The Main Anatomical Variations of the Pancreatic Duct System: Review of the Literature and Its Importance in Surgical Practice

Meandering main pancreatic duct syndrome: a single-center cohort study and aggregated review

Background

Meandering main pancreatic duct (MMPD) refers to an uncommon ductal variant of the normal smooth curvilinear course of the pancreatic duct. More specifically, MMPD is characterized by a hairpin (reverse Z-type) or loop (loop-type) turn in the pancreatic head. It has been suggested as a predisposing factor for the development of pancreatitis. Studies regarding treatment are scarce.

Methods

We conducted a narrative review of the current literature regarding MMPD. Additionally, we present a cohort of 9 symptomatic patients treated endoscopically at our tertiary center.

Results

Seven retrospective cohort studies and 4 case reports were included in our review. Only 1 study focuses on the clinical significance of MMPD and describes a positive association between MMPD and the onset of pancreatitis, especially recurrent acute pancreatitis. Only 1 case reports an endoscopic treatment. In our cohort of 9 MMPD patients, 7 did indeed present with recurrent acute pancreatitis. Endotherapy provided substantial regression of symptoms in 6 patients, all of whom had signs of ductal hypertension.

Conclusions

Our review shows the scarcity of data regarding MMPD, especially concerning treatment, in the current literature. With our cohort, we not only hope to raise awareness of this often-neglected entity of recurrent acute pancreatitis, but also support the case for endotherapy for the first time in 9 symptomatic MMPD patients, especially in the presence of ductal hypertension.

Value of the surgical pancreatic duct anatomy and associated outcomes in pancreatic cancer

INTRODUCTION

Pancreatic cancer recurrence following surgery is a significant challenge, and personalized surgical care is crucial. Topographical variations in pancreatic duct anatomy are frequent but often underestimated. This study aimed to investigate the potential importance of these variations in outcomes and patient survival after Whipple's procedures.

METHODS

Data were collected from 105 patients with confirmed pancreatic head neoplasms who underwent surgery between 2008 and 2020. Radiological measurements of pancreatic duct location were performed, and statistical analysis was carried out using IBM SPSS.

RESULTS

Inferior pancreatic duct topography was associated with an increased rate of metastatic spread and tumour recurrence. Additionally, inferior duct topography was associated with reduced overall and recurrence-free survival. Posterior pancreatic duct topography was associated with decreased incidence of perineural sheet infiltration and improved overall survival.

DISCUSSION

These findings suggest that topographical diversity of pancreatic duct location can impact outcomes in Whipple's procedures. Intraoperative review of pancreatic duct location could help surgeons define areas of risk or safety and deliver a personalized surgical approach for patients with beneficial or deleterious anatomical profiles. This study provides valuable information to improve surgical management by identifying high-risk patients and delivering a personalized surgical approach with prognosis stratification.

Outcomes of minor versus major papilla rendez-vous for EUS-guided pancreatic duct drainage

OBJECTIVES

EUS-guided pancreatic duct drainage (EUS-PD) using rendez-vous has been suggested as a safer alternative to pancreatogastrostomy. Fibrostenotic disease in the pancreatic head may however preclude major papilla rendez-vous, leading to preferential guidewire advancement through the minor papilla. Our aim was to compare the outcomes of minor and major papilla rendez-vous.

METHODS

This is a tertiary single-center retrospective analysis of all consecutive EUS-PD procedures performed from 2015 to April 2022. EUS-PD was only performed following failed retrograde attempts. Successful EUS-PD rendez-vous cases were included and minor and major papilla procedures were compared.

RESULTS

Thirty-three patients were included in the final analysis (66.6% male, mean age 56.1 [SD±14.8] years, 54.6% active smokers). In 21 patients (63.6%), minor papilla rendez-vous was attained. Clinical success was achieved in 81.0% vs. 58.3% in the major papilla group (p = 0.230). The overall incidence of AE was similar in both groups (9 [42.9%] vs. 4 [33.3%] events, p = 0.719), with a comparable distribution in severe, moderate and mild AE. Incidence of recurrent pancreatitis was almost identical (28.6% vs. 25.0%, p = 1.000).

CONCLUSIONS

For patients with symptomatic chronic pancreatitis, EUS-PD using minor or major papilla rendez-vous attained similar results, suggesting that pancreatic duct drainage through the minor papilla can be considered as equally effective.

Incidence and Clinical Implications of Anatomical Variations in the Pancreas and Its Ductal System: A Systematic Review and Meta-Analysis

OBJECTIVE

This systematic review analyzes the anatomical variants in the pancreas and its ductal system to report on their association with pancreatic pathologies.

METHODS

We conducted a search of the MEDLINE, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS databases from their inception to July 2023. The methodological quality was assessed with the Anatomical Quality Assessment (AQUA) tool. Finally, the pooled prevalence was estimated using a random effects model.

RESULTS

55 studies were found that met the eligibility criteria. The overall prevalence of pancreas divisum (PD) was 18% (95% CI = 15-21%). The prevalence of PD associated with pancreatitis was 30% (95% CI = 1-61%).

CONCLUSIONS

An anatomical variant of the pancreas such as PD may be the cause of bile duct obstruction, resulting in various clinical complications, such as pancreatitis. Hence, knowing this variant is extremely important for surgeons, especially for those who treat the gastroduodenal region.

Dorsal pancreas agenesis, an incidental finding during acute appendicitis diagnosis; A case report

INTRODUCTION AND IMPORTANCE

Dorsal pancreas agenesis is a rare congenital anomaly characterized by the absence or severe underdevelopment of the dorsal pancreatic bud. We report a case of a man who presented with features of appendicitis only to the incidentally discovery of dorsal pancreas agenesis during the diagnosis of acute appendicitis. We describe our experience on radiological diagnostic formulation and work up.

CASE PRESENTATION

We present the case of a 45-year-old male patient who presented to the emergency department with symptoms and signs suggestive of acute appendicitis. A computed tomography scan and laboratory investigations confirmed the diagnosis of appendicitis. Incidentally, the scan also revealed the absence of dorsal pancreatic tissue, leading to the incidental diagnosis of dorsal pancreas agenesis.

CLINICAL DISCUSSION

Dorsal pancreas agenesis is often asymptomatic and can be incidentally discovered during imaging studies or surgical interventions for unrelated conditions. In our case, the initial presentation of acute appendicitis provided an opportunity for the fortuitous diagnosis of dorsal pancreas agenesis. This emphasizes the importance of comprehensive imaging reporting in patients who undergo imaging for other conditions.

CONCLUSION

This case report highlights the fortuitous discovery of dorsal pancreas agenesis during the diagnostic workup for acute appendicitis. It emphasizes the need for thorough imaging evaluation and reporting along with the importance of considering anatomical variations in patients presenting with abdominal symptoms. Increased awareness among healthcare professionals about such congenital anomalies can lead to their early recognition and appropriate management.

The Pancreas and Known Factors of Acute Pancreatitis

Pancreatitis is regarded by clinicians as one of the most complicated and clinically challenging of all disorders affecting the abdomen. It is classified on the basis of clinical, morphological, and histological criteria. Causes of acute pancreatitis can easily be identified in 75–85% of patients. The main causes of acute, recurrent acute, and chronic pancreatitis are gallstone migration and alcohol abuse. Other causes are uncommon, controversial, or unexplained. For instance, cofactors of all forms of pancreatitis are pancreas divisum and hypertriglyceridemia. Another factor that should be considered is a complication of endoscopic retrograde cholangiopancreatography: post-endoscopic retrograde cholangiopancreatography acute pancreatitis. The aim of this study is to present the known risk factors for acute pancreatitis, beginning with an account of the morphology, physiology, and development of the pancreas.

Pancreatic ductal anatomy: more than meets the eye

PURPOSE

Anatomical variations of the pancreas are relatively frequent and often understudied. The ductal system of the pancreas has multiple variations, which are not frequently reported in the literature.

MATERIALS AND METHODS

The anatomy of the pancreas was studied through macroscopic anatomical dissection on 50 organ complexes (the pancreas, spleen, and duodenum) donated to the department of human anatomy, from patients, who died of causes not related to pancreatic diseases.

RESULTS

In type I, the main pancreatic duct (Wirsung's duct, MPD) and the accessory pancreatic duct (Santorini's duct, APD) were merged but most of the head was drained by the MPD (10% of cases). In type II, the MPD and APD were merged but most of the head was drained by the APD (4% of cases). In type III, the APD was absent and the head was drained by the MPD (14% of cases). In type IV, there was an inverted pancreas divisum where the ducts did not merge but each drained a part of the head (6% of cases). Classical pancreas divisum where the ducts did not merge but each drained a part of the head was considered as type V (4% of cases). In type VI, the MPD and APD merged and each drained a part of the head (48% of cases). In type VII, the MPD and APD merged but the upper part of the head was drained by the main pancreatic duct (4% of cases). In type VIII, the MPD and APD merged but the lower part of the head was drained by the main pancreatic duct (4% of cases). In the IX type, the MPD and APD merged but the head was drained by the branches of the MPD (6% of cases).

CONCLUSIONS

There are several drainage patterns of the pancreas. In some cases, one of the ducts provides more drainage of the gland than the other. This is clinically relevant since blockage of the main source of drainage leads to pancreatic juice stasis. It also explains cases when partial or total blockage of the duct results in the pancreatitis of an isolated zone.

Congenital Anomalies of the Pancreas: Various Clinical Manifestations and Their Impact on Pancreatic Diseases and Outcomes

Background and objective: Congenital anomalies of the pancreas are relatively uncommon. Most of these are asymptomatic and are detected incidentally, but can present with a variety of clinical manifestations like pancreatitis, duodenal obstruction, biliary obstruction, and rarely malignancy. Here in our study, we describe various congenital anomalies of the pancreas associated with various clinical manifestations, its management strategies, and outcomes. The aim was to study the various clinical manifestations of and management strategies for pancreatic diseases associated with congenital anomalies of the pancreas and their outcomes.

Methods: A retrospective analysis of a prospectively maintained institutional database of 14 patients, admitted over a period of three years from June 2019 to May 2022, who were treated for different clinical manifestations of various congenital anomalies of the pancreas and their outcomes was done at our institution.

Results: The total number of congenital anomalies of the pancreas in our study was 14 out of whom 7 (50%) were males and 7 (50%) females. The mean age of the patients was 37 years. The most common congenital anomaly was pancreatic divisum in six (42.9%) cases. The most common clinical manifestation was acute pancreatitis in four (28.6%) cases. One (7.1%) case was incidentally detected intraoperatively for another condition. Eight (57.1%) patients underwent surgical intervention and six (42.9%) patients were medically managed. Mortality occurred in two (14.3%) cases. Associated alcohol consumption was seen in 2 (14.3%) cases; 10 (71.4%) patients had no comorbidities while 4 (28.6%) patients had diabetes mellitus. Out of eight (57.1%) surgical patients, two (25%) had Clavien-Dindo grade I and one patient (12.5%) grade V complications.

Conclusion: Congenital anomalies of the pancreas can be associated with a variety of clinical manifestations; their management strategies and outcomes are no different from patients with the same clinical manifestations with normal pancreatic development.

Double plastic stent implantation for recurrent acute pancreatitis with incomplete pancreas divisum: a case report and literature review

Pancreas divisum (PD) is a common pancreatic malformation caused by the failure of fusion between ventral and dorsal pancreatic ducts. There is a small branch of communication between the two systems in incomplete PD, and this variation has an incidence of 15%. A 43-year-old female patient presented to our department with recurrent abdominal pain. Magnetic resonance cholangiopancreatography (MRCP) showed that the ventral pancreatic duct was curved, with a local pouchlike dilatation. Endoscopic ultrasonography supported the diagnosis of incomplete PD and showed a thin branch of communication between ventral and dorsal pancreatic ducts. Endoscopic retrograde cholangiopancreatography (ERCP) and papillotomy of the minor papilla with double plastic stent implantation were performed. One pancreatic plastic stent was inserted across the minor and major papilla over the guide wire, creating a U-shape. The other wire-guided plastic stent was inserted through the minor papilla into the dorsal pancreatic duct. The pancreatic fluid drained smoothly after stent placement. During the 6-month follow-up, the patient remained well, without recurrence of pancreatitis.

Clinical outcome of endoscopic therapy in patients with symptomatic pancreas divisum: a Dutch cohort study

Background and study aims  Although the majority of patients with pancreas divisum (PDiv) are asymptomatic, a subgroup present with recurrent pancreatitis or pain for which endoscopic therapy may be indicated. The aim of this study was to evaluate success rates and long-term outcomes of endoscopic treatment in patients with symptomatic PDiv. Patients and methods  A multicenter, retrospective cohort study was performed. Patients with symptomatic PDiv presenting with recurrent acute pancreatitis (RAP), chronic pancreatitis (CP), or chronic abdominal pancreatic-type pain (CAP) who underwent endoscopic retrograde cholangiopancreatography (ERCP) between January 2000 and December 2019 were included. The primary outcome was clinical success, defined as either no recurrent episode of acute pancreatitis (AP) for RAP patients, no flares for CP patients, or absence of abdominal pain for patients with CAP after technically successful ERCP. Results  In 60 of 81 patients (74.1 %) a technically successful papilla minor intervention was performed. Adverse events were reported in 30 patients (37 %), with post-ERCP pancreatitis in 18 patients. The clinical success rate for patients with at least 3 months of follow-up was 42.6 %, with higher rates of success among patients presenting with RAP (44.4 %) as compared to those with CP (33.3 %) or CAP (33.3 %). Long-term sustained response was present in 40.9 % of patients with a technically successful intervention. In patients with RAP who did not completely respond to treatment, the mean number of AP episodes after treatment decreased significantly from 3.5 to 1.1 per year, and subsequently the interval between AP episodes increased from 278 to 690 days ( P  = 0.0006). A potential predictive factor of failure of clinical success after technically successful ERCP, at univariate analysis, was male sex (OR = 0.25, P  = 0.02). Conclusions  Endoscopic therapy in patients with symptomatic PDiv is moderately effective, with its highest yield in patients presenting with RAP. Future studies are needed to assess factors predictive for success of endoscopic therapy and potential risk factors for relapse after ERCP.

Current advances in the management of chronic pancreatitis

Chronic pancreatitis is characterized by irreversible destruction of pancreatic parenchyma and its ductal system resulting from longstanding inflammation, leading to fibrosis and scarring due to genetic, environmental, and other risk factors. The diagnosis of chronic pancreatitis is made based on a combination of clinical features and characteristic findings on computed tomography or magnetic resonance imaging. Abdominal pain is the most common symptom of chronic pancreatitis. The main aim of treatment is to relieve symptoms, prevent disease progression, and manage complications related to chronic pancreatitis. Patients who do not respond to medical treatment or not a candidate for surgical treatment are usually managed with endoscopic therapies. Endoscopic therapies help with symptoms such as abdominal pain and jaundice by decompression of pancreatic and biliary ducts. This review summarizes the risk factors, pathophysiology, diagnostic evaluation, endoscopic treatment of chronic pancreatitis, and complications. We have also reviewed recent advances in endoscopic retrograde cholangiopancreatography and endoscopic ultrasound-guided therapies for pancreatic duct obstruction due to stones, strictures, pancreatic divisum, and biliary strictures.

Ansa pancreatica: a rare cause of acute recurrent pancreatitis

Acute pancreatitis is an inflammation of the pancreas that can be caused in rare situations by ansa pancreatica, it is a rare anatomic variation of the pancreatic ducts. It is a communication between the main pancreatic duct (Wirsung) and the accessory pancreatic duct (Santorini). We report a case of the patient, in a 44-year-old, non-alcoholic, hospitalized for acute pancreatitis stage C of Baltazar. A magnetic resonance Cholangiopancreatography (MRCP) was performed which showed a gallstone and ansa pancreatica, than an endoscopic retrograde cholangiopancreatography (ERCP) revealed an ansa pancreatica with a common bile duct clear, a sphincterotomy of the major papilla was performed. It is still not clear whether the presence of these two pathologies is a coincidence or if the ansa pancreatica is the cause of acute pancreatitis. New studies are necessary to clarify these points.

Pancreatic Duct Variations and the Risk of Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis

Endoscopic retrograde cholangiopancreatography (ERCP) is an important diagnostic and therapeutic procedure in the management of biliary and pancreatic disorders. Despite advances in ERCP facilities and techniques, pancreatitis remains the most common and feared complication of this procedure. The technical challenges of ERCP could be further compounded by variations in the configuration of the pancreatic ductal system. As a result, the knowledge of these variations and their potential role in the development of post-ERCP pancreatitis (PEP) is essential to any successful risk reduction strategy. This review provides an overview of the anatomy and embryological basis of pancreatic duct variations, as well as explore the different types and prevalence of these variations. Also, we discuss the mechanisms of PEP and provide evidence supporting a link between the variations and PEP using published data

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.

Biliary anatomy and pancreatic duct variations: A cross-sectional study

BACKGROUND/AIM

Biliary tree and pancreatic duct can appear in different variations whose proper understanding is obligatory for surgeons. Magnetic resonance cholangiopancreatography (MRCP) is considered a safe and accurate tool for evaluating biliary tree and pancreatic duct. Typical anatomy for right hepatic duct (RHD) and left hepatic duct (LHD) is reported as 57% and 63%, respectively. The most common (4-10%) pancreatic anomaly is divisum. In the present study, we evaluated and determined the prevalence of biliary tree and pancreatic duct variations among patients at a university hospital.

MATERIALS AND METHODS

The MRCP records of 370 patients from 2015 to 2017 were obtained for cross-sectional study. Images were retrospectively reviewed for variations by two independent senior radiologists. Demographic data were obtained for all the patients. Huang et al. classification was used for RHD and LHD variations. The cystic duct was reported based on its course and insertion pattern. The pancreatic duct was observed for the presence of divisum, its course, and configuration.

RESULTS

Three hundred and twenty-five patients were included in the final study. Most commonly observed variant for RHD were A1 (34.2%) and A2 (32.2%). For LHD, B1 (71.4%) was the most common variant. Cystic duct insertion was commonly seen as right lateral insertion (27.7%). Pancreatic divisum was observed in 0.6% of cases. Nationality, origin, and gender-specific variations were obtained.

CONCLUSION

Variations in biliary anatomy and pancreatic duct are very diverse and extend from the intrahepatic biliary system down to the pancreas. Performing a similar study on a larger population is mandatory to illustrate the range of variations present within the community.

Clinical importance of main pancreatic duct variants and possible correlation with pancreatic diseases

Background: Except for pancreas divisum (PD), the prevalence of anatomic variants of the main pancreatic duct (MPD) seems to be insufficiently investigated. To date, their role in the occurrence of pancreatic exocrine insufficiency (PEI) and morphological changes suggestive of chronic pancreatitis (CP) has remained unclear.Methods: A systematic review was performed, searching MEDLINE and Web of Science, limited to articles published between 1960 and 1 June 2019.Results: Our review included a total number of 3234 subjects. The most common variant of MPD was type 3, followed by type 1, indicating MPD drainage pattern into major papilla (MP) as the most frequent. A sub-variant of type 3, known as 'reverse pancreas divisum' had a prevalence of 2.2%. Type 4 variant- PD, was found in 6.4% of all cases. The most common sub-variant of PD was complete PD, followed by incomplete PD and variant with MPD as only pancreatic duct. Type 5 variant (including ansa pancreatica) was present in 2.9% of subjects. Apart from one study with a significantly higher frequency of morphological changes suggestive of CP in patients with ansa pancreatica, the studies stated no significant association between pancreatic disease and MPD variants. Furthermore, only one study examined the influence of MPD variants on exocrine pancreatic function. Although equivocal, this association is most likely found to be insignificant.Conclusion: To elucidate linkage between MPD variants and the occurrence of chronic pancreatitis and impairment of pancreatic exocrine function, further clinical investigations are warranted.

Synchronous Periampullary Tumors in a Patient With Pancreas Divisum and Neurofibromatosis Type 1

INTRODUCTION

In this study, we describe for the first time a Neurofibromatosis type 1 patient with pancreas divisum, multiple periampullary tumors and germline pathogenic variants in NF1 and CFTR genes.

CASE REPORT

A 62-year-old female NF1 patient presented with weakness, choluria, nausea, and diffuse abdominal pain to an emergency room service. Magnetic resonance imaging revealed an abdominal mass involving the periampullary region and pancreas divisum. After surgical resection, three synchronous neoplasms were detected including two ampullary tumors (adenocarcinoma of the major ampulla and a neuroendocrine tumor of the minor ampulla) and a gastrointestinal stromal tumor (GIST). Germline multigene panel testing (MGPT) identified two pathogenic heterozygous germline variants: NF1 c.838del and CFTR c.1210-34TG[12]T[5].

CONCLUSION

This is the first report of a Neurofibromatosis type 1 patient with pancreas divisum and multiple periampullary tumors harboring pathogenic germline variants in NF1 and CFTR genes. The identification of two germline variants and a developmental anomaly in this patient may explain the unusual and more severe findings and underscores the importance of comprehensive molecular analyses in patients with complex phenotypes.

Diagnosis and treatment of pancreas divisum: A literature review

BACKGROUND

Pancreas divisum is a congenital embryological disease caused by a lack of fusion between the ventral and dorsal pancreatic ducts in the early stages of embryogenesis. Recurrent acute pancreatitis, chronic pancreatitis or chronic abdominal pain are the main clinical syndromes at presentation and occur in only 5% of the patients with pancreas divisum. This review aimed to discuss diagnosis and treatment strategies in patients with symptomatic pancreas divisum.

DATA SOURCES

We report a literature review from 1990 up to January 2018 to explore the various diagnostic modalities and surgical techniques and results reported in the surgical treatment of pancreas divisum.

RESULTS

There are limited reports available on this topic in the literature. We analyzed and described the main indications in the treatment of pancreas divisum, focusing on surgical treatment and a discussion of the different approaches. Furthermore, we report the results from our experience in two cases of pancreas divisum treated by pancreatic head resection with segmental duodenectomy (the Nakao procedure).

CONCLUSIONS

Pancreas divisum is a common pancreatic malformation in which only a few patients develop a symptomatic disease. Surgical treatment is needed in case of endoscopic drainage failure and in cases complicated with chronic pancreatitis and local complications. Many techniques, of greater or lesser complexity, have been proposed.