Assessment of main pancreatic duct cutoff with dilatation, but without visible pancreatic focal lesion on MDCT: a novel diagnostic approach for malignant stricture using a CT-based nomogram.

OBJECTIVES: To identify useful features to predict hidden pancreatic malignancies in patients with main pancreatic duct (MPD) abrupt cutoff and dilatation, but without visible focal pancreatic lesions on CT. METHODS: This retrospective study included 92 patients (mean age, 63.4 ± 10.6 years, 63 men and 29 women) with MPD abrupt cutoff and dilatation, but without visible focal pancreatic lesion on contrast-enhanced CT between 2009 and 2021. Two radiologists independently evaluated the CT imaging features. Multivariable logistic regression analysis was performed to identify clinical and CT imaging features for hidden pancreatic malignancies. A nomogram was developed based on these results and assessed its performance. RESULTS: Thirty-eight (41.3%) and 54 (58.7%) were classified into the malignant and benign groups, respectively. In the multivariable analysis, CA19-9 elevation (odds ratio [OR] 7.5, p = 0.003), duct cutoff site at the head/neck (OR 7.6, p = 0.006), parenchymal contour abnormality at the duct cutoff site (OR 13.7, p < 0.001), and presence of acute pancreatitis (OR 11.5, p = 0.005) were independent predictors of pancreatic malignancy. A combination of any two significant features showed an accuracy of 77.2%, and a combination of any three features exhibited a specificity of 100%. The CT-based nomogram showed an area under the curve (AUC) of 0.84 (95% confidence interval, 0.77-0.90). CONCLUSIONS: The three CT imaging features and CA19-9 elevation translated into a nomogram permit a reliable estimation of hidden pancreatic malignancies in patients with MPD abrupt cutoff without visible focal pancreatic lesion. It may facilitate determining whether to proceed to further diagnostic tests. KEY POINTS: • Isoattenuating pancreatic ductal adenocarcinoma can manifest only as an isolated main pancreatic duct (MPD) dilatation with abrupt cutoff, making it difficult to distinguish from benign strictures. • Along with the serum CA 19-9 elevation, MPD cutoff site at the pancreas head or neck, parenchymal contour abnormality at the duct cutoff site, and associated acute pancreatitis indicated a higher probability of the malignant MPD strictures. • The CT-based nomogram provided excellent diagnostic performance (AUC of 0.84) for hidden pancreatic malignancies in patients with MPD abrupt cutoff and dilatation.

Assessment of malignant potential in intraductal papillary mucinous neoplasms of the pancreas using MR findings and texture analysis.

OBJECTIVES: To investigate the utility of MR findings and texture analysis for predicting the malignant potential of pancreatic intraductal papillary mucinous neoplasms (IPMNs). METHODS: Two hundred forty-eight patients with surgically confirmed IPMNs (106 malignant [invasive carcinoma/high-grade dysplasia] and 142 benign [low/intermediate-grade dysplasia]) and who underwent magnetic resonance imaging (MRI) with MR cholangiopancreatography (MRCP) were included. Two reviewers independently analyzed MR findings as proposed by the 2017 international consensus guidelines. Texture analysis of MRCP was also performed. A multivariate logistic regression analysis was used to identify predictors for malignant IPMNs. Diagnostic performance was also analyzed using receiver operating curve analysis. RESULTS: Among MR findings, enhancing mural nodule size ≥ 5 mm, main pancreatic duct (MPD) ≥ 10 mm or MPD of 5 to 9 mm, and abrupt change of MPD were significant predictors for malignant IPMNs (p < 0.05). Among texture variables, significant predictors were effective diameter, surface area, sphericity, compactness, entropy, and gray-level co-occurrence matrix entropy (p < 0.05). At multivariate analysis, enhancing mural nodule ≥ 5 mm (odds ratios (ORs), 6.697 and 6.968, for reviewers 1 and 2, respectively), MPD ≥ 10 mm or MPD of 5 to 9 mm (ORs, 4.098 and 4.215, and 2.517 and 3.055, respectively), larger entropy (ORs, 1.485 and 1.515), and smaller compactness (ORs, 0.981 and 0.977) were significant predictors for malignant IPMNs (p < 0.05). When adding texture variable to MR findings, diagnostic performance for predicting malignant IPMNs improved from 0.80 and 0.78 to 0.85 and 0.85 in both reviewers (p < 0.05), respectively. CONCLUSIONS: MRCP-derived texture features are useful for predicting malignant IPMNs, and the addition of texture analysis to MR features may improve diagnostic performance for predicting malignant IPMNs. KEY POINTS: • Among the MR imaging findings, an enhancing mural nodule size ≥ 5 mm and dilated main pancreatic ducts are independent predictors for malignant IPMNs. • Greater entropy and smaller compactness on MR texture analysis are independent predictors for malignant IPMNs. • The addition of MR texture analysis improved the diagnostic performance for predicting malignant IPMNs from 0.80 and 0.78 to 0.85 and 0.85, respectively.

COMPLEX VISUAL ASSESSMENT OF STRUCTURAL CHANGES IN PANCREAS IN THE PATIENTS WITH CHRONIC PANCREATITIS.

Chronic pancreatitis is one of the leading gastroenterologic disorders which is characterised by polymorphism of clinical manifestations, polyetiologic course and, usually, polymorbidity. The presence of such a combination of signs makes both diagnosis and treatment more difficult. This is why nowadays it is necessary to use a range of clinical, laboratory and instrumental methods of a diagnostic endeavour in order to make a diagnosis and determine the state of the pancreas. The aim of this study - to investigate and analyse structural changes in the pancreas in chronic pancreatitis in the anamnestic and clinical dimensions. In the present study, in order to achieve our aim 102 patients with chronic pancreatitis underwent general physical and laboratory examination. All the patients experienced hypertension II as a comorbid condition. In the formed group, female patients prevailed (55,9%) with the average age being 51,0±10,0 years. The duration of chronic pancreatitis was within a range of 7,0±3,0 years, whereas the hypertension duration range was 5,0±2,0 years. The following instrumental examination procedures were performed: sonographic examination of the abdominal cavity, esophagogastroduodenoscopy, duodenal drainage and endoscopic retrograde cholangiopancreatography (ERCP). Apart from hypertension, the patients with chronic pancreatitis belonging to the treatment group were diagnosed with other morphological and functional disorders related to the endocrine system, the digestive system and cardiovascular system which were revealed with the use of additional laboratory and instrumental methods. When the clinical picture was assessed on admission to hospital, all the patients presented with pain dyspeptic syndrome and exocrine pancreatic insufficiency in different proportions. 12 patients with chronic pancreatitis, whose clinical picture showed a marked pain abdominal syndrome, the intensity of which did not subside during 3 weeks of background therapy, and the absence of dynamic changes according to the ultrasound examination of the pancreas, underwent the additional diagnostic procedure ERCP to identify structural changes of the pancreatic ducts and parenchymatous parameters of the pancreas. The findings were as follows: the signs of the dilation of the major pancreatic duct were identified in all examined patients (100%), which did not coincide with the data provided by the ultrasound examination; the dilation of the small pancreatic ducts was found in 2 (16,7%) patients, lithiasis of Wirsung's duct in 3 (25,0%) patients; the combination of cystic transformation and calcinosis of the major pancreatic duct in 1 patient (8,4%); and cystic transformation in combination with the dilation of the duct of Wirsung in 2 (16,7%) patients. The imaging of structural changes in the pancreas requires the combination of instrumental and diagnostic methods, in particular EGD and ultrasound examination, as well as ERCP in order to make accurate assessment of the pancreatic ducts and parenchymatous parameters of the pancreas in case of a relapsing course of disease. The analysis of the identified disorders of the pancreatic ducts and parenchyma makes it possible to adjust treatment protocols to provide proper clinical care to patients with chronic pancreatitis.

Endoscopic Ultrasound Assessment of Pancreatic Duct Diameter Predicts Neuroendocrine Tumors and Other Pancreas Masses.

OBJECTIVES: Distinguishing neuroendocrine tumors (NETs) and other pancreas lesions from adenocarcinomas via endoscopic ultrasound (EUS) requires additional tissue for special staining and processing. Our aim was to determine if main pancreatic duct (PD) diameter on EUS helps to differentiate NET and other unusual tumors from adenocarcinoma. METHODS: We evaluated 30 consecutive patients diagnosed with NET or other pancreas lesions by EUS with 90 matched patients who were found to have adenocarcinoma. Dilated PD was defined as greater than 3 mm. Multivariate logistic regression was used to evaluate associations between lesion type and PD diameter. RESULTS: Among the 30 patients with NET/other pancreas lesions, 21 had NETs, 7 had metastases, and 2 had lymphomas. A dilated PD was demonstrated in only 3.3% of pancreatic NET/other lesions but present in 88.9% of cases of primary adenocarcinoma (P < 0.01). In multivariate analysis, a normal PD diameter and absence of clinical symptoms strongly predicted the presence of pancreatic NET/other versus adenocarcinoma (P < 0.01). CONCLUSIONS: The absence of PD dilation upstream of the lesion suggests NET or other lesions rather than adenocarcinoma. This finding should prompt endosonographers to obtain additional tissue at the time of EUS to send for special studies.

Uptodate in the assessment and management of intraductal papillary mucinous neoplasms of the pancreas.

Intraductal Papillary Mucinous Neoplasms (IPMNs) are the most common cystic tumors of the pancreas and are considered premalignant lesions. IPMNs are characterized by the papillary growth of the ductal epithelium with rich mucin production, which is responsible for cystic segmental or diffuse dilatation of the main pancreatic duct (MPD) and/or its branches. According to the different involvement of pancreatic duct system, IPMNs are divided into main duct type (MD-IPMN), branch duct type (BD-IPMN), and mixed type (MT-IPMN). IPMNs may be incidentally discovered in asymptomatic patients, particularly in those with BD-IPMNs, when imaging studies are performed for unrelated indications. The increase in their frequency may reflect the combined effects of new diagnostic techniques, the improvement of radiologic exams and progress in the recognition of the pathology. MD-IPMNs present a higher risk of malignant progression than BD-IPMNs; as a consequence, all the guidelines strictly suggest the need of surgery for MD- and MT- IPMNs with MPD > 10 mm, while the management of BD-IPMNs is still controversial and depends on several cysts and patients features. The choice between non-operative and surgical management depends on the distinction between benign and invasive IPMN forms, assessment of malignancy risk, patient's wellness and its preferences. This manuscript revises the different guidelines for the management of IPMNs that have been published in different world countries: the international (Sendai 2006 and Fukuoka 2012), the 2013 European, the 2014 Italian, and finally the 2015 American guidelines. In summary, this review will integrate the recent insights in the combination of diagnostic techniques, such as Magnetic Resonance Imaging (MRI) and endoscopic ultrasound (EUS), pathology classification, and management of IPMNs.

Comparison of endoscopic ultrasound, computed tomography and magnetic resonance imaging in assessment of detailed structures of pancreatic cystic neoplasms.

AIM: To evaluate the advantages of endoscopic ultrasound (EUS) in the assessment of detailed structures of pancreatic cystic neoplasms (PCNs) compared to computed tomography (CT) and magnetic resonance imaging (MRI). METHODS: All patients with indeterminate PCNs underwent CT, MRI, and EUS. The detailed information, including size, number, the presence of a papilla/nodule, the presence of a septum, and the morphology of the pancreatic duct of PCNs were compared among the three imaging modalities. The size of each PCN was determined using the largest diameter measured. A cyst consisting of several small cysts was referred to as a mother-daughter cyst. Disagreement among the three imaging modalities regarding the total number of mother cysts resulted in the assumption that the correct number was the one in which the majority of imaging modalities indicated. RESULTS: A total of 52 females and 16 males were evaluated. The median size of the cysts was 42.5 mm by EUS, 42.0 mm by CT and 38.0 mm by MRI; there was no significant difference in size as assessed among the three imaging techniques. The diagnostic sensitivity and ability of EUS to classify PCNs were 98.5% (67/68) and 92.6% (63/68), respectively. These percentages were higher than those of CT (73.1%, P < 0.001; 17.1%, P < 0.001) and MRI (81.3%, P = 0.001; 20.3%, P < 0.001). EUS was also able to better assess the number of daughter cysts in mother cysts than CT (P = 0.003); however, there was no significant difference between EUS and MRI in assessing mother-daughter cysts (P = 0.254). The papilla/nodule detection rate by EUS was 35.3% (24/68), much higher than those by CT (5.8%, 3/52) and MRI (6.3%, 4/64). The detection rate of the septum by EUS was 60.3% (41/68), which was higher than those by CT (34.6%, 18/52) and by MRI (46.9%, 30/64); the difference between EUS and CT was significant (P = 0.02). The rate of visualizing the pancreatic duct using EUS was 100%, whereas using CT and MRI it was less than 10%. CONCLUSION: EUS helps visualize the detailed structures of PCNs and has many advantages over CT and MRI. EUS is valuable in the diagnosis and assessment of PCNs.

Pancreaticobiliary Juice Reflux in Patients With a Morphologically Normal Ductal System: Assessment Using Unenhanced MRI With Spin Labeling.

OBJECTIVE: The purpose of this article is to evaluate pancreaticobiliary reflux and to assess its correlation with clinical findings in patients without morphologic pancreaticobiliary maljunction by using a new MRI technique. MATERIALS AND METHODS: A total of 320 consecutive patients with suspected pancreaticobiliary diseases underwent MRCP and flow analysis by MRI. MRI flow analysis, clinical, and laboratory findings of each patient were retrospectively reviewed. The visible pancreaticobiliary reflux was graded on a 5-point confidence scale. RESULTS: Among all 320 patients with pancreatic juice reflux, 14.1% had reflux scored as grades 4 and 5 combined, and 5.0% had reflux scored as grade 5. By univariate analysis and multivariate analysis, a relatively long common channel was found to be the only significant causal factor for pancreatic juice reflux. Of patients with pancreatic juice reflux of grade 4 or 5, 11.1% (5/45) also had biliary malignancies; 18.8% (3/16) of those with pancreatic juice reflux of grade 5 had biliary malignancies. Conversely, pancreatic juice reflux of grade 4 or 5 occurred in 35.7% (5/14) of patients with biliary malignancies, and reflux of grade 5 occurred in 21.4% (3/14) of those patients. CONCLUSION: It was possible to evaluate pancreaticobiliary reflux using an MRI technique that may be suitable as a screening tool. Our results revealed that pancreaticobiliary reflux is relatively frequent in individuals without pancreaticobiliary maljunction.

Missed pancreatic ductal adenocarcinoma: Assessment of early imaging findings on prediagnostic magnetic resonance imaging.

OBJECTIVE: To investigate the early imaging findings and growth rate of pancreatic ductal adenocarcinoma (PDAC), and to assess whether MR imaging detects early PDAC better than CT. MATERIALS AND METHODS: The institutional review board approved this retrospective study and waived the requirement for informed consent. Twenty-two patients were included, and two radiologists, by consensus, assessed the presence of focal lesions, interruption of the main pancreatic duct (MPD), MPD dilatation, and pancreatitis, volume doubling time (VDT) of PDAC on prediagnostic MR imaging. Two other observers independently reviewed three image sets (CT images, unenhanced MR images, and unenhanced and contrast-enhanced MR images) for the detection of early PDAC. Paired Wilcoxon signed rank test and receiver operating characteristic (ROC) curve analysis were used for statistical analyses. RESULTS: In 20 (90.9%) patients, prediagnostic MR exams showed abnormality, and all of them showed focal lesions on the first abnormal prediagnostic MR exams. Thirteen lesions (65%) showed no MPD interruption and one lesion (5%) was accompanied by pancreatitis. The mean VDT of PDAC was 151.7 days (range, 18.3-417.8 days). Diagnostic performance of unenhanced MR images (Az, 0.971-0.989) and combined unenhanced and contrast-enhanced MR images (Az, 0.956-0.963) was significantly better than that of CT images (Az, 0.565-0.583; p<0.01) for both observers, CONCLUSION: The most common early imaging finding of PDAC on prediagnostic MR exams was a focal lesion with no MPD interruption with a mean volume doubling time of five months. MR imaging was superior to CT for the detection of early PDAC.

CT and MRI assessment of symptomatic organized pancreatic fluid collections and pancreatic duct disruption: an interreader variability study using the revised Atlanta classification 2012.

PURPOSE: Compare CT and MRI for fluid/debris component estimate and pancreatic duct (PD) communication with organized pancreatic fluid collections in acute pancreatitis. Evaluate fat density globules on CT as marker for debris. METHODS: 29 Patients with 46 collections with CECT and MRI performed ≥4 weeks of symptom onset assessed for necrotizing pancreatitis, estimated percentage of fluid volume and PD involvement by two radiologists on separate occasions. T2WI used as standard for estimated percentage of fluid volume. Presence of fat globules and fluid attenuation on CT was recorded. Spearman rank correlation and kappa statistics were used to assess the correlation between imaging techniques and interreader agreement, respectively. RESULTS: Necrotizing pancreatitis seen on CT in 27 (93%, κ 0.119) vs. 20 (69%, κ 0.748) patients on MRI. CT identified 42 WON and 4 pseudocysts vs. 34 WON, and 12 pseudocysts on MRI. Higher interreader agreement for percentage fluid volume on MRI (κ = 0.55) vs. CT (κ = 0.196). Accuracy of CT in evaluation of percentage fluid volume was 65% using T2WI MRI used as standard. Fat globules identified on CT in 13(65%) out of 20 collections containing <75% fluid vs. 4(15%) out of 26 collections containing >75% fluid (p = 0.0001). PD involvement confidently excluded on CT in 68% collections vs. 93% on MRI. CONCLUSION: MRI demonstrates higher reproducibility for fluid to debris component estimation. Fat globules on CT were frequently seen in organized pancreatic fluid collections with large amount of debris. PD disruption more confidently excluded on MRI. This information may be helpful for pre-procedure planning.

Correlation between preoperative imaging and intraoperative risk assessment in the prediction of postoperative pancreatic fistula following pancreatoduodenectomy.

BACKGROUND: Prediction of postoperative pancreatic fistula (POPF) can be carried out with the intraoperative assessment of pancreatic consistency (PC) and via pancreatic duct width (iPDW). Preoperative computed tomography (CT) calculated pancreatic remnant volume (PRV) and duct width (rPDW) have also been shown to offer useful information about the risk of POPF. OBJECTIVE: The objective of this study was to determine the predictive value of the preoperative radiological features as compared with the intraoperative risk estimation for the subsequent development of POPF. METHOD: All patients undergoing pancreatoduodenectomy between September 2007 and March 2012 at the Karolinska University Hospital Stockholm were included. PRV and rPDW were determined on preoperative CT and in parallel, intraoperative PC and iPDW of the remnant pancreas were independently assessed. RESULTS: A total of 296 consecutive pancreatoduodenectomies were included. POPF occurred in 45 patients (15.2 %). Of those with a preoperatively calculated PRV < 23.0 cm(3), 2.8 % developed POPF compared with 25.7 % of those with a corresponding volume > 46.0 cm(3). In patients with an rPDW > 7.0 mm, 4.1 % had a POPF as compared with 38.7 % for those with rPDW < 2.0 mm. The POPF risk estimates based on PRV and rPDW and the intraoperative risk assessments were found to be identical (p < 0.001). In the receiver operating characteristic analysis, area under the curve was 0.80 (95 % confidence interval [CI] 0.72-0.87) and 0.80 (95 % CI 0.72-0.88) for the CT-based and intraoperative risk prediction models, respectively. CONCLUSIONS: Preoperative CT-based and intraoperative gland risk assessments offer comparable predictive information on the risk of POPF after pancreatoduodenectomy. These results imply that accurate POPF risk estimation can be carried out in the preoperative setting to opt for improved patient selection into relevant research protocols and the availability of surgical expertise and techniques.

Autoimmune pancreatitis: assessment of the enhanced duct sign on multiphase contrast-enhanced computed tomography.

PURPOSE: To assess the usefulness of the computed tomography (CT) finding of main pancreatic duct (MPD) wall enhancement, termed the "enhanced duct sign", for diagnosis of autoimmune pancreatitis (AIP) in comparison with diagnosis of pancreatic carcinoma and chronic pancreatitis. MATERIALS AND METHODS: Two radiologists independently evaluated the presence or absence of the enhanced duct sign on multiphase contrast-enhanced CT in patients with AIP (n=55), pancreatic carcinoma (n=50), and chronic pancreatitis (n=50). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of AIP were calculated. In patients demonstrating the enhanced duct sign, additional findings were evaluated by consensus. RESULTS: The enhanced duct sign was more frequently observed in patients with AIP (37/55, 67%) than in patients with pancreatic carcinoma (5/50, 10%) or chronic pancreatitis (0/50, 0%) (P<0.05). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the finding were 0.67, 0.95, 0.85, 0.88, and 0.84, respectively. In AIP, the lumen within the enhanced duct was completely or partially invisible in 29 of 37 (78%) patients, and the enhanced duct was observed within the affected pancreatic parenchyma in 35 of 37 (95%) patients. In pancreatic carcinoma, the lumen within the enhanced duct was visible in all patients (5/5, 100%), and the enhanced duct was observed downstream of the tumor (5/5, 100%). CONCLUSION: The enhanced duct sign is highly specific of AIP.

Autoimmune pancreatitis: disease evolution, staging, response assessment, and CT features that predict response to corticosteroid therapy.

PURPOSE: To evaluate the evolution of morphologic features of autoimmune pancreatitis (AIP) at computed tomography (CT) and to identify imaging features that can predict AIP response to corticosteroid therapy (CST). MATERIALS AND METHODS: This HIPAA-compliant retrospective study had institutional review board approval. From among a cohort of 63 patients with AIP, 15 patients (12 men, three women; mean age, 64.7 years; age range, 30-84 years) who underwent sequential CT examinations before treatment were included to assess the evolution of disease by reviewing pancreatic, peripancreatic, and ductal changes. Of these patients, 13 received CST and underwent posttreatment CT; these CT studies were evaluated to determine if there were imaging features that could predict response to CST. RESULTS: The disease evolved from changes of diffuse (14 of 15 patients) or focal (one of 15 patients) parenchymal swelling, peripancreatic stranding (10 of 15 patients), "halo" (nine of 15 patients), pancreatic duct changes (15 of 15 patients), and distal common bile duct narrowing (12 of 15 patients) to either resolution or development of ductal strictures and/or focal masslike swelling. In 13 patients treated with CST, favorable response to treatment was seen in those with diffuse pancreatic and peripancreatic changes. Suboptimal response was seen in patients with ductal stricture formation (two of 13 patients) and in those in whom focal masslike swellings persisted after resolution of diffuse changes (seven of 13 patients). CONCLUSION: CT features like diffuse swelling and halo respond favorably to CST and likely reflect an early inflammatory phase, whereas features like ductal strictures and focal masslike swelling are predictive of a suboptimal response and symbolize a late stage with predominance of fibrosis.

Intraductal ultrasonography for the assessment of preoperative biliary and pancreatic strictures.

Diseases of the biliary and pancreatic ducts are often difficult to diagnose. Although transcutaneous ultrasonography, computer tomography and magnetic resonance greatly improved in performance, two major problems have not been completely solved yet: first, the differentiation of malignant and benign bile duct strictures, and, second, the assessment of the resectability of carcinomas underlying biliary strictures. Ultrasound probes can be inserted through the working channel of the duodenoscope and passed selectively both into the biliary and pancreatic ducts. Ultrasound frequencies of 20 or 30 MHz enable a penetration of up to 2 cm and a resolution of 0.07 to 0.18 mm. The main clinical indication for intraductal ultrasonography of the biliary tract is obstructive jaundice, which requires assessment of bile duct strictures and local tumor staging. Miniprobes can contribute to the differential diagnosis of strictures localized in the main pancreatic duct, and also to localizing small endocrine tumors. Small tumors of the papilla of Vater can be staged before a possible endoscopic resection. Feasibility of the method is excellent in expert hands with almost no added morbidity.

Small prophylactic pancreatic duct stents: an assessment of spontaneous passage and stent-induced ductal abnormalities.

BACKGROUND AND STUDY AIMS: Placing small stents in the pancreatic duct at endoscopic retrograde cholangiopancreatography reduces the risk of pancreatitis. However, this practice means that a second procedure might be required to remove the stent, and stents can also damage the duct. The aims of this study were to determine the frequency of spontaneous dislodgment and to assess the incidence of stent-induced ductal irregularities. PATIENTS AND METHODS: We performed a retrospective analysis of consecutive patients seen over a 3-year period (2001 - 2004) who had undergone placement of a 3-Fr pancreatic duct stent and in whom the fate of the stent had been documented. Radiographs were reviewed to determine stent passage at 30 days. If applicable, follow-up pancreatograms were reviewed to assess for stent-induced ductal abnormalities. Statistical analysis was performed using chi-squared and Fisher's exact tests for proportions, and 95 % binomial confidence intervals (CI) were calculated. RESULTS: Records for 125 consecutive patients who had had 3-Fr pancreatic stents placed were reviewed. The stents had passed spontaneously within 30 days in 110/125 patients (88 %). In the remaining 15 patients (12 %, 95 % CI 6.9 % - 19 %), the stents were still present on follow-up radiographs after a median time of 36 days, (range 31 - 116 days). Stent length, pancreatic sphincterotomy, and pancreas divisum had no effect on the likelihood of spontaneous passage. No stent-induced ductal irregularities were observed. CONCLUSIONS: Nearly 90 % of prophylactic 3-Fr pancreatic duct stents pass spontaneously within 30 days, and these stents were not observed to induce changes in the pancreatic duct.

Assessment of anomalous pancreaticobiliary ductal junction with high-resolution multiplanar reformatted images in MDCT.

OBJECTIVE: The objective of our study was to assess the capabilities of MDCT for the diagnosis of an anomalous pancreaticobiliary ductal junction using high-resolution multiplanar reformatted (multiplanar reconstruction) images. MATERIALS AND METHODS: This study included nine patients with and 54 without an anomalous pancreaticobiliary ductal junction confirmed on direct cholangiopancreatography. Multiplanar reconstruction images with 0.5-mm continuous slices were generated from isotropic or nearly isotropic pancreatic phase images. By mainly interpreting the multiplanar reconstruction images using the Scrolling mode, two blinded reviewers independently determined whether the confluence of the pancreatic and biliary ducts joined in the pancreatic parenchyma (in other words, outside the duodenal wall). The results were correlated with the findings of direct cholangiopancreatography. The diagnostic capabilities of CT for revealing associated pancreatobiliary diseases were assessed in patients with this anomaly. RESULTS: Interobserver agreement in the classification of the duct confluence was high (kappa = 0.804). The duct confluence was identified in all patients except four without an anomalous pancreaticobiliary ductal junction. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CT for diagnosing an anomalous pancreaticobiliary ductal junction were 100% (9 of 9 patients), 87% (47 of 54 patients), 89% (56 of 63 patients), 75% (9 of 12 patients), and 100% (47 of 47 patients) in the final decisions, respectively. CT showed all associated pancreatobiliary diseases except bile duct stones in two patients. CONCLUSION: MDCT enabled the diagnosis of an anomalous pancreaticobiliary ductal junction by showing whether the pancreatic and biliary ducts join within the pancreatic parenchyma on high-resolution multiplanar reconstruction images.

Assessment of the main pancreatic duct using computed tomography with multiplanar reconstructions.

UNLABELLED: The aim of this study was to assess the morphology of the main pancreatic duct (MPD) using multiplanar reconstructions and to compare this with the morphology of the MPD of anatomic subjects. MATERIALS AND METHODS: The morphology of the MPD was studied by means of multiplanar reconstructions obtained on the one hand from thin tomodensitometric slices and on the other hand from the dissection of anatomic subjects. This study involved 15 subjects in each group. RESULTS: Full multiplanar reconstruction was obtained in 13 cases. In 2 cases, the isthmus did not appear in the reconstructions. The morphology of the MPD was similar in both groups. The length of the MPD was identical at the head and isthmus of the pancreas in both groups but was greater in the dissection group than in the reconstruction group in the body and tail areas of the pancreas. The diameter of the MPD was greater at the head of the pancreas in the dissection group and was identical in both groups for the other segments of the MPD. CONCLUSIONS: Multiplanar tomodensitometric reconstruction of the main pancreatic duct is feasible. This new technique, currently under evaluation, could allow the study of canalar pathologies of the pancreas through tomodensitometry.

Preoperative assessment of pancreatic malignancy using endoscopic ultrasound.

BACKGROUND: Endoscopic ultrasound (EUS) has been regarded as the most accurate modality for locoregional staging of pancreatic malignancy. However, several recent studies have questioned this. The current study assessed the accuracy of EUS in determining preoperative resectability of pancreatic neoplasia. METHODS: A retrospective review was performed of patients with pancreatic malignancy who had preoperative EUS and underwent surgery. EUS-predicted resectability was compared with surgical resectability. Where available, accuracies of vascular and nodal staging were also assessed. RESULTS: Forty-five patients were identified (mean age 60 years, age range = 36-79 years). All patients underwent surgical exploration; vascular staging was available in 32 cases and 17 cases underwent surgical resection. The sensitivity, specificity, and accuracy of EUS in determining unresectability were 66%, 100%, and 78% respectively. Overall EUS stage concurred with surgical stage in 56%, greater than surgical stage in 4%, and less than surgical stage in 40%. Vascular staging on EUS had a sensitivity of 69% and a specificity of 100%. Accuracy of nodal staging was 71%. CONCLUSION: EUS had a high specificity for assessing unresectable pancreatic malignancy. This technique should be used to avoid unnecessary surgical exploration of incurable lesions. However, EUS had only a moderate sensitivity, and a proportion of patients staged preoperatively as having resectable disease will not be surgically resectable.

Assessment of the pancreatic and intrapancreatic bile ducts using 0.5-mm collimation and multiplanar reformatted images in multislice CT.

Our objective was to evaluate the ability of multiplanar reformatted (MPR) images combined with 0.5-mm axial images to depict the pancreatic and intrapancreatic bile ducts and compare the results with those of 0.5-mm axial, 2-mm axial, and 6-mm axial images alone. Seventy-seven patients without obstruction of the main pancreatic ducts (MPD) underwent dual-phase helical scanning of the pancreas using multislice computed tomography (MSCT). The MPR images were generated from 0.5-mm-thick images. Visualization of the pancreatic and intrapancreatic bile ducts and their confluence was graded on a four-point scale by a consensus of two radiologists. The results for 0.5-mm axial images in early-phase CT, 2-mm axial images in early-phase CT, MPR images combined with 0.5-mm axial images in early-phase CT, and 6-mm axial images in late-phase CT were then compared. The relationships of the focal pancreatic lesions with the pancreatic ducts were analyzed. The MPR images combined with 0.5-mm axial images were significantly superior to the other three types of images for the visualization of the pancreatic and intrapancreatic bile ducts and their confluence (p<0.01). The depiction rate of the MPD using MPR images combined with 0.5-mm axial images was 94, 94, 95, and 75%, respectively in the head, neck, body, and tail of the pancreas. Accessory pancreatic ducts, intrapancreatic bile ducts, and duct confluence were depicted in 48, 99, and 92%, respectively. In comparison with evaluation based on axial images alone, the use of MPR images more clearly demonstrated the relationship between the lesions and the pancreatic ducts in 14 of 19 lesions. The MPR images combined with 0.5-mm axial images improve the CT depiction of the pancreatic and intrapancreatic bile ducts in comparison with 0.5-mm axial, 2-mm axial, and 6-mm axial images alone.

The assessment of pancreatic exocrine function by bentiromide test in patients with chronic portal vein thrombosis.

INTRODUCTION: It has been noted in the literature that cavernous transformation of the portal vein (CTPV) can cause pancreatic duct atrophy, probably by enhanced collateral formation, but the clinical significance of this has not been established. AIMS: To evaluate whether CTPV affects the pancreatic exocrine functions. METHODOLOGY: Eighteen patients with CTPV were identified and prospectively studied. In these cases, despite a full clinical, biochemical, radiologic, and hematological evaluation, we found no etiologic factor for thrombosis in the portal vein (PV). All patients underwent a detailed evaluation for pancreatic morphology and pancreatic exocrine functions. In all cases, abdominal Doppler ultrasonography (US), abdominal spiral computed tomography (CT), and endoscopic retrograde cholangiopancreatography (ERCP) were performed for evaluation of pancreatic morphology. For the purpose of this study, serial biochemical tests, including measurement of serum amylase, pancreatic amylase, lipase, glucose, calcium, and lipids, were performed every 3 months. All 18 patients also underwent a bentiromide test to determine whether there was any exocrine pancreatic insufficiency. The findings were compared with those for 20 healthy control subjects and reference controls. RESULTS: For all 18 patients with idiopathic CTPV and all controls, ERCP was performed successfully. The pancreatic duct was determined to be smaller than in control subjects and in a reference control group ( < 0.05). In this group serum pancreatic amylase, alkaline phosphatase, and direct bilirubin levels were found to be higher than in controls, and statistically important differences between the two groups ( < 0.05) were documented. In all 18 subjects the bentiromide test was well tolerated and was performed successfully. For 15 of them (83%), we found that urinary excretion of para-amino benzoic acid (PABA) was significantly less than in control subjects and the reference control group ( < 0.05). CONCLUSION: Pancreatic duct atrophy in patients with CTPV is clinically significant. When clinical signs are not manifest and routine biochemical tests are not useful for detecting exocrine pancreatic insufficiency, the bentiromide test is highly sensitive and specific for detecting probable pancreatic insufficiency in patients with CTPV.

Magnetic resonance cholangiopancreatography: non-invasive imaging for the biliary tree and pancreatic duct.

Producing images similar to those acquired by the invasive procedures of endoscopic retrograde cholangiopancreatography (ERCP) or percutaneous transhepatic cholangiography, magnetic resonance cholangiopancreatography (MRCP) is indicated in patients who are unable to undergo ERCP or have had previously unsuccessful ERCP. It is used increasingly in non-invasive evaluation of the pancreaticobiliary tree in cases where the need for intervention during ERCP is expected to be low. MRCP may help in identifying anomalous biliary anatomy or choledocholithiasis before laparoscopic cholecystectomy, and in deciding between percutaneous or endoscopic treatment for patients with obstructive jaundice to decrease the rate of failed ERCP procedures.