Computed tomography of pancreatic pseudocysts of the duodenum

The findings of computed tomography (CT) in seven patients with pancreatic pseudocysts involving the duodenum are reported. Specific CT characteristics of duodenal wall involvement by the pseudocysts are tubular configuration of the pseudocyst, extending along the wall and conforming to the course of the duodenum (seven of seven), and abrupt flattening of the otherwise tubular or spherical pseudocyst at the border of the duodenal lumen (five of seven). The second part of the duodenum was involved in all cases; in some cases the first part of the duodenum was also involved (two of seven), and in others the pseudocyst extended to the third part of the duodenum (two of seven). All patients had other CT evidence of pancreatitis in addition to duodenal pseudocysts. CT findings are compared to other imaging methods and clinical and surgical findings. Patients with duodenal pseudocysts should be watched carefully for signs and symptoms of gastric outlet obstruction, since this was a prominent clinical problem in six of seven patients, and gastric outlet obstruction complicating suspected pancreatitis should alert to the possibility of duodenal pseudocyst.     

Pancreatic pseudocyst: comparative evaluation by sonography and computed tomography

Fifty-four patients were referred to rule out pancreatic pseudocyst. These patients underwent both sonographic and abdominal computed tomographic (CT) examinations for the evaluation of suspected pseudocysts. Among the 54 cases were 24 with proven pseudocysts. CT correctly identified 23 of the 24 pseudocysts with one false-negative and two false-positive studies. With sonography, the studies were technically inadequate in 20 of the 54 patients examined. Sonography correctly diagnosed 18 of the 24 pseudocysts; however, in 10 of these 18 cases sonographic findings were incomplete relative to CT findings. There were one false-negative and three false-positive sonographic studies. On the basis of this study, it was concluded that CT is more accurate than sonography in both diagnosing and demonstrating the extent of pseudocysts of the pancreas.     

Retained contrast after embolization of a right gastric artery pseudoaneurysm

Pseudoaneurysms due to chronic pancreatitis can be a source of major gastrointestinal (GI) hemorrhage. Computed tomography (CT) is the primary diagnostic imaging modality for pancreatic pseudocysts associated with GI bleeding can be diagnosed and embolized with transcatheter techniques once the arterial anatomy is defined. CT is a useful modality for follow-up examination of the pseudocyst; the findings must be correlated with other procedures performed on these patients. On follow-up studies, contrast medium retained in the pseudocyst after embolization may falsely signal persistent bleeding into the pseudocyts.     

Computed tomography after modified Whipple procedure with pancreatic duct occlusion

Eighty-two CT examinations performed on 28 patients who had undergone a modified Whipple procedure including pancreatic duct occlusion were reviewed. Reduction of the antero-posterior diameter of the body and tail of the pancreatic remnant was observed on consecutive scans in 8 patients (29%). Decreasing liver attenuation was seen in 4 patients (14%) postoperatively, and pseudocysts in the pancreatic remnant in 6 (21%). In 10 examinations performed because of suspected intraabdominal abscess postoperatively, abscess was diagnosed in 2 patients. In 62 routine follow-up CT examinations, significant positive findings were diagnosed in 5 patients: tumor recurrence or metastases in 4, and a large pseudocyst in one. CT is of value in the early postoperative phase to reveal postoperative complications and in the follow-up of patients with specific symptoms indicating tumor recurrence or metastases.     

Value of MR pancreatography in the evaluation of patients with chronic pancreatitis

AIM: To determine the diagnostic accuracy of magnetic resonance (MR) pancreatography and to define its role in the imaging work-up of patients with severe chronic pancreatitis. MATERIAL AND METHODS: Thirty-two patients (13 men and 19 women; 15-84 years old; mean age, 48 years) with severe chronic pancreatitis diagnosed using cross-sectional imaging, examination using contrast medium (endoscopic retrograde cholangiopancreatography, pseudocyst injection) and/or surgical findings underwent MR pancreatography performed using a two-dimensional multi-slice fast spin echo technique. All patients underwent transabdominal pancreatic sonography and computed tomography (CT) was performed in 12 patients. Two observers independently assessed the MR pancreatograms for pancreatic duct dilatation and pancreatic duct abnormalities. Compared to the final diagnosis, the accuracy of MR pancreatography in revealing complications of chronic pancreatitis was calculated and its role in the radiological work-up of patients with chronic pancreatitis evaluated. RESULTS: When compared to the final diagnosis, MR pancreatography showed the following sensitivity, specificity and diagnostic accuracy: for filling defects in pancreatic duct, 56-78%, 100% and 87-94%, respectively; for strictures, 75-88%, 92-96% and 88-94%, respectively; and for pseudocysts 100%, 100% and 100%, respectively. Filling defects were correctly diagnosed in all patients when MR pancreatography was interpreted in combination with cross-sectional imaging. Contrast pancreatography was required for the complete evaluation of strictures and communication with pseudocysts. CONCLUSION: MR pancreatography is poorly sensitive but specific in revealing pancreatic duct filling defects and strictures. However, when MR pancreatography is interpreted in combination with sonography and CT, it provides sufficient information to plan therapy in the majority of patients.     

经腹超声及术中超声在胰腺结石诊断、治疗中的应用

目的:探讨经腹超声及术中超声在胰腺结石诊断、治疗中的价值。材料和方法:对25例胰腺结石患者行经腹和术中超声检查。经腹超声主要观察胰管扩张程度,胰腺结石大小、位置,是否合并胆囊及胆道结石、胰腺假性囊肿等。术中超声观察是否有结石残留。结果:经腹超声显示25例患者主胰管扩张,胰腺实质增粗、增强。结石位于头部9例,位于全胰腺16例,伴有胆道梗阻征象13例,其中合并胆囊及胆道结石8例,并发胰腺假性囊肿3例,合并胰腺癌2例;术中超声形式显示6例未见残留结石,19例有残留结石,手术取出残留结石24枚。结论:经腹超声诊断主胰腺管结石敏感性较高,术中超声在判断残留结石及鉴别胰小管结石与胰腺实质钙化灶方面具有重要价值。     

胰腺炎并发脾门区及脾脏假性囊肿的CT诊断(附8例报告)

目的：探讨脾门区及脾脏内胰源性假性囊肿形成的解剖学机制及CT诊断价值。方法：收集经手术或临床治疗随访证实的脾及脾门区胰源性假性囊肿8例，对其CT征象进行回顾性分析。结果：8例患者胰尾或胰体尾部发现囊肿，其中5例在随访过程中发现脾内囊肿形成，2例发现脾间囊肿形成；1例单纯发现脾门区囊肿。7例早期均有明确的胰腺炎病史，发病部位以胰体尾为主，囊肿密度早期较高，后期CT值在12HU左右。壁厚薄不一，较大者壁薄。随着囊液的吸收，壁逐渐变厚。脾内囊肿初期表现边界欠清，平均7周左右出现较清晰的边界，结合增强及薄层扫描，有4例脾内囊肿与脾被囊问有明确的裂隙相连通。结论：脾肾韧带及胃脾韧带是脾门区及脾脏内胰源性假性囊肿形成的重要解剖学基础；CT检查对胰腺假性囊肿诊断及其动态监测具有重要临床意义。     

CT及MRI多模态参数对鉴别胰头部肿块型慢性胰腺炎与胰头癌的价值

目的分析胰头部肿块型慢性胰腺炎(MFCP)与胰头癌的CT以及MRI定性及定量表现,总结二者有效的影像鉴别特点。方法选取我院16例胰头部MFCP及16例胰头癌临床及影像资料进行回顾性分析。结果胰头部MFCP与胰头癌影像表现:1)肿块形态密度:分叶状(2例,11例),假性囊肿(11例,0例),肿块内钙化(6例,0例);2)DWI高信号:(2例,14例);3)静脉期相对低密度(3例,15例);ROC曲线分析示静脉期CT差值鉴别二者的AUC=0.852;4)胰胆管表现:主胰管扩张(9例,12例),胰管病灶处截断(1例,10例),胆总管扩张(6例,12例),胆总管病灶处截断(2例,10例),双管征(7例,11例),不相交征(1例,12例),肝内胆管扩张(2例,11例);5)周围组织表现:肾周筋膜增厚(9例,3例),胰周血管包绕受侵(1例,2例)。结论胰头部MFCP与胰头癌的影像学表现具有特异性,肿块的形态、DWI信号、胰胆管扩张程度及二者的血供特点有助于二者诊断及鉴别诊断。     

Indicative findings of pancreatic cancer in prediagnostic CT

We examined 20 prediagnostic CTs from 16 patients for whom the diagnosis of pancreatic cancer was delayed until full diagnostic CT was performed. Three radiologists independently reviewed the prediagnostic CTs along with 50 CTs of control subjects, including patients without pancreatic disease (n?=?38) or with chronic pancreatitis without calcification visible on CT (n?=?12). The reviewers recorded the presence of biliary or pancreatic ductal dilation, interruption of the pancreatic duct, distal parenchymal atrophy, contour abnormality and focal hypoattenuation. Frequency, sensitivity and specificity of the significant findings were calculated. Logistic regression analysis was performed. Findings indicative of pancreatic cancer were seen on 85% (17/20) of the prediagnostic CTs. Patients with pancreatic cancer were significantly (p?<?0.05) more likely to show focal hypoattenuation, pancreatic duct dilation, interruption of the pancreatic duct, and distal parenchymal atrophy, with sensitivities and specificities of 75%/84%, 50%/78%, 45%/82% and 45%/96%, respectively. Focal hypoattenuation and distal parenchymal atrophy were the independent predictors of pancreatic cancer with odds ratios of 20.92 and 11.22, respectively. In conclusion, focal hypoattenuation and pancreatic duct dilation with or without interruption, especially when accompanied by distal parenchymal atrophy, were the most useful findings for avoiding delayed diagnosis of pancreatic cancer.     

Percutaneous drainage of traumatic pancreatic pseudocysts in children

In the past, children with pancreatic pseudocysts have been managed surgically. We report seven children 3-13 years old with posttraumatic pancreatic pseudocysts who were managed with percutaneous catheter drainage. All procedures were performed with local anesthesia and intramuscular sedation under sonographic or CT guidance. Two of the pseudocysts were drained via a transgastric approach, the other five via direct transcutaneous access to the pseudocyst. The catheters were in place an average of 25 days (range, 8-66). There were no serious complications. Six patients became asymptomatic with return of the serum amylase to normal and resolution of the pseudocyst on follow-up sonograms. One patient, in whom the catheter became dislodged after 2 weeks, became asymptomatic, but he had a residual 2-cm pancreatic pseudocyst that resolved over the next 6 weeks. Our experience suggests that percutaneous drainage is a safe and effective method of treatment for traumatic pancreatic pseudocysts in children.     

Computed tomography of pancreatic abscesses

Computed tomography (CT) was used as the primary diagnostic tool in 10 cases of pancreatic abscess and seven cases of infected pseudocyst. Pancreatic gas collections were the only definitive feature of infection and were seen in five cases (29%). An equally common finding was poorly defined nonencapsulated peripancreatic fluid collections or mottled mass density. It was not possible to distinguish infected from noninfected pseudocysts or peripancreatic fluid collections by other CT criteria. Diagnostic percutaneous needle aspiration is indicated in patients with pancreatic pseudocyst or fluid collections with persistent fever or leukocytosis. CT is also useful in the preoperative evaluation of multiple abscesses and of recurrent abscesses after surgery.     

Detectability of pancreas divisum in patients with acute pancreatitis on multi-detector row computed tomography

The purpose of this study was to retrospectively assess the diagnostic performance of multi-detector row computed tomography (MDCT) in an evaluation of pancreas divisum using endoscopic retrograde pancreatography (ERP) as the reference standard. We analyzed 41 consecutive patients (14 cases of pancreas divisum and 27 cases of standard anatomy) who had undergone both MDCT and ERP for the evaluation of clinically diagnosed acute pancreatitis between November 2004 and June 2007. The CT reconstruction thickness and interval were both 3 mm. Two radiologists independently reviewed CT data, and the diagnostic confidence in determining the pancreatic ductal anatomy was scored using a five-point scale. CT detectability was correlated with the severity of pancreatitis and the degree of pancreatic necrosis based on the Balthazar index. With consensus, 16 of 41 cases (39.0%) were evaluated as indeterminate. Ductal anatomy was correctly diagnosed in 23 of 41 cases (56.1%). Eight of 14 cases (57.1%) were correctly diagnosed as pancreas divisum. Standard anatomy was identified in 15 of 27 cases (55.6%). The inter-observer agreement was substantial (κ = 0.71). Grade B or more pancreatitis and the presence of pancreatic necrosis significantly influenced the evaluation of ductal anatomy (p = 0.01 and p < 0.01, respectively). Pancreas divisum was correctly diagnosed in the case of grade A acute pancreatitis. The CT detectability of pancreas divisum in patients with grade B or more pancreatitis is still relatively low even in the MDCT era.     

Pancreatic ductal adenocarcinoma: a radiomics nomogram outperforms clinical model and TNM staging for survival estimation after curative resection

To identify a CT-based radiomics nomogram for survival prediction in patients with resected pancreatic ductal adenocarcinoma (PDAC). A total of 220 patients (training cohort n = 147; validation cohort n = 73) with PDAC were enrolled. A total of 300 radiomics features were extracted from CT images. And the least absolute shrinkage and selection operator algorithm were applied to select features and develop a radiomics score (Rad-score). The radiomics nomogram was constructed by multivariate regression analysis. Nomogram discrimination, calibration, and clinical usefulness were evaluated. The association of the Rad-score and recurrence pattern in PDAC was evaluated. The Rad-score was significantly associated with PDAC patient’s disease-free survival (DFS) and overall survival (OS) (both p < 0.001 in two cohorts). Incorporating the Rad-score into the radiomics nomogram resulted in better performance of the survival prediction than that of the clinical model and TNM staging system. In addition, the radiomics nomogram exhibited good discrimination, calibration, and clinical usefulness in both the training and validation cohorts. There was no association between the Rad-score and recurrence pattern. The radiomics nomogram integrating the Rad-score and clinical data provided better prognostic prediction in resected PDAC patients, which may hold great potential for guiding personalized care for these patients. The Rad-score was not a predictor of the recurrence pattern in resected PDAC patients. • The Rad-score developed by CT radiomics features was significantly associated with PDAC patients’ prognosis. • The radiomics nomogram integrating the Rad-score and clinical data has value to permit non-invasive, low-cost, and personalized evaluation of prognosis in PDAC patients. • The radiomics nomogram outperformed clinical model and the TNM staging system in terms of survival estimation.     

Abdominal cerebrospinal fluid pseudocyst

A case of an abdominal cerebrospinal fluid (CSF) pseudocyst in a patient with a ventriculoperitoneal shunt is reported to illustrate this known but rare complication. In the setting of a VP shunt, the frequency of abdominal CSF pseudocyst formation is approximately 3.2%, often being precipitated by a recent inflammatory or infective process or recent surgery. Larger pseudocysts tend to be sterile, whereas smaller pseudocysts are more often infected. Ultrasound and CT each have characteristic findings.     

Differentiating Pancreatic Ductal Adenocarcinoma from Pancreatic Serous Cystadenoma, Mucinous Cystadenoma, and a Pseudocyst with Detailed Analysis of Cystic Features on CT Scans: a Preliminary Study

Objective

To determine whether or not detailed cystic feature analysis on CT scans can assist in the differential diagnosis of pancreatic ductal adenocarcinoma (PDAC) from serous cystadenoma (SCN), mucinous cystadenoma (MCN), and a pseudocyst.

Materials and Methods

This study received Institutional Review Board approval and informed patient consent was waived. Electronic radiology and pathology databases were searched to identify patients with PDAC (n = 19), SCN (n = 26), MCN (n = 20) and a pseudocyst (n = 23) who underwent pancreatic CT imaging. The number, size, location, and contents of cysts, and the contour of the lesions were reviewed, in addition to the wall thickness, enhancement patterns, and other signs of pancreatic and peripancreatic involvement. Diagnosis was based on lesion resection (n = 82) or on a combination of cytological findings, biochemical markers, and tumor markers (n = 6). Fisher''s exact test was used to analyze the results.

Results

A combination of the CT findings including irregular contour, multiple cysts, mural nodes, and localized thickening, had a relatively high sensitivity (74%) and specificity (75%) for differentiating PDAC from SCN, MCN, and pseudocysts (p < 0.05). Other CT findings such as location, greatest dimension, or the presence of calcification were not significantly different.

Conclusion

The CT findings for PDAC are non-specific, but perhaps helpful for differentiation. PDAC should be included in the general differential diagnosis of pancreatic cystic neoplasms.     

胰腺炎并发网膜囊脾隐窝及胃脾韧带区假性囊肿的CT诊断

目的:探讨网膜囊脾隐窝及胃脾韧带区胰源性假性囊肿形成的解剖学基础、病理机制及CT诊断价值。材料和方法:回顾性分析15例网膜囊及胃脾韧带区胰源性假性囊肿的CT征象。结果:8例网膜囊区假性囊肿有2例延伸到网膜囊脾隐窝,6例胃脾韧带区假性囊肿均与脾门、胰尾部病变有联系,1例为胰周多发囊肿。结论:脾肾韧带及胃脾韧带的连续性是胃脾韧带区胰源性假性囊肿形成的解剖学基础;囊肿与脾门是否连续是鉴别网膜囊脾隐窝与胃脾韧带区胰源性假性囊肿的重要依据;CT检查对胰源性假性囊肿的诊断、定位及其动态监测具有重要临床意义。     

胰腺导管内乳头状黏液性肿瘤的CT诊断

目的:探讨胰腺导管内乳头状黏液性肿瘤(IPMN)的螺旋CT诊断价值。材料和方法:回顾性分析经手术病理证实的14例胰腺IPMN的螺旋CT表现。结果:主胰管型IPMN3例,表现为主胰管扩张伴管壁结节样突起;分支胰管型IPMN5例,表现为分叶状单发囊性病变或葡萄串样多发囊性病变伴腔内分隔或结节样突起;混合型IPMN6例,表现为主胰管扩张和囊性病变合并存在。CT诊断IPMN恶变6例,病理诊断导管内乳头状黏液腺癌7例。结论:螺旋CT能够显示胰腺IPMN的病理特征,并可做出分型。     

Lymphocele Mimicking a Pancreatic Pseudocyst: Imaging Characteristics and Percutaneous Management

Lymphocele can be a difficult diagnosis to establish and may be confused for other abdominal fluid collections. Conversely, pancreatic pseudocysts may occur inadvertently from upper abdominal surgery and must be included in the differential diagnosis of virtually all peripancreatic fluid collections. We report the unusual occurrence of an unsuspected postoperative peripancreatic lymphocele that was thought to be a pancreatic pseudocyst. In retrospect, CT findings were evident and diagnostic. The lymphocele responded well to percutaneous drainage.     

CT findings in silicosis due to denim sandblasting

The purpose of this study was to describe the findings of CT performed on denim sandblasters with silicosis. Fifty consecutive male patients with silicosis were evaluated. Their clinical data and pulmonary function tests (PFT) were obtained. The CT findings were recorded and the correlations between CT nodular profusion score and the other parameters were assessed. The diagnoses of the patients were classified as accelerated silicosis (n = 43) and acute silicosis (n = 7). The most common CT finding was centrilobular nodules. Twenty-three patients had complicated silicosis based on pleural involvement and presence of progressive massive fibrosis (PMF). Lymphadenopathy (LAP) was positive in 50% of the patients, with calcification in 24%. The CT grade was highly correlated with the clinical data such as exposure duration and PFT. Our findings suggest that the clinical manifestation of silicosis in denim sandblasters is severe. Although the duration of exposure is shorter the rate of complicated silicosis patients with pleural involvement was unexpectedly higher in the cases. Because the most common radiological appearance was nodules and the CT grading of the nodules was highly correlated with the clinical data, nodule grading may be used in the management of such cases.     

Tuberculous adenitis: comparison of CT and MRI findings with histopathological features

Our aim was to investigate the relationship between the various histopathological features and the CT and MRI findings in routinely submitted histopathological specimens for the diagnosis of tuberculous lymphadenopathy. Twelve formalin-fixed, paraffin-embedded tissue blocks from ten patients who were clinically suspected of having tuberculous lymphadenopathy were evaluated. We assessed the presence of histopathological features including granuloma formation, caseous necrosis, and presence of Langhans-type giant cells, calcifications, fibrosis or normal lymphoid tissue. We performed polymerase chain reaction (PCR)-based assay for mycobacterial DNA and Ziehl-Neelsen staining for acid-fast bacilli (AFB). Findings were compared with those of CT and MRI, including signal intensities on unenhanced MR images, lymph node homogeneity, attenuation values on contrast-enhanced CT and enhancement patterns on MRI. Based on CT and MRI findings, four lymph node types could be defined: (1) homogeneous nodes, visible on both pre- and post-contrast images and corresponding histopathologically to granulation tissue without or with minimal caseation necrosis (n = 2); (2) heterogeneous nodes, showing heterogeneous enhancement patterns with central non-enhancing areas and corresponding to minor or moderate intranodal caseation/liquefaction necrosis (n = 3); (3) nodes showing peripheral rim enhancement and corresponding to moderate or extensive intranodal caseation/liquefaction necrosis (n = 5); (4) heterogeneous nodes showing intranodal hyperdensities on CT and hypointense areas on T1- and T2-weighted images and corresponding to fibrosis and calcifications (n = 2). On CT and MRI, the findings reflect different stages of the tuberculous process. Imaging findings depend on the presence and the degree of granuloma formation, caseation/liquefaction necrosis, fibrosis and calcifications.