Multimodality imaging of pancreatic and biliary congenital anomalies

Incidentally detected pancreatic duct dilatation on ultrasound and role of MRI

OBJECTIVE

The clinical significance of incidentally detected pancreatic duct (PD) dilatation at ultrasound (US) without a visualized underlying cause is unclear. We aimed to assess the role of subsequent MRI (including MRCP) and to identify US imaging and laboratory findings predictive of underlying pancreaticobiliary malignancy at the time of initial US.

MATERIALS AND METHODS

Patients with incidentally detected PD dilatation at ultrasound from 2011 to 2019 that had an ensuing MRI were included. Based on MRI results patients were divided into three groups: malignant pancreaticobiliary causes, benign causes and idiopathic PD dilatation. Subsequently the diagnostic ability of MRI was assessed. Initial ultrasound findings and laboratory results were compared between groups to identify predictors of underlying pancreaticobiliary pathology. A p-value < .05 was considered statistically significant.

RESULTS

In 37/59 (63%) patients PD dilatation was confirmed on MRI. MRI demonstrated malignant 7/59 (12%) and benign 10/59 (17%) causes of PD dilatation detected at initial ultrasound. Sensitivity, specificity, negative predictive value, positive predictive value and accuracy of MRI to ascertain the cause of PD dilatation was 89%, 100%, 95%, 100% and 97% respectively. Patients with a larger magnitude of PD dilatation, concomitant CBD dilatation and elevated lipase values were more likely to have underlying pancreaticobiliary malignancy (p < 0.05). No patient with initial negative MRI had pancreaticobiliary malignancy on subsequent work-up.

CONCLUSION

Incidentally detected PD dilatation on ultrasound is an important finding and should prompt referral to MRI. MRI is an accurate, noninvasive method for identifying the underlying cause of PD dilatation in these patients and in excluding pancreaticobiliary malignancy.

Study of non-alcoholic fatty pancreatic disease among the Egyptian population and the value of serum fatty acid binding protein-1 (FABP-1) as a non-invasive biomarker

BACKGROUND

Non-alcoholic fatty pancreas disease (NAFPD) can be detected using various imaging techniques, but accurately measuring the amount of fat in the pancreas remains difficult. Fatty acid binding protein-1 (FABP-1) is a marker specific to certain tissues and can aid in diagnosing NAFPD. However, this study aimed to investigate the prevalence of NAFPD among obese and non-obese people with and without diabetes mellitus (DM). Additionally, it aimed to evaluate the associated risk factors for NAFPD and the utility of the FABP-1 level as a simple, non-invasive biomarker for diagnosing NAFPD.

METHODS

This study is a prospective cross-sectional study.

RESULTS

Ninety-five patients were enrolled in the study, comprising 35 males and 60 females, with a mean age of 44 years and a standard deviation (SD) of 11 years. However, 26.3 % were morbidly obese, 22.1 % were severely obese, 31.6 % were obese, 12.6 % were overweight, and 7.4 % were normal. Additionally, 35.8 % had diabetes mellitus, while 26.3 % of patients had hypertension. Regarding the ultrasonographic findings, 94.7 % of the patients had fatty liver, with the majority (41.1 %) classified as grade II, followed by 38.9 % classified as grade I, and 14.7 % classified as grade III fatty liver. Among these patients, 78.9 % had fatty pancreas, with 38.9 % classified as grade II, 31.6 % classified as grade I, and 8.4 % classified as grade III fatty pancreas. The median FABP-1 level among patients with fatty pancreas was 3.3 ng/ml, which exhibited a significant fair negative correlation with total bilirubin and a fair, positive correlation with alkaline phosphatase and portal vein diameter. A statistically substantial distinction was observed between the levels of AFABP-1 and the presence or grading of the fatty pancreas (p-value = 0.048 and < 0.001, respectively). Using multivariate analysis, FABP-1 was the only significant predictor of a fatty pancreas. The receiver operating characteristic (ROC) curve analysis indicated that at a cut-off point of FABP-1 of ≤ 3.7, it had a sensitivity of 58 %, specificity of 80 %, positive predictive value (PPV) of 96.6 %, negative predictive value (NPV) of 17 %, and an area under the curve (AUC) of 0.77.

CONCLUSION

NAFPD is becoming an increasingly significant challenge. FABP-1 can potentially be a straightforward and non-invasive predictor of the fatty pancreas.

Pancreatic Iodine Density and Fat Fraction on Dual-Energy Computed Tomography in Acute Pancreatitis

The aim of our study was to investigate iodine density (ID) and fat fraction (FF) on dual-energy computed tomography (DECT) in patients with acute pancreatitis (AP). This retrospective study included 72 patients with clinically confirmed AP and 62 control subjects with DECT of the abdomen. Two radiologists assessed necrosis and measured attenuation values, ID, and FF in three pancreatic segments. We used receiver operating characteristic (ROC) analysis to determine the optimal threshold for ID for the differentiation between AP groups. The ID was significantly higher in interstitial edematous AP compared to necrotizing AP and the control group (both p < 0.05). The ROC curve analysis revealed the thresholds of ID for detecting pancreatic necrosis ≤ 2.2, ≤2.3, and ≤2.4 mg/mL (AUC between 0.880 and 0.893, p > 0.05) for the head, body, and tail, respectively. The FF was significantly higher for pancreatitis groups when compared with the control group in the head and body segments (both p < 0.001). In the tail, the difference was significant in necrotizing AP (p = 0.028). The ID values were independent of attenuation values correlated with the FF values in pancreatic tissue. Iodine density values allow for differentiation between morphologic types of AP.

Early features of pancreatic cancer on magnetic resonance imaging (MRI): a case-control study

PURPOSE

Magnetic resonance imaging has been recommended as a primary imaging modality among high-risk individuals undergoing screening for pancreatic cancer. We aimed to delineate potential precursor lesions for pancreatic cancer on MR imaging.

METHODS

We conducted a case-control study at Kaiser Permanente Southern California (2008-2018) among patients that developed pancreatic cancer who had pre-diagnostic MRI examinations obtained 2-36 months prior to cancer diagnosis (cases) matched 1:2 by age, gender, race/ethnicity, contrast status and year of scan (controls). Patients with history of acute/chronic pancreatitis or prior pancreatic surgery were excluded. Images underwent blind review with assessment of a priori defined series of parenchymal and ductal features. We performed logistic regression to assess the associations between individual factors and pancreatic cancer. We further assessed the interaction among features as well as performed a sensitivity analysis stratifying based on specific time-windows (2-3 months, 4-12 months, 13-36 months prior to cancer diagnosis).

RESULTS

We identified 141 cases (37.9% stage I-II, 2.1% III, 31.4% IV, 28.6% unknown) and 292 matched controls. A solid mass was noted in 24 (17%) of the pre-diagnostic MRI scans. Compared to controls, pre-diagnostic images from cancer cases more frequently exhibited the following ductal findings: main duct dilatation (51.4% vs 14.3%, OR [95% CI]: 7.75 [4.19-15.44], focal pancreatic duct stricture with distal (upstream) dilatation (43.6% vs 5.6%, OR 12.71 [6.02-30.89], irregularity (42.1% vs 6.0%, OR 9.73 [4.91-21.43]), focal pancreatic side branch dilation (13.6% vs1.6%, OR 11.57 [3.38-61.32]) as well as parenchymal features: atrophy (57.9% vs 27.4%, OR 46.4 [2.71-8.28], focal area of signal abnormality (39.3% vs 4.8%, OR 15.69 [6.72-44,78]), all p < 0.001).

CONCLUSION

In addition to potential missed lesions, we have identified a series of ductal and parenchymal features on MRI that are associated with increased odds of developing pancreatic cancer.

Pancreatic congenital anomalies and their features on CT and MR imaging: a pictorial review

OBJECTIVE

To review the congenital anomalies of the pancreas with their main clinical manifestations and key imaging findings on CT and MRI.

BACKGROUND AND CLINICAL SIGNIFICANCE

Anomalies of pancreatic development are frequent and generally asymptomatic, but can mimic and predispose individuals to pancreatic or peripancreatic pathologies, such as pancreatitis or malignancy. Their correct diagnosis may help avoid unnecessary further investigations and procedures, or establish adequate treatment when they manifest clinically. Differentiating pancreatic congenital anomalies from their main radiological mimics constitutes a challenge for the radiologist and requires familiarity with key imaging findings.

CONCLUSION

The imaging findings of CT and MRI are essential for the correct diagnosis of congenital pancreatic anomalies.

A Rare Case of Wirsung Duct Duplication with Chronic Pancreatitis

Teaching point: Wirsung duct duplication is a very rare condition that can lead to chronic pancreatitis.

Biliary Disorders, Anomalies, and Malignancies in Children

Biliary abnormalities in children are uncommon, and the spectrum of biliary disorders is broader than in adult patients. Unlike in adults, biliary disorders in children are rarely neoplastic and are more commonly rhabdomyosarcoma rather than cholangiocarcinoma. Pediatric biliary disorders may be embryologic or congenital, such as anatomic gallbladder anomalies, anomalous pancreaticobiliary tracts, various cholestatic processes, congenital cystic lesions, or genetic conditions. They may also be benign, such as biliary filling anomalies, biliary motility disorders, and biliary inflammatory and infectious disorders. Distinguishing these entities with a single imaging modality is challenging. US is the primary imaging modality for initial evaluation of biliary abnormalities in children, due to its wide availability, lack of ionizing radiation, and low cost and because it requires no sedation. Other examinations such as MRI, CT, and nuclear medicine examinations may provide anatomic and functional information to narrow the diagnosis further. Hepatobiliary-specific contrast material with MRI can provide better assessment of biliary anatomy on delayed images than can traditional MRI contrast material. MR cholangiopancreatography (MRCP) allows visualization of the intra- and extrahepatic biliary ducts, which may not be possible with endoscopic retrograde cholangiopancreatography (ERCP). Suspected biliary atresia requires multiple modalities for diagnosis and timely treatment. Determining the type of choledochal cyst calls for a combination of initial US and MRCP. Many benign and malignant biliary masses require biopsy for definitive diagnosis. Knowledge of the imaging appearances of different pediatric biliary abnormalities is necessary for appropriate imaging workup, providing a diagnosis or differential diagnosis, and guiding appropriate management. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Risk Assessment and Radiomics Analysis in Magnetic Resonance Imaging of Pancreatic Intraductal Papillary Mucinous Neoplasms (IPMN)

Intraductal papillary mucinous neoplasms (IPMNs) are a very common incidental finding during patient radiological assessment. These lesions may progress from low-grade dysplasia (LGD) to high-grade dysplasia (HGD) and even pancreatic cancer. The IPMN progression risk grows with time, so discontinuation of surveillance is not recommended. It is very important to identify imaging features that suggest LGD of IPMNs, and thus, distinguish lesions that only require careful surveillance from those that need surgical resection. It is important to know the management guidelines and especially the indications for surgery, to be able to point out in the report the findings that suggest malignant degeneration. The imaging tools employed for diagnosis and risk assessment are Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) with contrast medium. According to the latest European guidelines, MRI is the method of choice for the diagnosis and follow-up of patients with IPMN since this tool has a highest sensitivity in detecting mural nodules and intra-cystic septa. It plays a key role in the diagnosis of worrisome features and high-risk stigmata, which are associated with IPMNs malignant degeneration. Nowadays, the main limit of diagnostic tools is the ability to identify the precursor of pancreatic cancer. In this context, increasing attention is being given to artificial intelligence (AI) and radiomics analysis. However, these tools remain in an exploratory phase, considering the limitations of currently published studies. Key limits include noncompliance with AI best practices, radiomics workflow standardization, and clear reporting of study methodology, including segmentation and data balancing. In the radiological report it is useful to note the type of IPMN so as the morphological features, size, rate growth, wall, septa and mural nodules, on which the indications for surveillance and surgery are based. These features should be reported so as the surveillance time should be suggested according to guidelines.

Pancreatic duct pressure: A review of technical aspects and clinical significance

Pancreatic duct pressure (PDP) dynamics comprise an intricately modulated system that helps maintain homeostasis of pancreatic function. It is affected by various factors, including the rate of pancreatic fluid secretion, patency of the ductal system, sphincter of Oddi function, and pancreatic fluid characteristics. Disease states such as acute and chronic pancreatitis can alter the normal PDP dynamics. Ductal hypertension or increased PDP is suspected to be involved in the pathogenesis of pancreatic pain, endocrine and exocrine pancreatic insufficiency, and recurrent pancreatitis. This review provides a comprehensive appraisal of the available literature on PDP, including the methods used in the measurement and clinical implications of elevated PDP.

A CT-based nomogram established for differentiating gastrointestinal heterotopic pancreas from gastrointestinal stromal tumor: compared with a machine-learning model

OBJECTIVE

To identify CT features and establish a nomogram, compared with a machine learning-based model for distinguishing gastrointestinal heterotopic pancreas (HP) from gastrointestinal stromal tumor (GIST).

MATERIALS AND METHODS

This retrospective study included 148 patients with pathologically confirmed HP (n = 48) and GIST (n = 100) in the stomach or small intestine that were less than 3 cm in size. Clinical information and CT characteristics were collected. A nomogram on account of lasso regression and multivariate logistic regression, and a RandomForest (RF) model based on significant variables in univariate analyses were established. Receiver operating characteristic (ROC) curve, mean area under the curve (AUC), calibration curve and decision curve analysis (DCA) were carried out to evaluate and compare the diagnostic ability of models.

RESULTS

The nomogram identified five CT features as independent predictors of HP diagnosis: age, location, LD/SD ratio, duct-like structure, and HU lesion/pancreas A. Five features were included in RF model and ranked according to their relevance to the differential diagnosis: LD/SD ratio, HU lesion/pancreas A, location, peritumoral hypodensity line and age. The nomogram and RF model yielded AUC of 0.951 (95% CI: 0.842-0.993) and 0.894 (95% CI: 0.766-0.966), respectively. The DeLong test found no statistically significant difference in diagnostic performance (p > 0.05), but DCA revealed that the nomogram surpassed the RF model in clinical usefulness.

CONCLUSION

Two diagnostic prediction models based on a nomogram as well as RF method were reliable and easy-to-use for distinguishing between HP and GIST, which might also assist treatment planning.

Association between anatomic variations of extrahepatic and intrahepatic bile ducts: Do look up!

Biliary anatomic variations are usually asymptomatic, but they may cause problems in diagnostic investigations and interventional and surgical procedures, increasing both their technical difficulty and their postoperative complication rates. The aim of the present study was to evaluate the prevalence of anatomic variations in the intrahepatic biliary ducts (IHBD) in relation to demographical and clinical characteristics in a large study population requiring magnetic resonance cholangiopancreatography (MRCP) for various clinical conditions. The possible association between IHBD and extrahepatic biliary ducts (EHBD) variants was then explored. From January 2017 to May 2019, 1004 patients underwent MRCP. Demographical and clinical data were collected. IHBD and EHBD anatomy were recorded and the EHBD anatomy was classified using both qualitative and quantitative classifications. The presence of a type 3 EHBD variant (an abnormal proximal cystic duct [CD] insertion) in both qualitative and quantitative classifications and an intrapancreatic CD were associated with the presence of IHBD variants at univariate analysis (p = 0.008, p = 0.019, and p = 0.001, respectively). The presence of a posterior or medial insertion of the CD into the EHBD was a strong predictive factor of the presence of IHBD variants both at uni- and multivariate analysis (p = 0.002 and p = 0.003 for posterior insertion and p = 0.002 and p = 0.002 for medial insertion, respectively). The presence of gallstones on MRCP resulted in a strong predictor of the presence of an anatomical variant of the IHBD both at uni- and multivariate analysis (p = 0.027 and p = 0.046, respectively). In conclusion, the presence of a type 3 variant of the EHBD, an intrapancreatic CD and, especially, a posterior/medial CD insertion into the EHBD represent predictive factors of the concomitant presence of IHBD variants, thus radiologists must be vigilant when encountering these EHBD configurations and always remember to "look up" at the IHBD. Finally, the presence of an IHBD variant is a strong predictive factor of gallstones.

Risk Factors Associated with Acute Pancreatitis after Percutaneous Biliary Intervention: We Do Not Know Nearly Enough

Percutaneous transhepatic cholangiodrainage (PTCD) and percutaneous transhepatic biliary stenting (PTBS) may be used as a palliative treatment for inoperable patients with malignant biliary obstruction (MBO) to improve the prognosis and their quality of life. However, acute pancreatitis is a common and severe complication that cannot be ignored after PTCD and PTBS in patients with MBO. A few cases may develop severe pancreatitis with a higher mortality rate. In this study, we summarize the known risk factors for acute pancreatitis after percutaneous biliary interventional procedures and investigate possible risk factors to reduce its occurrence by early identifying high-risk patients and taking appropriate measures.

Standardization of MRI Screening and Reporting in Individuals With Elevated Risk of Pancreatic Ductal Adenocarcinoma: Consensus Statement of the PRECEDE Consortium

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies, with a dismal survival rate. Screening the general population for early detection of PDAC is not recommended, but because early detection improves survival, high-risk individuals, defined as those meeting criteria based on a family history of PDAC and/or the presence of known pathogenic germline variant genes with PDAC risk, are recommended to undergo screening with MRI and/or endoscopic ultrasound at regular intervals. The Pancreatic Cancer Early Detection (PRECEDE) Consortium was formed in 2018 and is composed of gastroenterologists, geneticists, pancreatic surgeons, radiologists, statisticians, and researchers from 40 sites in North America, Europe, and Asia. The overarching goal of the PRECEDE Consortium is to facilitate earlier diagnosis of PDAC for high-risk individuals to increase survival of the disease. A standardized MRI protocol and reporting template are needed to enhance the quality of screening examinations, improve consistency of clinical management, and facilitate multiinstitutional research. We present a consensus statement to standardize MRI screening and reporting for individuals with elevated risk of pancreatic cancer.

Pancreas bifidum: an extremely rare cause of acute pancreatitis

A wide spectrum of anomalies of the pancreas, the pancreatic ductal system and the biliary tree are commonly encountered at radiologic evaluation. Pancreas bifidum, also known as bifid pancreas or fish-tail pancreas, is an extremely rare congenital branching anomaly of the main pancreatic duct characterized by its duplication. These 2 separate ducts are laid from the pancreatic tail to neck and they generally join at the pancreas body-tail draining via the major papilla; the pancreatic parenchyma is also bifurcated with separated dorsal and caudal buds. The clinical impact of this condition is not well established: although some authors sustained that probably does not cause or contribute to abdominal pain or overt pancreatic diseases, others argued that could be considered as a possible cause of acute pancreatitis.

We herewith describe the case of a 51-year-old woman presenting to our hospital with epigastric pain, nausea, and vomiting. Biochemical tests were suspicious for acute pancreatitis. Ultrasound examination was negative. MRI, including MR cholangiopancreatography revealed bifid pancreas characterized by duplication of the main pancreatic duct with 2 separate ducts that join at the pancreas head and draining via the minor papilla. On T2-weighted images the ventral bud of the pancreas was enlarged and characterized by slightly hyperintensity without peripancreatic fluid collections. The MRI findings were consistent with acute pancreatitis limited to the ventral bud of a bifid pancreas. Patient was treated with intravenous fluid resuscitation, pain control and institution of early enteral nutrition and discharged on the seventh day after admission.

Anatomical pancreatic variants in intraductal papillary mucinous neoplasm patients: a cross-sectional study

Background

No previous studies have examined the possible relationship between intraductal papillary mucinous neoplasm (IPMN) and the developmental ductal variations of the pancreas, such as an ansa pancreatica and a meandering main pancreatic duct (MMPD).

Methods

This retrospective cross-sectional study enrolled 214 patients, 108 with IPMN disease and 106 subjects from a community at the tertiary care unit. The main pancreatic duct (MPD) was evaluated in the head of the pancreas by its course, which were non-MMPD: descending, vertical, and sigmoid, or MMPD including loop types, reverse-Z subtypes, and an N-shape, which was identified for the first time in this study. IPMN patients were also evaluated for worrisome features (WF) or high-risk stigmata (HRS), and the extent of IPMN cysts.

Results

Among IPMN patients, 18.4% had MMPD, which we observed in only 3.0% of the control group (P < 0.001). Patients with MMPD were more likely to belong to the IPMN group compared with non-MMPD patients [odds ratio (OR) 6.4, 95% confidence interval (CI) 2.2–24.9]. Compared with a descending shape MPD, IPMN patients with an N-shaped MPD were more likely to have a cystic mural nodule (OR 5.9, 95% CI 1.02–36.0). The presence of ansa pancreatica associated with more extent IPMN disease (OR 12.8, 95% CI 2.6–127.7).

Conclusions

IPMN patients exhibited an MMPD more often than control patients. Ansa pancreatica associated with multiple cysts. Furthermore, an N-shape in IPMN patients associated with cystic mural nodules, suggesting that this shape serves as a risk factor for more severe IPMN.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02465-w.

Study of Learning Curve in a Surgeon for Near-Infrared Fluorescence Cholangiography During Laparoscopic Cholecystectomy-A Retrospective Evaluation

BACKGROUND

Near-infrared indocyanine green fluorescence cholangiography (NIRF) has shown promising results on delineating extra-hepatic biliary anatomy during laparoscopic cholecystectomy to avoid bile duct injury. However its routine usage remains in question. In this study, the technique was evaluated further with learning curve estimation and learning factors were observed.

METHODS

One hundred ninety-nine cases which underwent laparoscopic cholecystectomy for acute or chronic cholecystitis within a 2-year period including 51 cases with initial use of NIRF by 2 surgeons were studied retrospectively. The learning curve was evaluated for a surgeon as primary objective. A case-matched comparison of the operative time between NIRF and conventional group, in terms of acute and chronic cholecystitis was also conducted as a secondary calculation.

RESULTS

Learning curve was evaluated with 61% learning rate for NIRF experience. Cysto-biliary junction non-illuminated cases under fluorescent view, had mean operative time of 80.83 ± 22.82 min, which was shorter than the cysto-biliary junction illuminated cases. The NIRF group exhibited longer operative time compared with the conventional group with mean difference of 34.39 min (significant at P < .05).

CONCLUSIONS

While the initial learning phase might be affected by surgeons' behavior and attitude, our results may provide a reference to learn at one's own pace and to employ NIRF teaching strategies during surgical training programs to overcome the initial phase during training period itself and facilitate universal achievement.

Fatty Pancreas-Centered Metabolic Basis of Pancreatic Adenocarcinoma: From Obesity, Diabetes and Pancreatitis to Oncogenesis

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest types of cancer, and it is currently the third most common cause of cancer death in the U.S.A. Progress in the fight against PDAC has been hampered by an inability to detect it early in the overwhelming majority of patients, and also by the reduced oxygen levels and nutrient perfusion caused by new matrix formation through the activation of stromal cells in the context of desmoplasia. One harbinger of PDAC is excess intrapancreatic fat deposition, namely, fatty pancreas, which specifically affects the tumor macro- and microenvironment in the organ. Over half of PDAC patients have diabetes mellitus (DM) at the time of diagnosis, and fatty pancreas is associated with subsequent DM development. Moreover, there is a strong association between fatty pancreas and fatty liver through obesity, and a higher intrapancreatic fat percentage has been noted in acute pancreatitis patients with DM than in those without DM. All these findings suggest that the link between fatty pancreas and PDAC might occur through metabolic alterations, either DM-related or non-DM-related. Based on clinical, in vivo and in vitro evidence, the current review highlights the etiologies of fatty pancreas (including fatty infiltration and replacement) and the fatty pancreas-associated metabolic alterations involved in oncogenesis to provide crucial targets to prevent, detect, and/or effectively treat PDAC.

Single-operator peroral pancreatoscopy in the preoperative diagnostics of suspected main duct intraductal papillary mucinous neoplasms: efficacy and novel insights on complications

Background

Distinguishing intraductal papillary mucinous neoplasms (IPMNs) from other pancreatic cystic lesions is essential since IPMNs carry the risk of becoming malignant. Differentiating the main pancreatic duct involving IPMNs (MD-IPMNs) through conventional imaging is deficient. Single-operator peroral pancreatoscopy (SOPP) represents a promising method offering additional information on suspected lesions in the pancreatic main duct (MD). We aimed to determine the role of SOPP in the preoperative diagnostics of suspected MD-IPMNs and identify factors contributing to SOPP-related complications.

Materials and Methods

In this primarily retrospective study, SOPPs were performed at three high-volume centers on suspected MD-IPMNs. Primary outcome was the clinical impact of SOPP to subsequent patient care. Additionally, we documented post-SOPP complications and analyzed several assumed patient- and procedure-related risk factors.

Results

One hundred and one (101) SOPPs were performed. Subsequent clinical management was affected due to the findings in 86 (85%) cases. Surgery was planned for 29 (29%) patients. A condition other than IPMN explaining MD dilatation was found in 28 (28%) cases. In 35 (35%) cases, follow-up with MRI was continued. Post-SOPP pancreatitis occurred in 20 (20%) patients and one of them was fatal. A decrease in odds of post-SOPP pancreatitis was seen as the MD diameter increases (OR 0.714 for 1.0 mm increase in MD diameter, CI 95% 0.514–0.993, p = 0.045). Furthermore, a correlation between lower MD diameter values and higher severity post-SOPP pancreatitis was seen (T_JT = 599, SE = 116.6, z = − 2.31; p = 0.020). History of pancreatitis after endoscopic retrograde cholangiopancreatography was a confirmed risk factor for post-SOPP pancreatitis. Conclusions between complications and other risk factors could not be drawn.

Conclusion

SOPP aids clinical decision-making in suspected MD-IPMNs. Risk for post-SOPP pancreatitis is not negligible compared to non-invasive imaging methods. The risk for pancreatitis decreases as the diameter of the MD increases.

Development of the human pancreas and its exocrine function

The pancreas has both endocrine and exocrine function and plays an important role in digestion and glucose control. Understanding the development of the pancreas, grossly and microscopically, and the genetic factors regulating it provides further insight into clinical problems that arise when these processes fail. Animal models of development are known to have inherent issues when understanding human development. Therefore, in this review, we focus on human studies that have reported gross and microscopic development including acinar-, ductal-, and endocrine cells and the neural network. We review the genes and transcription factors involved in organ formation using data from animal models to bridge current understanding where necessary. We describe the development of exocrine function in the fetus and postnatally. A deeper review of the genes involved in pancreatic formation allows us to describe the development of the different groups (proteases, lipids, and amylase) of enzymes during fetal life and postnatally and describe the genetic defects. We discuss the constellation of gross anatomical, as well as microscopic defects that with genetic mutations lead to pancreatic insufficiency and disease states.

Anatomic Variations of the Cystic Duct in Magnetic Resonance Cholangiopancreatography in Shiraz: A Cross-Sectional Study

BACKGROUND

Anatomic variations of the cystic duct (CD) are commonly encountered. Being aware of these variants will reduce complications subsequent to surgical, endoscopic, or percutaneous procedures. Magnetic resonance cholangiopancreatography (MRCP) is the least invasive and the most reliable modality for biliary anatomy surveys. This study aimed to determine the prevalence of cystic duct variations in the Iranian population.

METHODS

In this retrospective cross-sectional study, MRCP images of 350 patients referred to Shiraz Faraparto Medical Imaging and Interventional Radiology Center from October 2017 to October 2018 were reviewed. The CD course and insertion site to the extrahepatic bile duct (EHBD) was determined and documented in 290 cases. Descriptive statistics and Chi square test were applied for data analysis via SPSS software.

RESULTS

About 77% of cases revealed the classic right lateral insertion to the middle third of EHBD. The insertion of CD to the upper third and the right hepatic duct was 10%, and the insertion to the medial aspect of the middle third of EHBD from anterior or posterior was noted to be about 7.6%. From 2.8% of insertions to the lower third, 1% demonstrated parallel course, and finally, 0.3% of cases presented short CD.

CONCLUSION

CD variations are relatively common, and MRCP mapping prior to the hepatobiliary interventions could prevent unexpected consequences.

Insight into gastrointestinal heterotopic pancreas: imaging evaluation and differential diagnosis

Heterotopic pancreas (HP) is an uncommon congenital abnormality in the developmental process of the pancreas, with gastrointestinal heterotopic pancreas (GHP) being the most common HP. The clinical manifestations of GHP may have variable patterns of presentation, dictated by both the anatomic location and the functional ability of the lesion. The most common imaging modality in detecting GHP is computed tomography (CT), while gastrointestinal barium fluoroscopy, endoscopic ultrasonography, and magnetic resonance imaging (MRI) are also applied. The density and enhancement patterns of GHP are consistent with histological classifications. GHP with a predominantly acinar tissue component manifests homogeneous and marked enhancement on CT images, whereas a predominantly ductal GHP presents heterogeneous and mild enhancement. On MRI, the appearance and signal intensity of GHP were paralleled to the normal pancreas on all sequences and were characterized by T1-weighted high signal and early marked enhancement. This article provides a comprehensive review of the histopathology, clinical manifestations, imaging features of various modalities, and differential diagnosis of GHP. It is hoped that this review will improve clinicians' knowledge of GHP and aid in accurate preoperative diagnosis, thereby reducing the misdiagnosis rate.

Evaluation of the contour of the pancreas: types and frequencies

PURPOSE

Pancreas contour variations can sometimes be misdiagnosed as mass lesions. This study aimed to evaluate normal pancreatic contour morphology, variations, frequency and the development of the uncinate process.

METHODS

Out of 1183 consecutive computed tomography images taken in our hospital for various reasons (e.g. malignity, donor), 899 suitable images were included in the study. The following variations were identified: globular, elongated or globular-elongated contours of the pancreas head, protrusions of the body-tail surfaces and globular, lobular, globular-lobular, tapered and bifid contours of the tail. Hypoplasia and aplasia of the uncinate process were identified. All images were evaluated retrospectively by two radiologists.

RESULTS

Of the 899 patients, 504 (56.1%) were males. The mean age of the patients was 53.9 ± 14.7 (range 18-89). Hypoplasia of the uncinate process was found in 72 (8%) patients; aplasia was seen in 11 (1.2%) patients. Thirty-one (3.5%) of the pancreatic head variations were globular, 49 (5.4%) elongated and three (0.3%) elongated-globular. In patients with pancreatic uncinate process developmental anomaly, contour variations were also detected in the head of the pancreas. The pancreatic body-tail showed protrusions anteriorly in 76 (8%) patients and posteriorly in 11 (1.2%) patients. Seventy-two (8%) of the pancreatic tail variations were globular, 39 (4.4%) were globular-lobular, 18 (2%) were tapered and 17 (1.8%) were bifid.

CONCLUSION

Patients with pancreatic uncinate process developmental anomaly also have contour variations in the head of the pancreas. Pancreatic uncinate process developmental anomaly was seen in 9.2%. Pancreatic tail contour variation was 16.2%. The pancreatic body-tail showed protrusion in 9.2% of patients.

Recommendations for the Management of Incidental Pancreatic Findings in Adults by the Canadian Association of Radiologists Incidental Findings Working Group

The Canadian Association of Radiologists Incidental Findings Working Group consists of both academic subspecialty and general radiologists and is tasked with adapting and expanding upon the American College of Radiology incidental findings white papers to more closely apply to Canadian practice patterns, particularly more comprehensively dealing with the role of ultrasound and pursuing more cost-effective approaches to the workup of incidental findings without compromising patient care. Presented here are the 2021 Canadian guidelines for the management of pancreatic incidental findings. Topics covered include anatomic variants, fatty atrophy, pancreatic calcifications, ductal ectasia, and management of incidental pancreatic cysts.

Incidental Pancreatic Cysts on Cross-Sectional Imaging

Incidental pancreatic cysts are commonly encountered in radiology practice. Although some of these are benign, mucinous varieties have a potential to undergo malignant transformation. Characterization of some incidental pancreatic cysts based on imaging alone is limited, and given that some pancreatic cysts have a malignant potential, various societies have created guidelines for the management and follow-up of incidental pancreatic cysts. This article reviews the imaging findings and work-up of pancreatic cysts and gives an overview of the societal guidelines for the management and follow-up of incidental pancreatic cysts.

[Pancreas divisum and pancreatitis]

CLINICAL/METHODOLOGICAL ISSUE

Diagnostic and clinical relevance of pancreas divisum.

STANDARD RADIOLOGICAL METHODS

Ultrasonography (US), magnetic resonance cholangiopancreatography (MRCP), magnetic resonance imaging (MRI), computed tomography (CT), endoscopic retrograde cholangiopancreatography (ERCP).

PERFORMANCE

Pancreas divisum is an anatomic variation of pancreatic duct system with an incidence in general population of about 10%. It can become symptomatic in approximately 5% of patients. MRI with MRCP is the method of choice to diagnose pancreas divisum.

ACHIEVEMENTS

MRCP is equal to ERCP in diagnosing pancreas divisum in routine clinical practice as it is noninvasive, offers the possibility to evaluate the adjacent tissues and has almost no contraindications.

PRACTICAL RECOMMENDATIONS

It is important to be familiar with the anatomy of the pancreatic duct system in order to plan interventional procedures for symptomatic patients in due time.

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas: recommendations for Standardized Imaging and Reporting from the Society of Abdominal Radiology IPMN disease focused panel

There have been many publications detailing imaging features of malignant transformation of intraductal papillary mucinous neoplasms (IPMN), management and recommendations for imaging follow-up of diagnosed or presumed IPMN. However, there is no consensus on several practical aspects of imaging IPMN that could serve as a clinical guide for radiologists and enable future data mining for research. These aspects include how to measure IPMN, define reporting terminology, standardize reporting and unify guidelines for surveillance. The Society of Abdominal Radiology (SAR) created multiple Disease-Focused Panels (DFP) comprised multidisciplinary panel members who focus on a particular disease, with the goal to develop ways for radiologists to improve patient care, education, and research. DFP members met to identify the current controversies and limitations of imaging pancreatic IPMN. This paper aims to provide a practical review of the key imaging characteristics of IPMN for trainees and practicing radiologists, to guide uniformity of performance and interpretation of surveillance imaging studies, and to improve communication with clinicians by providing a lexicon and reporting template based on the experience of the SAR-DFP panel members.

Pediatric biliary disorders: Multimodality imaging evaluation with clinicopathologic correlation

The spectrum of pathologies affecting the biliary tree in the pediatric population varies depending on the age of presentation. While in utero insults can result in an array of anatomic variants and congenital anomalies in newborns, diverse acquired biliary pathologies are observed in older children. These acquired pathologies display different presentations and consequences than adults. Multimodality imaging assessment of the pediatric biliary system is requisite to establishing an appropriate management plan. Awareness of the imaging features of the various biliary pathologies and conveying clinically actionable information is essential to facilitate appropriate patient management. In this paper, we will illustrate the anatomy and embryology of the pediatric biliary system. Then, we will provide an overview of the imaging modalities used to assess the biliary system. Finally, we will review the unique features of the pediatric biliary pathologies, complemented by histopathologic correlation and discussions of clinical management.

Pancreatic Cancer-Associated Diabetes is Clinically Distinguishable From Conventional Diabetes

BACKGROUND

Type 3c diabetes mellitus (T3cDM) is diabetes secondary to other pancreatic diseases such as chronic pancreatitis, pancreatic resection, cystic fibrosis, and pancreatic ductal adenocarcinoma (PDA). Clinically, it may easily be confused with conventional type 2 diabetes mellitus (T2DM). A delay in pancreatic cancer diagnosis and treatment leads to a worse outcome. Therefore, early recognition of PDA-associated T3cDM and distinction from conventional T2DM represents an opportunity improve survival in patients with PDA.

METHODS

Six hundred and sixty four patients with PDA underwent pancreatic resection. Patients were classified as per whether or not they had diabetes. The specific type of diabetes was determined. T3cDM surgical patients (n = 127) were compared with a control group of medical patients with T2DM who did not have PDA (n = 127).

RESULTS

Patients with T3cDM were older (66 versus 61 y, P < 0.001), had lower body mass indices (25.9 versus 32.1, P < 0.001), more favorable hemoglobin A1c levels (7.0 versus 8.8, P < 0.001), higher alanine aminotransferase levels (39 versus 20, P < 0.001), and lower creatinine levels (0.8 versus 0.9 mg/dL, P < 0.001). In addition, they were more likely to be insulin dependent. In a subgroup analysis of surgical patients, T3cDM (versus surgical patients with T2DM and no diabetes) was not associated with surrogate markers of main pancreatic duct obstruction and glandular atrophy.

CONCLUSIONS

PDA-associated T3cDM has a distinctive presenting phenotype compared with medical patients with conventional T2DM. Greater attention to associated signs, symptoms, and biochemical data could identify patients at risk for harboring an underlying pancreatic malignancy and trigger diagnostic pathways leading to earlier PDA diagnosis and treatment.

Pictorial Summary of Congenital Gallbladder and Biliary Duct Anomalies Presentation on HIDA Imaging

Hepatobiliary iminodiacetic acid (HIDA) scan is one of the principal imaging modalities for the evaluation of the gallbladder and biliary tree. Congenital biliary anomalies are rare and can be difficult to recognize on HIDA scan. They may also mimic other biliary pathology. The purpose of this article is to review the spectrum of congenital gallbladder and biliary anomalies and describe their imaging appearance on HIDA scan. In addition, the diagnostic utility of functional imaging with HIDA when evaluating biliary tract anomalies is described.

North American Society for Pediatric Gastroenterology, Hepatology and Nutrition and the Society for Pediatric Radiology Joint Position Paper on Noninvasive Imaging of Pediatric Pancreatitis: Literature Summary and Recommendations

ABSTRACT

The reported incidence of pediatric pancreatitis is increasing. Noninvasive imaging, including ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI), play important roles in the diagnosis, staging, follow-up, and management of pancreatitis in children. In this position paper, generated by members of the Pancreas Committee of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) and the Abdominal Imaging Committee of The Society for Pediatric Radiology (SPR), we review the roles of noninvasive imaging in pediatric acute, acute recurrent, and chronic pancreatitis. We discuss available evidence related to noninvasive imaging, highlighting evidence specific to pediatric populations, and we make joint recommendations for use of noninvasive imaging. Further, we highlight the need for research to define the performance and role of noninvasive imaging in pediatric pancreatitis.

Use of computed tomography for distinguishing heterotopic pancreas from gastrointestinal stromal tumor and leiomyoma

PURPOSE

To determine whether morphologic features and semiquantitative parameters of computed tomography (CT) could be used to distinguish heterotopic pancreas from gastrointestinal stromal tumor (GIST) and leiomyoma.

METHODS

This retrospective study evaluated CT images of heterotopic pancreases (n = 28), GISTs (n = 57), and leiomyomas (n = 26) located in the upper gastrointestinal tract. Morphologic imaging features of lesions were analyzed, including location, contour, margin, attenuation, growth pattern, enhancement type, enhancement degree, enlarged vessels feeding or draining the mass, hyperenhancement of the overlying mucosa, low intralesional attenuation, calcification, and a duct-like structure. Semiquantitative parameters included long diameter (LD), short diameter (SD), LD/SD ratio, and lesion and aorta CT values during plain CT (Lp and Ap), arterial phase (La and Aa), and venous phase (Lv and Av). Diagnostic performance of these findings and parameters were evaluated by receiver operating characteristic (ROC) analysis.

RESULTS

Morphologic CT findings (including lesion contour, margin, attenuation, growth pattern, enhancement type, and enhancement degree) and semiquantitative parameters except for LD/SD were demonstrated to be significant for differentiating heterotopic pancreas from GIST and leiomyoma (all P < 0.01). Of these, location, low intralesional attenuation, duct-like structure and LD, SD, Lv, and Sv values showed good diagnostic performance with the areas under curve (AUC) higher than 0.70. The presence of a duct-like structure demonstrated the best diagnostic ability with AUC of 0.929 [95% confidence interval (CI) 0.864-0.969], sensitivity of 5.7% (95% CI 67.3-96.0), and specificity of 100% (95% CI 95.7-100), respectively. When the three morphologic features (location, low intralesional attenuation, duct-like structure) were used in combination, the AUC was improved to 0.980 (95% CI 0.952-1).

CONCLUSION

CT features, especially the morphologic features, could be used to differentiate heterotopic pancreas from GIST and leiomyoma in the upper gastrointestinal tract and, thus, provide a more accurate method for non-invasive preoperative diagnosis. Additionally, the presence of a duct-like structure demonstrated to be a reliable indicator for heterotopic pancreas among the morphologic and semiquantitative CT features.

A New Quantitative Classification of the Extrahepatic Biliary Tract Related to Cystic Duct Implantation

BACKGROUND

Knowledge regarding biliary anatomy and its variations, including the cystic duct (CD), is important in the pre-surgical setting and for predicting biliary diseases. However, no large series has focused on CD evaluation using a quantitative analysis. The primary aim of this prospective study was to create a 'taxonomic' classification of CD anatomy in a large cohort of subjects who underwent magnetic resonance cholangiopancreatography (MRCP). The secondary aim was to evaluate the correlations between extrahepatic bile duct (EHBD) variants and biliary diseases.

METHODS

We enrolled patients who underwent MRCP for different clinical indications from January 2017 to May 2019. Demographical, anatomical and clinical data were evaluated using statistical analyses, as appropriate. The anatomical assessment of EHBD was performed using the standard classification for CD in low, medium, and high insertions, and the lengths of CD to the duodenal papilla (DP), and EHBD was determined to conduct a new quantitative analysis.

RESULTS

The final study population comprised 1004 subjects. A new classification for EHBD as per the percentile distribution of the ratio CDDP/EHBD was designed, and the following categories were obtained: type 1 (below the 25th percentile) for CDDP/EHBD ratio ≤ 50%; type 2 (25th to 75th percentile) for CDDP/EHBD ratio 51-75% and type 3 (above the 75th percentiles) for CDDP/EHBD ratio > 75%. Type 1 of the new classification of CD implantation was significantly superior in terms of the detection of low, medial and intra-pancreatic CD that was significantly correlated with a high risk of choledochal lithiasis in comparison with the standard classification (P < 0.001).

CONCLUSIONS

The new classification of CD implantation enables identification of the vast majority of intra-pancreatic CDs that are correlated with a high risk of choledochal lithiasis in a single category (type 1) that is easy to identify using imaging.

Image-Based Machine Learning Algorithms for Disease Characterization in the Human Type 1 Diabetes Pancreas

Emerging data suggest that type 1 diabetes affects not only the β-cell-containing islets of Langerhans, but also the surrounding exocrine compartment. Using digital pathology, machine learning algorithms were applied to high-resolution, whole-slide images of human pancreata to determine whether the tissue composition in individuals with or at risk for type 1 diabetes differs from those without diabetes. Transplant-grade pancreata from organ donors were evaluated from 16 nondiabetic autoantibody-negative controls, 8 nondiabetic autoantibody-positive subjects with increased type 1 diabetes risk, and 19 persons with type 1 diabetes (0 to 12 years' duration). HALO image analysis algorithms were implemented to compare architecture of the main pancreatic duct as well as cell size, density, and area of acinar, endocrine, ductal, and other nonendocrine, nonexocrine tissues. Type 1 diabetes was found to affect exocrine area, acinar cell density, and size, whereas the type of difference correlated with the presence or absence of insulin-positive cells remaining in the pancreas. These changes were not observed before disease onset, as indicated by modeling cross-sectional data from pancreata of autoantibody-positive subjects and those diagnosed with type 1 diabetes. These data provide novel insights into anatomic differences in type 1 diabetes pancreata and demonstrate that machine learning can be adapted for the evaluation of disease processes from cross-sectional data sets.

Pancreatic Trauma: Imaging Review and Management Update

Traumatic injuries of the pancreas are uncommon and often difficult to diagnose owing to subtle imaging findings, confounding multiorgan injuries, and nonspecific clinical signs. Nonetheless, early diagnosis and treatment are critical, as delays increase morbidity and mortality. Imaging has a vital role in diagnosis and management. A high index of suspicion, as well as knowledge of the anatomy, mechanism of injury, injury grade, and role of available imaging modalities, is required for prompt accurate diagnosis. CT is the initial imaging modality of choice, although the severity of injury can be underestimated and assessment of the pancreatic duct is limited with this modality. The time from injury to definitive diagnosis and the treatment of potential pancreatic duct injury are the primary factors that determine outcome following pancreatic trauma. Disruption of the main pancreatic duct (MPD) is associated with higher rates of complications, such as abscess, fistula, and pseudoaneurysm, and is the primary cause of pancreatic injury-related mortality. Although CT findings can suggest pancreatic duct disruption according to the depth of parenchymal injury, MR cholangiopancreatography and endoscopic retrograde cholangiopancreatography facilitate direct assessment of the MPD. Management of traumatic pancreatic injury depends on multiple factors, including mechanism of injury, injury grade, presence (or absence) of vascular injury, hemodynamic status of the patient, and associated organ damage. ^©RSNA, 2020 See discussion on this article by Patlas.

Impacts on outcomes and management of preoperative magnetic resonance cholangiopancreatography in patients scheduled for laparoscopic cholecystectomy: for whom it should be considered?

Purpose

We evaluated the impact of preoperative magnetic resonance cholangiopancreatography (MRCP) on patient outcomes, and found which patients should be considered for MRCP before cholecystectomy.

Methods

We performed retrospective analysis of 2,072 patients that underwent cholecystectomy for benign gallbladder disease from January 2014 to June 2017. Patients were grouped as CT only group (n = 737) and MRCP group (n = 1,335), including both CT and MRCP (n = 1,292) or MRCP only (n = 43). The main outcome measure was associated with complications after cholecystectomy, and the secondary outcomes were hospital stay, readmission, and events that could impact patient management due to addition of MRCP.

Results

There were no statistical differences in occurrence of intraoperative or postoperative complications or readmission rate between the 2 groups. Hospital stay was about 0.6 days longer in the MRCP group. However, MRCP group was more susceptible to complications due to underlying patient demographics (older age, higher frequency of diabetes, and higher level of the inflammatory markers). MRCP diagnosed common bile duct (CBD) stones in 6.5% of patients (84/1,292) without CBD stones in CT, and bile duct anomalies were identified in 41 patients (3.2%). Elevated γ-GT was the only independent factor for additional detection of CBD stones (adjusted odds ratio [OR], 2.89; P = 0.029) and subsequent biliary procedures (adjusted OR, 3.34; P = 0.018) when additional MRCP was performed.

Conclusion

MRCP is valuable for identification of bile duct variation and CBD stones. Preoperative MRCP can be considered, particularly in patients with elevated γ-GT, for proper preoperative management and avoidance of complications.

Role of endoscopic ultrasonography in the diagnostic work-up of idiopathic acute pancreatitis (PICUS): study protocol for a nationwide prospective cohort study

INTRODUCTION

Idiopathic acute pancreatitis (IAP) remains a dilemma for physicians as it is uncertain whether patients with IAP may actually have an occult aetiology. It is unclear to what extent additional diagnostic modalities such as endoscopic ultrasonography (EUS) are warranted after a first episode of IAP in order to uncover this aetiology. Failure to timely determine treatable aetiologies delays appropriate treatment and might subsequently cause recurrence of acute pancreatitis. Therefore, the aim of the Pancreatitis of Idiopathic origin: Clinical added value of endoscopic UltraSonography (PICUS) Study is to determine the value of routine EUS in determining the aetiology of pancreatitis in patients with a first episode of IAP.

METHODS AND ANALYSIS

PICUS is designed as a multicentre prospective cohort study of 106 patients with a first episode of IAP after complete standard diagnostic work-up, in whom a diagnostic EUS will be performed. Standard diagnostic work-up will include a complete personal and family history, laboratory tests including serum alanine aminotransferase, calcium and triglyceride levels and imaging by transabdominal ultrasound, magnetic resonance imaging or magnetic resonance cholangiopancreaticography after clinical recovery from the acute pancreatitis episode. The primary outcome measure is detection of aetiology by EUS. Secondary outcome measures include pancreatitis recurrence rate, severity of recurrent pancreatitis, readmission, additional interventions, complications, length of hospital stay, quality of life, mortality and costs, during a follow-up period of 12 months.

ETHICS AND DISSEMINATION

PICUS is conducted according to the Declaration of Helsinki and Guideline for Good Clinical Practice. Five medical ethics review committees assessed PICUS (Medical Ethics Review Committee of Academic Medical Center, University Medical Center Utrecht, Radboud University Medical Center, Erasmus Medical Center and Maastricht University Medical Center). The results will be submitted for publication in an international peer-reviewed journal.

TRIAL REGISTRATION NUMBER

Netherlands Trial Registry (NL7066). Prospectively registered.

Pancreas divisum inversus

Pancreatic duct variations are usually diagnosed incidentally, in particular when using magnetic resonance cholangiopancreatography (MRCP), the most accurate imaging modality for depicting the pancreatic ductal system. However, the frequency and the embryologic development of pancreatic variants have not been well investigated. The purpose of this prospective study was to investigate the frequency of pancreatic ductal variants, providing potential explanations of their embryologic basis. The pancreatic ductal anatomies of 202 patients with mean ± standard deviation (SD) age of 54 ± 27 years, 56% females, who underwent MRCP for different indications between April 2018 and March 2019, were prospectively collected. Normal pancreatic ductal variants were identified in 196 cases (97%), and variants of pancreas divisum in six cases (3%). In the type C variant of the normal pancreatic anatomy, found in 3% of the cases, the dorsal duct was joined to the ventral duct while the accessory duct did not communicate with the dorsal duct. Unlike the classic type C variant, in our cases, the accessory pancreatic duct (APD) was long (mean ± SD of 58 ± 8.5 mm) and originated in the lower portion of the pancreatic head, caudally to the duct of Wirsung. This was a new subtype of the type C variant or a new variant, which could be called "pancreas divisum inversus"; the APD could be called the isolated duct of Santorini. Reporting this new variant could increase knowledge regarding the pancreatic anatomy in order to avoid misdiagnosis and to help in better understanding pancreatic diseases and their relative treatment. Clin. Anat., 33:646-652, 2020. © 2019 Wiley Periodicals, Inc.

PANCREATIC STEATOSIS: A NEW DIAGNOSIS AND THERAPEUTIC CHALLENGE IN GASTROENTEROLOGY

Fat infiltration in the pancreas is called pancreatic steatosis and it has several synonyms such as pancreatic lipomatosis, non-alcoholic fatty pancreatic disease, lipomatous pseudohypertrophy, fatty replacement, fatty pancreas and fatty infiltration. Pancreatic steatosis describes a disease ranging from infiltration of fat in the pancreas to pancreatic inflammation, and development of pancreatic fibrosis. There are multiple aetiologies of this condition, such as metabolic syndrome, alcohol intake, viral infections, toxins, congenital syndromes, etc. Pancreatic steatosis is usually diagnosed by trans-abdominal ultrasound, computed tomography scan and magnetic resonance imaging. Fatty infiltration in pancreas may lead to pancreatitis, diabetes mellitus and may be a predisposing cause of pancreatic cancer. Now a day, pancreatic steatosis is a common incidental finding during abdominal ultrasonography for other reasons and is a new challenge in Gastroenterology. But there is no guideline for pancreatic steatosis till now. In this review article, we are trying to give an overall idea (aetiologies, diagnosis, management, clinical significances) on pancreatic steatosis.

Systematic approach for assessment of imaging features in chronic pancreatitis: a feasibility and validation study from the Scandinavian Baltic Pancreatic Club (SBPC) database

PURPOSE

There is an unmet need for new systems with quantitative pancreatic imaging assessments to support better diagnosis and understand development of chronic pancreatitis (CP). The aims were to present such an approach for assessment of imaging features in CP, to apply this system in a multi-center cohort of CP patients (feasibility study), and to report inter-reader agreement between expert radiologists (validation study).

METHODS

The feasibility study included pancreatic computed tomography (CT) or magnetic resonance imaging (MRI) from 496 patients with definitive CP in the Scandinavian Baltic Pancreatic Club (SBPC) database. Images were assessed according to the new SBPC imaging system (quantitative assessments of ductal and parenchymal features). Inter-reader agreement of reported imaging parameters was investigated for 80 CT and 80 MRI examinations by two expert radiologists.

RESULTS

Reporting of the imaging features into the imaging system was deemed feasible for > 80% of CT and > 90% of MRI examinations. Quantitative assessments of main pancreatic duct diameters, presence/number/diameter of calcifications, and gland diameters had high levels of inter-reader agreement with κ-values of 0.75-0.87 and intraclass correlation coefficients of 0.74-0.97. The more subjective assessments, e.g., irregular main pancreatic duct and dilated side-ducts, had poor to moderate agreement with κ-values of 0.03-0.44.

CONCLUSION

The presented system provides a feasible mean for systematic assessment of CP imaging features. Imaging parameters based on quantitative assessment, as opposed to subjective assessments, have better reproducibility and should be preferred in the development of new grading systems for understanding pathophysiology and disease progression in CP.

Pancreatitis in the developmentally anomalous pancreas

Developmental anomalies of the pancreas include more common entities such as pancreas divisum and annular pancreas, and unusual entities such as heterotopic pancreas. While these anomalies can present a diagnostic challenge to the radiologist, when the pancreatic tissue involved in these processes develops pancreatitis, the radiographic appearance can present a diagnostic dilemma. Awareness of these pancreatic anomalies and familiarity with their appearance when inflamed is necessary to distinguish pancreatitis in the developmentally anomalous pancreas from other inflammatory or neoplastic processes.

Endoscopic Retrograde Cholangiopancreatography: Deciphering the Black and White

Endoscopic Retrograde Cholangiopancreatography (ERCP) remains the conventional method of imaging the pancreatic and biliary tree and is performed by direct injection of iodinated contrast material via the major papilla. This diagnostic procedure gained popularity in the 1970s and subsequently paved way for ERCP guided interventions such as sphincterotomy, stone retrieval and stent placement. Currently, therapeutic ERCP is more widespread than diagnostic ERCP primarily due to the availability of noninvasive imaging. Nevertheless, more than half a million ERCPs are performed annually in the United States and radiologists need to be comfortable interpreting them. The following review will familiarize the reader with the imaging appearances of biliary and pancreatic disorders on conventional ERCP, and elaborate on therapeutic ERCP with illustrative examples.

Acute pancreatitis after percutaneous insertion of metallic biliary stents in patients with unresectable pancreatic cancer

AIM

To investigate the incidence and clinical characteristics of acute pancreatitis following percutaneous insertion of metallic biliary stents in patients with unresectable pancreatic cancer. The clinical efficacy of metallic stent insertion was also evaluated.

MATERIALS AND METHODS

Data from 143 patients (75 men, 68 women; mean age, 65.8 years; range, 35-88 years) with unresectable pancreatic cancer who underwent percutaneous metallic biliary stent insertion between March 2007 and December 2017 were evaluated retrospectively. The incidence and clinical characteristics of acute pancreatitis were analysed. Stent patency and patient survival rates were calculated by Kaplan-Meier analysis.

RESULTS

Technical success was achieved in all patients. Among 31 patients with serum amylase levels above normal values (30-110 U/l), only nine had symptoms of acute pancreatitis (incidence, 6.4%). No statistically significant risk factors were identified. Pancreatitis was successfully managed with conservative treatment at a mean of 2.9 days (range, 1-4 days). The median stent patency and patient survival times were 117 days (95% confidence interval [CI], 87-148 days) and 150 days (95% CI, 125-174.9 days), respectively.

CONCLUSIONS

Acute pancreatitis was a relatively rare complication after percutaneous insertion of metallic biliary stents in patients with unresectable pancreatic cancer, and no significant risk factors were identified. Therefore, insertion of metallic biliary stents was seen to be a feasible and effective treatment approach in this patient group.

Benign and non-neoplastic tumours of the duodenum

This review study describes the problem of duodenal tumours, which are rare but important in gastrological practice. The most common location of small intestinal tumours is the duodenum, and this observation is probably partly due to the greater diagnostic availability for most proximal segments of the small intestine. Among tumours the following should be mentioned – benign: adenomas, lipomas, haemangiomas, and leiomyomas; and malignant: malignant tumours of epithelial origin, primary gastrointestinal stromal tumours, neuroendocrine tumours and carcinoids, lymphomas, sarcomas, teratomas, and secondary metastases. Early duodenal tumour recognition, especially with histological assessment, plays a crucial diagnostic role with future therapeutic implications. In recent years the prevalence of benign duodenal tumours has been rising due to a higher level of clinicians’ doubts and the convenience of gastrointestinal endoscopy; hence, knowledge of this problem is important in routine clinical practice. The method of duodenal tumour treatment should be selected on an individual basis.

Computed tomography based scoring system in a prospectively ascertained cohort of patients with chronic pancreatitis

OBJECTIVE

No standardized system is currently used to report the presence or severity of parenchymal and ductal features of chronic pancreatitis (CP) on CT scan. We report a modification to the previously proposed Cambridge classification to serve this purpose.

METHODS

Contrast-enhanced CT scans of 158 well-phenotyped patients with CP enrolled in the North American Pancreatitis Studies (NAPS2) during 2000-2014 from the University of Pittsburgh were retrospectively reviewed by a subspecialty trained abdominal radiologist. Presence and severity (score scale 0-4) of pancreatic duct (PD) dilation, obstruction and contour irregularity, pancreatic calcifications, atrophy and extent of pancreatic involvement were recorded to grade the morphological severity of CP and stratify patients into distinct morphologic patterns. Findings were also correlated with clinical features.

RESULTS

Pancreatic atrophy, calcifications, PD dilation and PD irregularity were observed in 80%, 68%, 65%, 58% cases, respectively. An obstructive stone or PD stricture was present in 63%, and 86% had diffuse pancreatic involvement. Using these features, CP was noted to be moderate or severe in 61%, and classified morphologically as obstructive with/without calcifications, calcific but non-obstructive and non-calcific/non-obstructive in 65%, 20%, 15%, respectively. Functional abnormalities but not the presence of pain generally correlated with imaging findings.

CONCLUSION

A structured scoring system can provide qualitative and quantitative assessment of imaging findings in CP and an opportunity for adoption into clinical practice and research for initial evaluation and longitudinal follow-up. Our findings need validation in a prospective cohort before widespread adoption.

Performance Characteristics of Magnetic Resonance Imaging in Patients With Pancreas Divisum

OBJECTIVE

This study was designed to assess the diagnostic accuracy of standard nonsecretin-enhanced preprocedural magnetic resonance imaging/cholangiopancreatography (MRI/MRCP) in patients with and without pancreas divisum.

METHODS

Patients undergoing MRI/MRCP followed by endoscopic retrograde cholangiopancreatography with between 2009 and 2016 were reviewed. The diagnostic accuracy of the MRI/MRCP was evaluated against the pancreatography. A subsequent independent blinded re-review performed by an expert abdominal radiologist was also evaluated. Multivariate binary logistic regression was performed to assess the impact of clinicopathologic factors on the diagnostic accuracy.

RESULTS

A total of 189 patients were included in analysis. The sensitivity, specificity, positive predictive value, and negative predictive value of MRI/MRCP for pancreas divisum were 63%, 97%, 94%, and 82% initially and 81%, 91%, 91%, and 82% on the expert review. Motion artifact, the presence of pancreatic tumor, and pancreatic necrosis were not found to significantly impact the accuracy. A normal diameter pancreatic duct (P = 0.04) and complete divisum anatomy were correlated with improved accuracy (P = 0.001).

CONCLUSIONS

Although expert review, normal duct diameter, and complete divisum are associated with increased sensitivity, pancreas divisum may be uncharacterized by preprocedural MRI in 19% to 37% of patients before the index endoscopic retrograde cholangiopancreatography.

Ectopic pancreas in the ileum: An unusual condition and our experience

BACKGROUND

Ectopic pancreas in the ileum, including lesions within Meckel diverticulum, can cause severe manifestations and complications; yet, it was seldom reported in English literature.

AIM

This study aimed to raise awareness and provide information for better clinical management of this rare yet serious condition.

METHODS

A total of 1713 cases of small bowel resection were performed in our hospital between 2009 and 2018, among which 10 cases of ileac ectopic pancreas were identified. A comprehensive retrospective review of the 10 cases was taken.

RESULTS

Five lesions were located in the ileum wall and 5 were within Meckel diverticulum. Two lesions within Meckel diverticulum were incidental; the remaining 8 lesions were all associated with abdominal pain, gastrointestinal bleeding, and anemia. Of the 5 patients with lesions in the ileum wall, computed tomography uniformly revealed ileoileal intussusceptions with masses as lead points. Capsule endoscopies were performed in 6 cases, of which 3 showed positive findings. Double-balloon enteroscopy was conducted in one case and revealed an ileal diverticulum. Therapeutically, the offending bowel segments were removed, and intussusceptions were restored except for one case in which diverticulectomy was applied. No relapse or sequela was observed in the follow-up.

CONCLUSIONS

Ileac ectopic pancreas can be seen in the ileum wall or Meckel diverticulum. The majority of the lesions found in clinical practice present with abdominal pain, gastrointestinal bleeding, and anemia. Lesions in the ileum wall often cause ileoileal intussusception. Computed tomography, capsule endoscopy, and double-balloon enteroscopy are helpful preoperative examinations. Segmental small bowel resection is the treatment of choice.