) presented a honeycomb appearance with (n = 14) or without oligocystic portion (n = 14) and were classified as typical cases. The remaining 44 atypical cases (61.1%) presented the following: purely oligolocular pattern in 18; hypervascular solid without (n = 7) or with oligocystic portion (n = 2) in 9; pleomorphic in 8; unilocular cystic in 7; and fingerlike cystic pattern in 2. Most of the lesions manifesting as hypervascular solid lesions were confused with true solid hypervascular tumors such as neuroendocrine tumors or solid pseudopapillary tumors. For most of the remaining atypical lesions, mucinous cystic neoplasm or branch duct type IPMN were included as a differential diagnosis.

Conclusion

Serous cystic tumors of the pancreas can have variable CT appearances ranging from compactly solid hypervascular to clearly unilocular cystic, which reflect a varied macroscopic morphology. Only 38.9% of the SCTs show traditional typical CT features whereas a considerable proportion (61.1%) of SCTs showed atypical appearances, providing diagnostic challenges to radiologists.     

Intraductal papillary mucinous neoplasm penetrating to the stomach,duodenum, and jejunum demonstrated on MR cholangiopancreatography with an oral negative contrast agent

A 65‐year‐old man was referred to our hospital due to epigastric pain. Abdominal enhanced computed tomography (CT) demonstrated marked dilatation of the main pancreatic duct (MPD) and communication to the gastric and duodenal lumen was suspected. Esophagogastroduodenoscopy (EGD) showed a villous tumor with white mucous discharge in the posterior wall of the gastric corpus and duodenal bulb. Pathological specimens showed mucin‐producing epithelium with nuclear atypia that had developed in a papillary form. Based on these findings, we diagnosed intraductal papillary mucinous neoplasm (IPMN) arising in the MPD with penetration into the gastric and duodenal lumen. Magnetic resonance cholangiopancreatography (MRCP) with an oral negative contrast agent (manganese chloride tetrahydrate) showed a fistulous tract not only to the stomach and duodenum, but also to the jejunum. MRCP demonstrated mucous streaming with remarkably high intensity. In this case, an oral negative contrast agent was useful to distinguish mucous discharge from gastric fluid, facilitating the diagnosis of penetration to the jejunum. This finding was unobtainable by CT or EGD. When IPMN penetrating to other organs is suspected, MRCP with an oral negative contrast agent may provide important information. J. Magn. Reson. Imaging 2013;38:206–209. © 2013 Wiley Periodicals, Inc.     

Imaging pitfalls of pancreatic serous cystic neoplasm and its potential mimickers

The aim of this article is to clarify diagnostic pitfalls of pancreatic serous cystic neoplasm (SCN) that may result in erroneous characterization. Usual and unusual imaging findings of SCN as well as potential SCN mimickers are presented. The diagnostic key of SCN is to look for a cluster of microcysts (honeycomb pattern), which may not be always found in the center. Fibrosis in SCN may be mistaken for a mural nodule of intraductal papillary mucinous neoplasm (IPMN). The absence of cyst wall enhancement may be helpful to distinguish SCN from mucinous cystic neoplasm. However, oligocystic SCN and branch duct type IPMN may morphologically overlap. In addition, solid serous adenoma, an extremely rare variant of SCN, is difficult to distinguish from neuroendocrine tumor.     

Magnetic resonance pancreatography: comparison of two- and three-dimensional sequences for assessment of intraductal papillary mucinous neoplasm of the pancreas

The purpose was to compare two-dimensional (2D) magnetic resonance pancreatography (MRP) with 3D MRP to evaluate intraductal papillary mucinous neoplasm (IPMN). Thirty-four patients (22 men, 12 women; age range, 45–80 years) with IPMN (n = 40) were examined with MRP on 2D and 3D sequences. Two readers independently reviewed the images to assess the overall image quality, artifacts, lesion location, communication with main pancreatic duct, and potential for malignancy. The readers assigned their confidence level (1–5) for predicting ductal communication of the lesion. The results of MRP were compared with endoscopic retrograde pancreatography and surgical and histopathologic findings. Studies obtained with 3D MRP were of significantly higher technical quality than those obtained with 2D MRP. Although 3D MRP showed higher area under the ROC curve (Az) values for predicting ductal communication of the lesion, there was no statistical significance between Az values of 2D and 3D MRP (Az for 2D = 0.821, 0.864 for readers 1 and 2, respectively, and Az for 3D= 0.964, 0.921). Accuracies for discriminating benign from malignant lesions were 70 and 67.5% (reader 1 and 2, respectively, for 2D) and 62.5 and 80.1% (3D). 3D MRP showed superior image quality to that of 2D MRP but did not increase the diagnostic accuracy for predicting ductal communication of the lesion.     

2型糖尿病患者中胰腺导管内乳头状黏液性肿瘤影像学分析

目的分析2型糖尿病患者中胰腺导管内乳头状黏液性肿瘤(IPMN)的影像学良恶性表现,提高影像学诊断水平。方法选取我院经手术病理证实的2型糖尿病患者伴胰腺IPMN患者20例。记录肿瘤分型、部位、大小、囊壁结节、胰管扩张等影像学表现。结果 20例IPMN中,头颈部9例,体尾部11例;混合型8例,多表现为主胰管不同程度扩张并周围分支胰管扩张,分支型6例,表现为单发单囊或多房囊性病灶;肿瘤平均直径约25.2 mm,主胰管型6例,表现为全程主胰管不同程度扩张,平均直径约15.9 mm;良性17例,恶性3例(2例为主胰管型均伴壁结节,1例混合型)。结论糖尿病患者的胰腺IPMN具有较为特征的影像学良性及恶性表现,临床上应严格把握手术和随访指征,结合患者的其他临床资料评估决定。     

节细胞神经瘤的影像学表现

目的 探讨节细胞神经瘤的CT和MR表现.方法 回顾性分析18例经手术病理证实的节细胞神经瘤的CT、MR影像学资料,所有患者均接受CT平扫及增强扫描,2例接受MR平扫.结果 节细胞神经瘤好发于中青年,位于后纵隔8例,肾上腺5例,腹膜后4例,颈部1例.均为单发病灶、边界清楚,嵌入式生长可呈多种形态.CT平扫:12例为均匀低密度,平均CT值22～37 HU;6例密度不均,平均CT值13～46 HU,其中2例伴有坏死、囊变.2例见斑点状钙化.增强扫描:肿瘤各期均无强化4例,仅动脉期轻度强化5例,仅静脉期轻度强化2例,静脉期及延迟期呈轻、中度渐进性强化1例,三期呈渐进性强化6例;坏死及囊变部分未见强化.2例肿瘤内见肋间后动脉穿行,1例见腰动脉穿行并见细小分支滋养肿瘤.2例下腔静脉推挤受压移位,1例见颈部大血管被包绕.MR平扫:1例信号均匀,1例信号不均;T1WI表现为低信号,T2 WI呈高信号为主,脂肪抑制(SPIR)及扩散加权成像(DWI)呈高信号.结论 节细胞神经瘤的CT及MR表现具有一定特征性,尤其是CT示肿瘤为均匀低密度、伴有斑点状钙化、肿瘤内血管穿行但未受侵,增强扫描动脉期无明显强化或轻度强化,呈渐进性强化方式,DWI示肿瘤呈高信号时,应考虑节细胞神经瘤的可能.     

Intraductal papillary mucinous neoplasm of the pancreas: differentiate from chronic pancreatits by MR imaging

Purpose

To evaluate the differentiating factors for intraductal papillary mucinous neoplasm of the pancreas and chronic pancreatitis as determined by MR imaging.

Materials and methods

During a three-year period, we performed MR imaging on 33, consecutive patients with IPMN and on 41 patients with chronic pancreatitis. All IPMNs were confirmed by surgery. Two radiologists retrospectively analyzed the ductal change, the cyst shape, CBD dilatation, lymphadenopathy, and parenchymal change. The sensitivity and specificity were calculated for each MRI findings using the Chi square test. Statistically significant MR findings were further analyzed using multivariate logistic regression analysis. The diagnostic performance was evaluated according to the area under the receiver operating characteristic curve (A_z) using specific MRI findings. Simple κ statistics were used to evaluate the inter-observer reliability.

Results

Statistically specific findings for IPMN compared with those for chronic pancreatitis, were duct dilatation without stricture (specificity = 95.1%, sensitivity = 75.8%, p < 0.0001), bulging ampulla (specificity = 97.6%, sensitivity = 30.3%, p < 0.0001), nodule in a duct (specificity = 100%, sensitivity = 15.2%, p < 0.0004), grape-like cyst shape (specificity = 97.6%, sensitivity = 78.8%, p < 0.0001), and nodule in a cyst (specificity = 100%, sensitivity = 24.2%, p < 0.0001). Statistically specific findings for chronic pancreatitis compared with those for IPMN, were duct dilatation with strictures (specificity = 93.9%, sensitivity = 95.1%, p < 0.0001), the presence of a stone (specificity = 97.0%, sensitivity = 56.1%, p < 0.0001), and a unilocular cyst shape (specificity = 93.9%, sensitivity = 34.1%, p < 0.0004). Duct dilatation without stricture and a grape-like cyst shape were independently associated with the IPMN. Duct dilatation with strictures was independently associated with the chronic pancreatitis. Interobserver agreement was good to excellent for each finding (κ = 0.762–1.000).

Conclusion

Highly specific findings for IPMN include duct dilatation without stricture, bulging ampulla, nodule in a duct, grape-like cyst shape, and nodule in a cyst. MRI is very useful for differentiating IPMN from chronic pancreatitis using these specific findings.     

卵巢良性囊性病变的CT、MRI表现

目的 分析卵巢良性囊性病变(BOCL)的CT和MRI表现,提高对其的影像诊断与鉴别诊断水平.方法 回顾分析48例经手术病理证实的BOCL的CT和MRI表现.35例行CT平扫,其中20例行CT增强检查;8例行MRI平扫,其中3例行MRI增强检查及扩散加权成像(DWI)检查;5例同时行CT、MRI检查.结果 囊肿11例(单纯性囊肿3例、黄体囊肿3例、子宫内膜异位囊肿5例),浆液性囊腺瘤10例13个病灶,黏液性囊腺瘤8例,囊性成熟型畸胎瘤9例10个病灶,卵巢甲状腺肿10例.BOCL的大小、形态、囊壁(厚度、有无壁结节)、密度或信号、强化程度和方式等特征有助于其诊断与鉴别诊断.结论 部分BOCL的CT、MRI表现具有一定特点,术前可做出正确诊断,为临床治疗方案的选择及预后判断提供一定的理论依据.     

Incidental pancreatic cystic lesions: comparison between CT with model-based algorithm and MRI

IntroductionThe present study aims to compare low-kV CT reconstructed with MBIR technique with MRI in detecting high-risk stigmata and worrisome features in patients with pancreatic cystic lesions.MethodsWe retrospective enrolled 75 patients who underwent low-kV CT with contrast media injection for general abdominal disorders and MRI with MRCP sequences. The reviewer, blinded to clinical and histopathological data, recorded the overall number of pancreatic cystic lesions, size, location, presence of calcifications, septa, or solid enhancing or non-enhancing components, main pancreatic duct (MPD) communication, and MPD dilatation. Mean differences with 95% limits of agreement, ICC, and κ statistics were used to compare CT and MRI.ResultsMore pancreatic cystic lesions were detected with MRI than with CT, however, the ICC value of 0.81 suggested a good agreement. According to the evaluated target lesion, a very good agreement (ICC = 0.98) was found regarding the diameter (21.4 mm CT vs 21.8 mm MRI), the location (κ = 0.90), the detection of MPD dilatation (κ = 1), the presence of septa (κ = 0.86) and the MPD communication (κ = 0.87). A moderate agreement on the assessment of enhanced components was noted (κ = 0.44), while there was only a fair agreement about the presence of calcifications (κ = 0.87).ConclusionMDCT can be considered almost equivalent to MRI with MRCP in the evaluation of worrisome features and high-risk stigmata, offering detailed morphologic features helpful for their characterization.Implications for practiceEven if MRI is considered the reference standard in pancreatic cystic lesions characterization, CT can be considered a useful tool as a first-line imaging technique to identify worrisome features and high-risk stigmata.     

胰腺浆液性微囊性囊腺瘤CT和MRI表现

目的 分析胰腺浆液性微囊性囊腺瘤(SMCA)的CT和MRI影像表现特征.方法 回顾性分析经手术病理证实的17例胰腺SMCA的CT及MRI表现,包括肿瘤位置、长径、分隔、增强表现及有无钙化、中央瘢痕、胰胆管扩张等影像表现.结果 17例SMCA:1例同时行CT和MR检查,10例行CT检查,6例MR扫描(其中2例同时行MRCP).病变位于胰头2例,胰颈2例,胰腺体尾部13例.肿瘤长径1.7~14 cm,平均5.2 cm.16例可见分隔,1例分隔显示欠佳,9例可见中央瘢痕.增强扫描分隔及瘢痕强化,囊性成分均无强化.6例可见远端主胰管扩张.结论 胰腺SMCA有一定的影像学特征,多表现为分叶状结节或肿物,具有多发小囊,囊腔多<2 cm,囊与囊之间见多发纤维分隔,增强扫描后纤维分隔明显强化,但低于胰腺组织.中央瘢痕是其特征性表现,在MR上多表现为T1WI及T2WI等或稍低信号.典型的胰腺SMCA根据CT和MRI表现可以做出明确诊断.     

Preoperative evaluation of intraductal papillary mucinous tumors performed by pancreatic magnetic resonance imaging and correlated with surgical and histopathologic findings

PURPOSE: To evaluate the effectiveness of magnetic resonance imaging (MRI) in predicting the location, type of ductal involvement, and malignant transformation of intraductal papillary mucinous (IPM) pancreatic tumors made in a preoperative routine exam. MATERIALS AND METHODS: A total of 24 patients with histologic confirmation of IPM tumor (IPMT) were included in this study. The MR images obtained in operation patients were retrospectively assessed. Two radiologists who were unaware of the initial interpretations of the images independently analyzed the MRI studies and characterized the type of lesions, location, and signs of malignant transformation. Interobserver agreement was determined with weighted kappa statistics. After consensus of both radiologists, the observer performances for the MRI interpretations were compared with surgical and histologic results using weighted kappa statistics and Fisher test. RESULTS: At macroscopic examination, lesions were of combined type in 17 cases and of branch duct type in seven cases. At histologic analysis, three cases were classified as benign, three as borderline tumors, and 18 as carcinomas (eight in situ, 10 invasive). The lesions were located mainly in the head or uncinate process (N = 16) or were diffuse or multifocal (N = 2). Excellent agreement was found between the interpreters (0.90) in the evaluation of ductal involvement, good in the evaluation of lesion location (0.80) and in the diagnosis of malignant transformation (0.74). The correlation between MRI and histopathologic results was excellent in the evaluation of ductal involvement (0.90, sensitivity = 100%, specificity = 94%) and moderate in the evaluation of lesion location (0.57, sensitivity = 87%, specificity = 56%) and in the diagnosis of malignant transformation (0.60, sensitivity = 83%, specificity = 83%). CONCLUSION: MRI is an effective method of characterizing IPMT in preoperative practice. The predictive sign of IPM pancreatic tumor malignancy at MRI included only the presence of solid mass or mural nodules.     

胰管内乳头状黏液性肿瘤的CT表现与临床、病理对照

目的 探讨胰管内乳又状黏液性肿瘤的CT特点，并与临床、病理对照，提高该病的诊断正确率。方法 回顾性分析经手术病理证实的8例胰管内乳头状黏液性肿瘤的CT表现，其中男6例，女2例，平均54岁。术前8例均行CT平扫及增强检查，5例行内镜逆行胰胆管造影（ERCP）检查，8例患者亦进行了B超检查，1例行MR检查。结果 CT检查发现胰头部囊实性混合肿块6例，胰头颈体部低密度肿块1例，胰腺体积增大1例，肿块最大径5．6～9．5cm不等，增强后表现为不均匀强化，6例肿块边界尚清晰，1例病灶与胃后壁紧密粘连。8例均有不同程度的胰管扩张，无一例出现远处转移。5例ERCP检查，发现十二指肠乳头增大和黏液溢出者3例，胰头体部胰管中断1例，4例全程胰管扩张。结论 胰腺导管内乳头状黏液性肿瘤的CT表现有一定的特点；CT结合ERCP有助于该病的诊断和指导治疗。     

Detection of intraductal component around invasive breast cancer using ultrasound: correlation with MRI and histopathological findings

Purpose The purpose of this study was preoperatively to diagnose the intraductal component, which is indispensable in planning for breast conservation therapy, and also to minimize local recurrence. This study investigated the efficacy of ultrasound (US) in the detection of intraductal component in comparison with magnetic resonance imaging (MRI) and histopathological findings. Patients and Methods In 47 patients with invasive breast cancer, US features of the intraductal component were classified as (a) solid ductal dilatation radiating from the tumor, (b) presence of satellite lesion in the same segment without ductal dilatation, and (c) ductal dilatation between the main tumor and satellite lesion. MRI depicted intraductal extension as the most enhanced area during the first or second phase of the dynamic study. Other criteria for the detection of the intraductal component by MRI were as follows: (a) a satellite lesion around the main tumor, (b) bridging enhancement between the main tumor and satellite lesions. The extent of the intraductal component was measured and classified as mimimal (0–5 mm), moderate (6–15 mm) or wide (>15 mm). Results In 28 of 47 (60.0%) patients, a wide intraductal component of more than 15 mm was proved histopathologically. Of 28 patients, US and MRI could accurately detect wide intraductal components in 16 patients and 14 patients, respectively. Sensitivity, specificity, and accuracy were 57.1%, 84.2%, and 68.1% respectively for US and 50.0%, 89.5% and 65.9% for MRI, respectively. When both US and MRI results were combined, sensitivity, specificity, and accuracy were 75.0%, 84.2%, and 78.7%. Conclusion Current US examination depicted the intraductal component of breast cancer more accurately than MRI. Further, our study suggests that the use of both US and MRI together is complementary and offers more advantage than US alone. Presented as an electric poster at JRS 2005, held in Yokahama.     

Characterization of myocardial viability using MR and CT imaging

Cardiovascular magnetic resonance (MR) imaging is of proven clinical value for the noninvasive characterization of myocardial viability. Computed tomography (CT) is also being exploited for this indication. Examples of each of these imaging strategies for the assessment of myocardial viability will be provided in this review. Key MRI concepts and practical considerations such as customized MR imaging techniques and tailored imaging protocols dedicated to viability assessment are outlined with the primary focus on recent developments. Clinical applications of MR-based viability assessment are reviewed, ranging from rapid functional cine imaging to tissue characterization using T2-weighted imaging and T1-weighted late-contrast-enhanced imaging. Next, the merits and limitations of state-of-the-art CT imaging are surveyed, and their implications for viability assessment are considered. The final emphasis is on current trends and future directions in noninvasive viability assessment using MRI and CT.