Accuracy of magnetic resonance cholangiopancreatography in identifying pancreatic duct disruption

The role of MRCP for preventing pancreatic fluid collection recurrence after EUS-guided drainage of walled-off necrosis

BACKGROUND AND AIMS

Pancreatic fluid collections (PFCs) may recur after initial successful endoscopic drainage of walled-off necrosis (WON), most commonly due to disconnected pancreatic duct syndrome (DPDS). The primary aim of this study was to assess the role of MRCP for identifying DPDS to guide appropriate management and prevent PFC recurrence.

METHODS

Patients with WON undergoing lumen-apposing metal stent drainage of a PFC were retrospectively identified and categorized as those with MRCP versus those without MRCP before removal of transmural stents. Data on patient demographic characteristics, procedural details, cross-sectional imaging, and recurrence rates were collected through chart review.

RESULTS

A total of 121 patients with WON were identified, of whom 44 (36.4%) had an MRCP before transmural stent removal. In patients without MRCP, 13 (16.8%) of 77 had PFC recurrence versus 0 of 44 (0%; P = .003) in those with MRCP. MRCP identified DPDS in 12 (27.2%) patients, all of whom were managed with indefinite drainage with double-pigtail plastic stents without recurrence. In the group without MRCP, PFCs recurred at a median interval of 284 days (interquartile range, 182-618 days) after transmural stent removal. Among the 13 patients with PFC recurrence, 11 (85%) had undiagnosed DPDS detected on subsequent imaging, of whom 9 were subsequently managed with indefinite double-pigtail plastic stents, with no further PFC recurrence.

CONCLUSIONS

Patients with WON who underwent MRCP before transmural stent removal had a lower rate of PFC recurrence largely due to the identification of DPDS with appropriate endoscopic management.

Percutaneous Biopsy and Drainage of the Pancreas

Percutaneous biopsy and drainage of pancreatic lesions, though less frequent due to advancements in endoscopic techniques, remain vital skills for interventional radiologists. This review details the indications, options, approaches, and technical considerations for pancreatic biopsy and (peri)pancreatic fluid drainage by examining a comprehensive range of literature. The importance of a multidisciplinary approach is emphasized to ensure optimal patient care and outcomes, highlighting current best practices and recent advancements.

Disconnected pancreatic duct syndrome: diagnostic and therapeutic challenges and future directions

INTRODUCTION

Disconnected pancreatic duct syndrome (DPDS) is a pathological condition that causes various symptoms due to the continuous secretion of pancreatic enzymes from the pancreas upstream, which has been separated due to disconnection of the pancreatic duct (DPD) for various reasons.Acute necrotizing pancreatitis includes a certain probability of DPDS appearance, which makes it necessary to provide various treatments for DPDS. Furthermore, DPDS can impact long-term results, such as recurrence and impaired pancreatic function. Although the development of various modalities has contributed to diagnosis and treatment, especially less invasive endoscopic therapy, DPDS is often overlooked, and the diagnosis can be delayed due to the lack of consensus on its definition and classification. This review summarizes the current knowledge and challenges of DPDS and discusses the optimal strategy for its diagnosis and treatment, as well as future perspectives.

AREAS COVERED

Given the lack of established definition, diagnosis, and treatment of DPDS, we conducted a thorough review of the existing literature.

EXPERT OPINION

It is emphasized that a standardized definition and classification of DPDS is essential for designing and conducting clinical studies to address current unmet needs in managing patients with DPDS.

Magnetic resonance imaging in the evaluation and management of acute pancreatitis: a review of current practices and future directions

Acute pancreatitis is a condition marked by inflammation of the pancreas and surrounding tissues. While the majority of cases of acute pancreatitis are mild, a minority of severe cases are the primary contributors to the morbidity and mortality attributed to this condition. Retroperitoneal morphologic changes can be detected by utilization of various imaging modalities, and their accurate evaluation is crucial for effective management. Acute pancreatitis is commonly diagnosed using computed tomography (CT). However, there are certain clinical scenarios where magnetic resonance imaging (MRI) may have superiority over CT. In particular, MRI is useful in cases where patients cannot receive iodinated CT contrast, or where there is a need to investigate the underlying cause of acute pancreatitis. Additionally, MRI can be utilized to evaluate ductal disconnection and guide interventions for necrotic collections. The unique features of MRI can be particularly useful, including its ability to provide superior contrast resolution and to offer greater functional information through techniques such as diffusion-weighted imaging. The aim of this review is to discuss the MRI assessment of individuals with acute pancreatitis. Additionally, the recent advances in MRI for evaluation of acute pancreatitis will also be introduced.

Recurrent acute pancreatitis: a harbinger for irreversible chronic pancreatitis

Recurrent acute pancreatitis is beginning to be recognized as an intermediary stage in the continuous spectrum between acute and chronic pancreatitis. It is crucial to identify this disease stage and intervene with diagnostic and therapeutic modalities to prevent the painful and irreversible condition of chronic pancreatitis. We review the recent advances in diagnosing and managing this important 'call for action' condition.

Magnetic resonance imaging for acute pancreatitis in type 2 diabetes patients

Type 2 diabetes mellitus (T2DM) and its complications have significantly increased the burden of mortality and disability globally, making diabetes one of the most dangerous and prevalent chronic diseases. Acute pancreatitis (AP) is one of the most frequent gastrointestinal causes for hospital admission, which is a common exocrine pancreatic inflammatory disease that can cause severe abdominal pain and multiple organ dysfunction. There is an inseparable relationship between AP and diabetes. Diabetes is a high risk factor of AP, and patients with AP can develop pancreatogenic diabetes. In T2DM patients, the incidence rate of AP is significantly higher than that of the general population, and the clinical symptoms are more severe, with the majority of cases being moderate to severe AP. This review briefly introduces the pathogenesis and clinical features of AP in T2DM patients, focusing on the magnetic resonance imaging (MRI) manifestations of AP in T2DM patients. Our aim is to evaluate the severity of AP in patients with T2DM by MRI, so as to help clinicians assess the patient's condition and prognosis.

Management of Disconnected Pancreatic Duct

Disconnected pancreatic duct (DPD) is common after acute necrotizing pancreatitis (ANP). Its clinical implications vary according to the course of disease. In the early phase of ANP, parenchymal necrosis along with disruption of pancreatic duct cause acute necrotic collection that evolves into walled-off necrosis (WON). In the later phase, DPD becomes evident as confirmed by magnetic resonance cholangiopancreatography. Clinical manifestations of DPD can vary from being asymptomatic, recurrent pain, recurrent pancreatic fluid collection (PFC), obstructive pancreatitis, or external pancreatic fistula (EPF). Few patients develop new-onset diabetes. Long-term indwelling plastic stents have been proposed to prevent the recurrent PFC.

Transpapillary Stenting Improves Treatment Outcomes in Patients Undergoing Endoscopic Transmural Drainage of Ductal Disruption-Associated Pancreatic Fluid Collections

INTRODUCTION

Endoscopic transmural drainage (TMD) has been accepted as the preferred therapy for symptomatic pancreatic fluid collections (PFCs). Recurrence of PFCs presents a unique challenge in patients with disrupted pancreatic duct (PD). We aimed to evaluate whether transpapillary drainage (TPD) provides additional benefits to TMD in patients with PD disruption.

METHODS

This was a multicenter retrospective study. Consecutive patients who underwent TMD, TPD, or combined drainage (CD) of PFCs were included. The primary outcome was to compare PFC recurrence among different groups. The secondary outcomes were the technical success rate, length of hospital stay, and procedure-related complications.

RESULTS

A total of 153 patients, which consists of 57 patients with pancreatic pseudocysts and 96 patients with walled-off necrosis, were included. PFC recurrence was more common in patients with PD disruption than those with an intact main duct (19% vs 1.4%, P < 0.001). PD disruption was identified as a major risk factor of PFC recurrence by univariable and multivariable analyses. The recurrence rate of CD was significantly lower than TMD only or TPD only (6.5% vs 15.4% vs 22.7%, P < 0.01). The length of hospital stay of CD was significantly shorter than TMD only or TPD only (5 [3.0-9.0] vs 7.0 [5.0-12.0] vs 9 [7.0-16.0], P < 0.001). Dual-modality drainage did not increase procedure-related complications compared with TMD only (13.0% vs 12.8%, P > 0.05). Partial PD disruption was bridged in 87.3% cases while complete PD disruption was reconnected in 55.2% cases. Although statistically not significant, the clinical success rate in walled-off necrosis cases with actively bridged ducts was much higher than those with passively bridged ducts (76.9% vs 40%).

DISCUSSION

Transpapillary pancreatic duct stenting seems to improve the efficacy of endoscopic TMD of pancreatic duct disruption-associated PFCs by reducing the recurrence rate and shortening the length of hospital stay.

Endoscopic management of pancreatic fluid collections with disconnected pancreatic duct syndrome

Disconnected pancreatic duct syndrome (DPDS) is an important and common complication of acute necrotizing pancreatitis. Endoscopic approach has been established as the first-line treatment for pancreatic fluid collections (PFCs) with less invasion and satisfactory outcome. However, the presence of DPDS significantly complicates the management of PFC; besides, there is no standardized treatment for DPDS. The diagnosis of DPDS presents the first step of management, which can be preliminarily established by imaging methods including contrast-enhanced computed tomography, ERCP, magnetic resonance cholangiopancreatography (MRCP), and EUS. Historically, ERCP is considered as the gold standard for the diagnosis of DPDS, and secretin-enhanced MRCP is recommended as an appropriate diagnostic method in existing guidelines. With the development of endoscopic techniques and accessories, the endoscopic approach, mainly including transpapillary and transmural drainage, has been developed as the preferred treatment over percutaneous drainage and surgery for the management of PFC with DPDS. Many studies concerning various endoscopic treatment strategies have been published, especially in the recent 5 years. Nonetheless, existing current literature has reported inconsistent and confusing results. In this article, the latest evidence is summarized to explore the optimal endoscopic management of PFC with DPDS.

Short- and long-term outcomes of a disruption and disconnection of the pancreatic duct in necrotizing pancreatitis: a multicenter cohort study in 896 patients : Disrupted pancreatic duct in acute pancreatitis

OBJECTIVES

Necrotizing pancreatitis may result in a disrupted or disconnected pancreatic duct (DPD) with the potential for long lasting negative impact on a patient's clinical outcome. There is a lack of detailed data on the full clinical spectrum of DPD which is critical for the development of better diagnostic and treatment strategies.

METHODS

We performed a long-term post-hoc analysis of a prospectively collected nationwide cohort of 896 patients with necrotizing pancreatitis (2005-2015). The median follow-up after hospital admission was 75 months (P25-P75:41-151). Clinical outcomes of patients with and without DPD were compared using regression analyses, adjusted for potential confounders. Predictive features for DPD were explored.

RESULTS

DPD was confirmed in 243 (27%) of the 896 patients and resulted in worse clinical outcomes during both the patient's initial admission and follow-up. During hospital admission, DPD was associated with an increased rate of new-onset intensive care unit admission (adjusted-OR2.52 [95%-CI 1.62-3.93]), new-onset organ failure (adjusted-OR2.26 [95%-CI 1.45-3.55]), infected necrosis (adjusted-OR4.63 [95%-CI 2.87-7.64]) and pancreatic interventions (adjusted-OR7.55 [95%-CI 4.23-13.96]). During long-term follow-up, DPD increased the risk of pancreatic intervention (adjusted-OR9.71 [95%-CI 5.37-18.30], recurrent pancreatitis (adjusted-OR2.08 [95%-CI 1.32-3.29]), chronic pancreatitis (adjusted-OR2.73 [95%-CI 1.47-5.15]) and endocrine pancreatic insufficiency (adjusted-OR1.63 [95%-CI 1.05-2.53]).Central or subtotal pancreatic necrosis on computed tomography (CT), (OR9.49 [95%-CI 6.31-14.29] and a high levels of serum C-reactive protein (CRP) in the first 48 hours after admission (per 10 points increase, OR1.02 [95%-CI 1.00-1.03] were identified as independent predictors for developing DPD.

CONCLUSIONS

At least one of every four patients with necrotizing pancreatitis suffer from DPD which is associated with detrimental, short and long-term interventions and complications. Central and subtotal pancreatic necrosis and high levels of serum CRP in the first 48 hours are independent predictors for DPD.

Endoscopic Management of Complications in Chronic Pancreatitis

PURPOSE OF REVIEW

Management of complications in patients with chronic pancreatitis is often suboptimal. This review discusses detailed endoscopic approaches for managing complications in CP.

LITERATURE FINDINGS

CP is characterized by progressive and irreversible destruction of pancreatic parenchyma and ductal system resulting in fibrosis, scarring, and loss of glandular function. Abdominal pain remains is the most common symptom of the disease and the main aim of medical, endoscopic, and surgical therapy is to help relieve symptoms, prevent disease progression, and manage complications related to CP. In fact, advances in our understanding of CP have improved medical care and quality of life in these patients. With significant sequela, morbidity and a progressive nature, a thorough understanding of the pathophysiology, natural course, diagnostic approaches, and optimal management strategies for this disease is warranted. The existing modalities and new innovations in this field are safe, effective, and likely to have a positive impact on management of complication in CP whenever used in the right context.

Radiological criteria for disconnected pancreatic duct syndrome: a targeted literature review

INTRODUCTION

In patients with acute necrotizing pancreatitis (ANP), parenchymal necrosis may involve the pancreatic duct, isolating a segment of the pancreas that remains functional but drains its secretions into the peripancreatic fluid collections, leading to disconnected pancreatic duct syndrome (DPDS). DPDS is an important complication of ANP associated with long-term morbidity and mortality. Unfortunately, this critical entity is under-recognized by radiologists. Endoscopic retrograde cholangiopancreatography (ERCP) is considered the gold standard for diagnosing and treating such patients. However, considering the invasiveness of the ERCP, a noninvasive diagnosis based on radiological tests is desirable. Radiological literature concerning the diagnosis of DPDS is scarce, and there is substantial ambiguity regarding the radiological definitions of DPDS.

AREAS COVERED

Considering the scarcity of published literature regarding the reliable radiologic diagnosis of DPDS, we performed a thorough review of the existing literature to identify definitions and features of this entity on computed tomography (CT) and magnetic resonance imaging (MRI).

EXPERT OPINION

Existing literature regarding radiologic diagnosis of DPDS was reviewed and analyzed and a comprehensive imaging definition of DPDS was proposed.

Safety and Efficacy of Early Endotherapy in Management of Pancreatic Ascites: Western Indian Experience

Background Pancreatic ascites is rare but a known complication of pancreatitis. We aimed to study the timings, safety, and efficacy of therapeutic approaches in its management and the outcomes.

Methods We retrospectively studied patients with pancreatic ascites managed in the past 5 years at a single tertiary care center. Therapeutic approaches included conservative therapy, early endoscopic therapy, and surgery. We used descriptive statistics to summarize characteristics of the study population, and performed univariate and binary logistic regression analyses to compare treatment outcomes.

Results Of the 125 patients screened, 70 (male, 81.4%) were included. Disruption in the pancreatic duct (PD) was seen in 51.4% of patients on magnetic resonance cholangiopancreatography (MRCP) and 73.3% of patients on endoscopic retrograde cholangiopancreatography (ERCP). The PD in the body region (46.7%) was the most frequent site of disruption. Early endotherapy included a stent bridging the disruption site in 63.3% of patients and sphincterotomy in 76.7% of patients with a median time to ERCP from symptom onset being 8.5 days. The success rate in early endotherapy was 81.7%, while the recurrence rate was 8%. For conservative therapy only, the success rate was 60% with recurrence in two-thirds. The variables crucial in the success of endotherapy were a partial disruption (p < 0.001), ductal disruption site (p = 0.004), sphincterotomy (p = 0.013), and a bridging stent (p = 0.001). Significant pancreatic necrosis (p < 0.001) and intraductal calculi (p = 0.002) were the factors responsible for failure in endotherapy.

Conclusions Early endotherapy is safe and effective in the treatment of pancreatic ascites. The efficacy of endotherapy is augmented by PD stenting combined with pancreatic sphincterotomy and a bridging stent.

Diagnosis and treatment of pancreatic duct disruption or disconnection: an international expert survey and case vignette study

BACKGROUND

Pancreatic duct disruption or disconnection is a potentially severe complication of necrotizing pancreatitis. With no existing treatment guidelines, it is unclear whether there is any consensus among experts in clinical practice. We evaluated current expert opinion regarding the diagnosis and treatment of pancreatic duct disruption and disconnection in an international case vignette study.

METHODS

An online case vignette survey was sent to 110 international expert pancreatologists. Expert selection was based on publications in the last 5 years and/or participation in development of IAP/APA and ESGE guidelines on acute pancreatitis. Consensus was defined as agreement by at least 75% of the experts.

RESULTS

The response rate was 51% (n = 56). Forty-four experts (79%) obtained a MRI/MRCP and 52 experts (93%) measured amylase levels in percutaneous drain fluid to evaluate pancreatic duct integrity. The majority of experts favored endoscopic transluminal drainage for infected (peri)pancreatic necrosis and pancreatic duct disruption (84%, n = 45) or disconnection (88%, n = 43). Consensus was lacking regarding the treatment of patients with persistent percutaneous drain production, and with persistent sterile necrosis.

CONCLUSION

This international survey of experts demonstrates that there are many areas for which no consensus existed, providing clear focus for future investigation.

Impact of disconnected pancreatic duct syndrome on endoscopic ultrasound-guided drainage of pancreatic fluid collections

BACKGROUND

Endoscopic intervention for pancreatic fluid collections (PFCs) with disconnected pancreatic duct syndrome (DPDS) has been associated with failures and increased need for additional endoscopic and non-endoscopic interventions. The primary aim of this study was to determine the outcomes of endoscopic ultrasound (EUS)-guided transmural drainage of PFCs in patients with DPDS.

METHODS

In patients undergoing EUS-guided drainage of PFCs from January 2013 to January 2018, demographic profiles, procedural indications and details, adverse events, outcomes, and subsequent interventions were retrospectively collected. Overall treatment success was determined by PFC resolution on follow-up imaging or stent removal without recurrence.

RESULTS

EUS-guided drainage of PFCs was performed in 141 patients. DPDS was present in 57 of them (40 %) and walled-off necrosis was the most frequent type of PFC (55 %). DPDS was not associated with lower clinical success, increased number of repeat interventions, or increased time to PFC resolution. Patients with DPDS were more likely to be treated with permanent transmural plastic double-pigtail stents (odds ratio [OR] 6.4; 95 % confidence interval [CI] 2.5 - 16.5; P < 0.001). However, when stents were removed, DPDS was associated with increased PFC recurrence after stent removal (OR 8.0; 95 %CI 1.2 - 381.8; P = 0.04).

CONCLUSIONS

DPDS frequently occurs in patients with PFCs but does not negatively impact successful resolution. DPDS is associated with increased PFC recurrence after stent removal.

Clinical-radiological characteristics and intestinal microbiota in patients with pancreatic immune-related adverse events

BACKGROUND

The pancreatic immune-related adverse event (irAE) is a rare but increasingly occurrence disease with limited knowledge, which was associated with the use of immune checkpoint inhibitors (ICIs).

METHODS

In this case series study of pancreatic irAE patients, clinical and radiological manifestations are summarized. Baseline and post-treatment fecal microbiota of immune-related acute pancreatitis (irAP) patients were analyzed by the 16 s rDNA amplicon sequencing method.

RESULTS

A total of six patients were enrolled into the study, and the onset of pancreatic irAEs occurred a median of 105 days after a median of 4.5 cycles with immune checkpoint inhibitors (ICIs). All patients had an effective response to ICIs. Abdominal pain was the main clinical manifestation. Serum amylase (sAMY) and lipase (sLIP) had dynamic changes parallel to clinical severity. Contrast-enhanced computed tomography (CT) did not accurately reveal the level of inflammation. However, magnetic resonance imaging (MRI) was a sensitive imaging method which showed decreased and increased signal intensity of pancreatic parenchyma in T1-weighted fat-saturated and diffusion-weighted imaging, respectively. Glucocorticoids were the main treatment with a rapid initial effect followed by a slow improvement. After reinitiation of ICI therapy, pancreatic irAEs either deteriorated, remained stable or the patient developed severe pancreatic β-cell destruction without irAP recurrence. The baseline microbiota of irAP had low Bacteroidetes/Firmicutes ratio at phylum level, low relative abundance of Alistipes, Bacteroides and high Lachnospiraceae at genus level, compared to levels of pancreatic β-cell destruction and post-treatment of irAP.

CONCLUSIONS

Pancreatic irAE patients had corresponding abdominal pain and increase in sAMY/sLIP. MRI was found to be an ideal imaging modality. Treatment with glucocorticoids were the main approach. The microbiota showed relative changes at baseline and during treatment.

Various Modalities Accurate in Diagnosing a Disrupted or Disconnected Pancreatic Duct in Acute Pancreatitis: A Systematic Review

BACKGROUND

Severe pancreatitis may result in a disrupted pancreatic duct, which is associated with a complicated clinical course. Diagnosis of a disrupted pancreatic duct is not standardized in clinical practice or international guidelines. We performed a systematic review of the literature on imaging modalities for diagnosing a disrupted pancreatic duct in patients with acute pancreatitis.

METHODS

A systematic search was performed in PubMed, Embase and Cochrane library databases to identify all studies evaluating diagnostic modalities for the diagnosis of a disrupted pancreatic duct in acute pancreatitis. All data regarding diagnostic accuracy were extracted.

RESULTS

We included 8 studies, evaluating five different diagnostic modalities in 142 patients with severe acute pancreatitis. Study quality was assessed, with proportionally divided high and low risk of bias and low applicability concerns in 75% of the studies. A sensitivity of 100% was reported for endoscopic ultrasound and endoscopic retrograde cholangiopancreatography. The sensitivity of magnetic resonance cholangiopancreatography with or without secretin was 83%. A sensitivity of 92% was demonstrated for a combined cohort of secretin-magnetic resonance cholangiopancreatography and magnetic resonance cholangiopancreatography. A sensitivity of 100% and specificity of 50% was found for amylase measurements in drain fluid compared with ERCP.

CONCLUSIONS

This review suggests that various diagnostic modalities are accurate in diagnosing a disrupted pancreatic duct in patients with acute pancreatitis. Amylase measurement in drain fluid should be standardized. Given the invasive nature of other modalities, secretin-magnetic resonance cholangiopancreatography or magnetic resonance cholangiopancreatography would be recommended as first diagnostic modality. Further prospective studies, however, are needed.

Pancreatic ascites and Pleural Effusion in Children: Clinical Profile, Management and Outcomes

BACKGROUND

Pancreatic ascites (PA) and pleural effusion (PPE) are rarely encountered in children. They develop due to disruption of the pancreatic duct (PD) or leakage from an associated pancreatic fluid collection (PFC). The literature on childhood PA/PPE and its management is scarce.

METHODS

A retrospective review of children with PA/PPE diagnosed and managed at our center over the last 4 years was performed. The clinical, biochemical, radiological and management profiles were analyzed. Conservative management included nil per oral, octreotide and drainage using either percutaneous catheter or repeated paracentesis. Endotherapy included endoscopic retrograde cholangiopancreatography (ERCP) and transpapillary stenting.

RESULTS

Of the 214 children with pancreatitis, 15 (7%) had PA/PPE. Median age was 9 years with a third under 2 years. Median ascitic fluid amylase was 8840 U/L and all had elevated protein (>2.5 g/dl) and low serum ascites-albumin gradient ascites (<1.1). While PA/PPE was the first manifestation of underlying chronic pancreatitis (CP) in 10 children (67%), trauma was seen in 4 (26%) and hypertriglyceridemia in 1 (7%). On imaging, PD disruption could be identified in 10 (67%) children. ERCP and stenting was done in 10 children. Conservative management alone (n = 4) and endotherapy (n = 10) was successful in 93% with only one requiring surgery. The younger children (n = 4), were managed conservatively and only 1 of them required surgery. Resolution of PA/PPE was achieved in all with no recurrences.

CONCLUSIONS

Conservative management and ERCP plus transpapillary stenting results in resolution of majority of pediatric PA/PPE. Children presenting with PA/PPE needs to be evaluated for CP.

Disconnected pancreatic duct syndrome: Updated review on clinical implications and management

Disconnected Pancreatic Duct Syndrome (DPDS) is an important but often overlooked complication of acute necrotising pancreatitis (ANP) that occurs due to necrosis of the main pancreatic duct (PD). This segmental necrosis leads on to disconnection between the viable upstream pancreatic parenchyma and the duodenum. The disconnected and functional segment of pancreas continues to secrete pancreatic juice that is not drained into the gastrointestinal tract and lead on to recurrent pancreatic fluid collections (PFC), refractory external pancreatic flstulae and chronic abdominal pain/recurrent pancreatitis. Because of lack of awareness of this important complication of ANP, the diagnosis of DPDS is usually delayed. The delay in diagnosis increases the morbidity of the disease as well as increase the cost of treatment and duration of hospital stay. Surgery has remained the cornerstone for management of patients with DPDS. The conventional surgical approaches have been either resection or internal drainage procedures. Surgery for DPDS in the setting of ANP is often difficult due to presence of local inflammation and extensive venous collaterals in the operative field due to splenic vein thrombosis and therefore is associated with significant morbidity. Advancement in therapeutic endoscopy, especially advent of therapeutic endoscopic ultrasound has opened an exciting new field of minimally invasive therapeutic options for management of DPDS. The present review discusses the current understanding of the clinical manifestations, imaging features and management strategies in patients with DPDS.

MRI in acute pancreatitis

Computed tomography (CT) is the most commonly performed imaging test for acute pancreatitis. Nevertheless, magnetic resonance (MRI) imaging is useful in many specific situations. These include evaluating patients with acute pancreatitis who cannot receive iodinated CT contrast, elucidating the underlying cause of acute pancreatitis, assessing ductal disconnection and for guiding intervention of necrotic collections. Non-contrast MRI is superior to non-contrast CT and MRI for the diagnosis of acute pancreatitis. We discuss these specific uses of MRI in acute pancreatitis. We highlight the future advances in MRI including faster, free-breathing scans that allow MRI to be completed within 10 min.

Traumatic pancreatitis

Post-traumatic pancreatitis can develop secondary to blunt or penetrating abdominal trauma, post-endoscopic retrograde cholangiopancreatography, or following pancreatic surgery. Clinical findings are often nonspecific, and imaging findings can be subtle on presentation. Early diagnosis of pancreatic duct injury is critical and informs management strategy; imaging plays important role in diagnosis of ductal injury and identification of delayed complications such as retroperitoneal fluid collections, pancreatic fistula, ductal strictures, and recurrent pancreatitis. Delayed diagnosis of pancreatic injury is associated with high mortality and morbidity, and therefore, heightened clinical suspicion is important in order for the radiologist to effectively impact patient care. There are accepted scoring systems for classification of post-traumatic pancreatic injuries and these should be included in radiology reports. Pancreatitis following ERCP appears similar on imaging to other causes of acute pancreatitis unless concomitant perforation occurs. Postoperative pancreatitis may be difficult to diagnose given associated or overlapping expected postoperative findings. Postoperative pancreatic fistulas typically arise from either a leaking pancreatic resection surface or the pancreatoenteric anastomosis and are more common in patients with a "soft" pancreas. Preoperative imaging biomarkers like duct diameter, pancreatic glandular steatosis and parenchymal fibrosis can help predict risk of development of postoperative pancreatic fistula. This review will illustrate the imaging features and the most important imaging findings in patients with post-traumatic pancreatitis.

Immune Checkpoint Inhibitor-Induced Pancreatic Injury: Imaging Findings and Literature Review

The immunotherapy revolution in cancer treatment involves a variety of specialists, not only oncologists, but also internal medicine physicians, endocrinologists, dermatologists, gastroenterologists, rheumatologists, and radiologists, introducing new scenarios and novel challenges in the diagnosis and management of a number of novel immune-related adverse events. Among these, immune checkpoint inhibitor-induced pancreatic injury has been described (occurring in up to 4% of patients) and has been reported to be responsible for visits to the emergency departments in up to 1.9% of patients treated with immune checkpoint inhibitors. This side effect can be symptomatic or non-symptomatic, and can be associated with the development of long-term damage to the pancreas, requiring the involvement of different specialists, including radiologists and gastroenterologists in the multidisciplinary team that manages these patients. The aim of this narrative review is to provide a summary of the available literature related to immune checkpoint inhibitor-induced pancreatic injury including the epidemiology, the clinical findings, and the management algorithm for diagnosis with a detailed analysis of the differential diagnosis at imaging, and treatment. A more in-depth focus is dedicated to symptomatic acute pancreatitis with its peculiar findings at imaging (ultrasound, computed tomography, and magnetic resonance imaging).

Treatment of disrupted and disconnected pancreatic duct in necrotizing pancreatitis: A systematic review and meta-analysis

BACKGROUND

Necrotizing pancreatitis may lead to loss of integrity of the pancreatic duct, resulting in leakage of pancreatic fluid. Pancreatic duct disruption or disconnection is associated with a prolonged disease course and particular complications. Since a standard treatment for this condition is currently lacking, we performed a systematic review of the literature to compare outcomes of various treatment strategies.

METHODS

A systematic review was performed according to the PRISMA guidelines in the PubMed, EMBASE and Cochrane databases. Included were articles considering the treatment of patients with disrupted or disconnected pancreatic duct resulting from acute necrotizing pancreatitis.

RESULTS

Overall, 21 observational cohort studies were included comprising a total of 583 relevant patients. The most frequently used treatment strategies included endoscopic transpapillary drainage, endoscopic transluminal drainage, surgical drainage or resection, or combined procedures. Pooled analysis showed success rates of 81% (95%-CI: 60-92%) for transpapillary and 92% (95%-CI: 77-98%) for transluminal drainage, 80% (95%-CI: 67-89%) for distal pancreatectomy and 84% (95%-CI: 73-91%) for cyst-jejunostomy. Success rates did not differ between surgical procedures (cyst-jejunostomy and distal pancreatectomy (risk ratio = 1.06, p = .26)) but distal pancreatectomy was associated with a higher incidence of endocrine pancreatic insufficiency (risk ratio = 3.06, p = .01). The success rate of conservative treatment is unknown.

DISCUSSION

Different treatment strategies for pancreatic duct disruption and duct disconnection after necrotizing pancreatitis show high success rates but various sources of bias in the available studies are likely. High-quality prospective, studies, including unselected patients, are needed to establish the most effective treatment in specific subgroups of patients, including timing of treatment and long-term follow-up.

Endoscopic Ultrasound-Guided Rendezvous Procedure for a Nondilated, Leaking Pancreatic Duct

Pancreatic duct (PD) leak leading to pancreatic ascites is a serious complication of chronic pancreatitis. Endoscopic management with endoscopic retrograde cholangiopancreatography (ERCP) has been found to be successful; however, if selective cannulation of the PD is unsuccessful, an endoscopic ultrasound–guided rendezvous procedure can help in bridging PD leaks, provided the duct is dilated. We report a successful endoscopic ultrasound–guided rendezvous procedure in a patient with PD leak, pancreatic ascites, and a nondilated duct with failed ERCP who was a poor candidate for surgery. The pancreatic ascites resolved following the procedure.

Endoscopic management of complications of acute pancreatitis: an update on the field

INTRODUCTION

Acute pancreatitis is a frequent, nonmalignant gastrointestinal disorder leading to hospital admission. For its severe form and subsequent complications, minimally invasive and endoscopic procedures are being used increasingly, and are subject to rapid technical advances. Areas covered: Based on a systematic literature search in PubMed, medline, and Web-of-Science, we discuss the currently available treatment strategies for endoscopic therapy of pancreatic pseudocysts, walled-off pancreatic necrosis (WON), and disconnected pancreatic duct syndrome (DPDS), and compare the efficacy and safety of plastic and metal stents. A special focus is placed on studies directly comparing different stent types, including lumen-apposing metal stents (LAMS) and clinical outcomes when draining pseudocysts or WONs. The clinical significance and endoscopic treatment options for DPDS are also discussed. Expert commentary: Endoscopic therapy has become the treatment of choice for different types of pancreatic and peripancreatic collections, the majority of which, however, require no intervention. The use of LAMS has facilitated drainage and necrosectomy in patients with WON or pseudocysts. Serious complications remain a problem in spite of high technical and clinical success rates. DPDS is an increasingly recognized problem in the presence of pseudocysts or WONs but evidence for endoscopic stent placement in this situation remains insufficient.

Comparison of diagnostic imaging modalities for the evaluation of pancreatic duct injury in children: a multi-institutional analysis from the Pancreatic Trauma Study Group

PURPOSE

Determining the integrity of the pancreatic duct is important in high-grade pancreatic trauma to guide decision making for operative vs non-operative management. Computed tomography (CT) is generally an inadequate study for this purpose, and magnetic resonance cholangiopancreatography (MRCP) is sometimes obtained to gain additional information regarding the duct. The purpose of this multi-institutional study was to directly compare the results from CT and MRCP for evaluating pancreatic duct disruption in children with these rare injuries.

METHODS

Retrospective study of data obtained from eleven pediatric trauma centers from 2010 to 2015. Children up to age 18 with suspected blunt pancreatic duct injury who had both CT and MRCP within 1 week of injury were included. Imaging findings of both studies were directly compared and analyzed using descriptive statistics, Chi square, Wilcoxon rank-sum, and McNemar's tests.

RESULTS

Data were collected for 21 patients (mean age 7.8 years). The duct was visualized more often on MRCP than CT (48 vs 5%, p < 0.05). Duct disruption was confirmed more often on MRCP than CT (24 vs 0%), suspected based on secondary findings equally (38 vs 38%), and more often indeterminate on CT (62 vs 38%). Overall, MRCP was not superior to CT for determining duct integrity (62 vs 38%, p = 0.28).

CONCLUSIONS

In children with blunt pancreatic injury, MRCP is more useful than CT for identifying the pancreatic duct but may not be superior for confirmation of duct integrity. Endoscopic retrograde cholangiogram (ERCP) may be necessary to confirm duct disruption when considering pancreatic resection.

LEVEL OF EVIDENCE

III.

Endoscopic Management of Infected Necrotizing Pancreatitis: an Evidence-Based Approach

PURPOSE OF REVIEW

Endoscopic management of infected necrotizing pancreatitis has evolved rapidly over the past years and there have been interesting innovations in this field. This review provides an update on the most recently published literature regarding endoscopic management of infected necrotizing pancreatitis.

RECENT FINDINGS

A recent randomized trial demonstrated no difference in mortality and major morbidity between endoscopic and surgical step-up treatment of infected necrotizing pancreatitis. However, endoscopic therapy resulted in shorter hospital stay and less pancreatic fistulas. Various innovations have been investigated with the aim to further optimize endoscopic therapy, in particular lumen-apposing metal stents. While major stent-related complications were also reported, findings from recent studies indicated that their use was associated with higher resolution rates of walled-off necrosis compared to double-pigtail stents. Other innovations, such as the multiple gateway technique and dual-modality mode, can be considered for treatment of particular cases. Furthermore, research suggests that irrigation of walled-off necrosis can be performed by using a nasocystic tube and discontinuation of proton-pump inhibitors may be considered. Endoscopic treatment should be the preferred treatment modality in patients with infected necrotizing pancreatitis who are eligible for endoscopic drainage. Although data suggests that lumen-apposing metal stents are superior to double-pigtail stents, prospective multicenter studies focusing on safety as well as long-term follow-up are first needed.

Specialized Imaging and Procedures in Pediatric Pancreatology: A North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition Clinical Report

OBJECTIVES

An increasing number of children are being diagnosed with pancreatitis and other pancreatic abnormalities. Dissemination of the information regarding existing imaging techniques and endoscopic modalities to diagnose and manage pancreatic disorders in children is sorely needed.

METHODS

We conducted a review of the medical literature on the use of the following imaging and procedural modalities in pediatric pancreatology: transabdominal ultrasonography (TUS), computed tomography (CT), magnetic resonance imaging (MRI)/magnetic resonance cholangiopancreatography (MRCP), endoscopic ultrasonography (EUS), and endoscopic retrograde cholangiopancreatography (ERCP). Recommendations for current use and future research were identified.

RESULTS

TUS offers noninvasive images of the pancreas but has limitations to details of parenchyma and ductal structures. CT offers improved detail of pancreatic parenchyma, solid masses, and traumatic injuries, but requires relatively high levels of ionizing radiation and does not adequately assess ductal anatomy. MRI/MRCP offers detailed intrinsic tissue assessment and pancreatic ductal characterization, but requires longer image acquisition time and is relatively poor at imaging calcifications. EUS provides excellent evaluation of pancreatic parenchyma and ductal anatomy, but can be subjective and operator dependent and requires sedation or anesthesia. EUS offers the capacity to obtain tissue samples and drain fluid collections and ERCP offers the ability to improve drainage by performing sphincterotomy or placing pancreatic stents across duct injuries and strictures.

CONCLUSIONS

Various imaging modalities may be used in pediatric pancreatology, but TUS and MRI/MRCP are favored. Interventional therapeutic maneuvers primarily involve use of ERCP and EUS. Future research is necessary to optimize equipment, expertise, and appropriate indications.

Acute Pancreatitis in Pediatric Patients: Demographics, Etiology, and Diagnostic Imaging

OBJECTIVE

The objective of this article is to provide updates on acute pancreatitis in children regarding the imaging findings, causes, and complications based on a review of the current studies in the pediatrics literature. We discuss the epidemiology of acute pancreatitis, the role of imaging and imaging findings in the diagnosis of acute pancreatitis, and the causes and complications of acute pancreatitis.

CONCLUSION

The incidence of acute pancreatitis is increasing in children. Imaging plays an important role in the diagnosis of acute pancreatitis because imaging findings can be used to establish the cause of acute pancreatitis, evaluate for complications of acute pancreatitis, and possibly predict the course of the disease.

Magnetic resonance imaging of retroperitoneal interfascial plane involvement in acute pancreatitis

BACKGROUND

To study the magnetic resonance imaging (MRI) features of acute pancreatitis (AP) involving the retroperitoneal interfascial planes and to analyze the correlations of interfascial plane involvement with the magnetic resonance severity index (MRSI) and the Acute Physiology and Chronic Health Evaluation (APACHE II) scoring system.

METHODS

A total of 316 consecutive patients with AP between November 2011 and August 2013 were retrospectively analyzed. The extension and path of the inflammation spreading along the retroperitoneal interfascial plane on MRI were graded from grade 0 to grade 5. The relationships between interfascial plane involvement and MRSI and APACHE II were analyzed.

RESULTS

Of the 316 patients with AP, 293 patients (92.7%) had interfascial plane involvement, which appeared as interfascial plane edema, thickening and effusion. There were 60, 105, 78, 25, and 25 patients in grades 1, 2, 3, 4, and 5, respectively. Interfascial plane involvement strongly correlated with the MRSI score (r=0.703), but was only weakly correlated with the APACHE-II score (r=0.291).

CONCLUSIONS

MRI depicts the characteristics of interfascial plane involvement in AP. The value of interfascial plane involvement for determining the disease severity is likely to be limited.

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

PURPOSE

Compare CT and MRI for fluid/debris component estimate and pancreatic duct (PD) communication with organized pancreatic fluid collections in acute pancreatitis. Evaluate fat density globules on CT as marker for debris.

METHODS

29 Patients with 46 collections with CECT and MRI performed ≥4 weeks of symptom onset assessed for necrotizing pancreatitis, estimated percentage of fluid volume and PD involvement by two radiologists on separate occasions. T2WI used as standard for estimated percentage of fluid volume. Presence of fat globules and fluid attenuation on CT was recorded. Spearman rank correlation and kappa statistics were used to assess the correlation between imaging techniques and interreader agreement, respectively.

RESULTS

Necrotizing pancreatitis seen on CT in 27 (93%, κ 0.119) vs. 20 (69%, κ 0.748) patients on MRI. CT identified 42 WON and 4 pseudocysts vs. 34 WON, and 12 pseudocysts on MRI. Higher interreader agreement for percentage fluid volume on MRI (κ = 0.55) vs. CT (κ = 0.196). Accuracy of CT in evaluation of percentage fluid volume was 65% using T2WI MRI used as standard. Fat globules identified on CT in 13(65%) out of 20 collections containing <75% fluid vs. 4(15%) out of 26 collections containing >75% fluid (p = 0.0001). PD involvement confidently excluded on CT in 68% collections vs. 93% on MRI.

CONCLUSION

MRI demonstrates higher reproducibility for fluid to debris component estimation. Fat globules on CT were frequently seen in organized pancreatic fluid collections with large amount of debris. PD disruption more confidently excluded on MRI. This information may be helpful for pre-procedure planning.

Early endoscopic treatment of blunt traumatic pancreatic injury

Blunt pancreatic trauma is a rare and challenging situation. In many cases, there are other associated injuries that mandate urgent operative treatment. Morbidity and mortality rates are high and complications after acute pancreatic resections are common. The diagnosis of pancreatic injuries can be difficult and often requires multimodal approach including Computed Tomography scans, Magnetic resonance imaging and Endoscopic retrograde cholangiopancreaticography (ERCP). The objective of this paper is to review the application of endoprothesis in the settings of pancreatic injury. A review of the English literature available was conducted and the experience of our centre described. While the classical recommended treatment of Grade III pancreatic injury (transection of the gland and the pancreatic duct in the body/tail) is surgical resection this approach carries high morbidity. ERCP was first reported as a diagnostic tool in the settings of pancreatic injury but has in recent years been used increasingly as a treatment option with promising results. This article reviews the literature on ERCP as treatment option for pancreatic injury and adds further to the limited number of cases reported that have been treated early after the trauma.

Pancreatic fluid collections: What is the ideal imaging technique?

Pancreatic fluid collections (PFCs) are seen in up to 50% of cases of acute pancreatitis. The Revised Atlanta classification categorized these collections on the basis of duration of disease and contents, whether liquid alone or a mixture of fluid and necrotic debris. Management of these different types of collections differs because of the variable quantity of debris; while patients with pseudocysts can be drained by straight-forward stent placement, walled-off necrosis requires multi-disciplinary approach. Differentiating these collections on the basis of clinical severity alone is not reliable, so imaging is primarily performed. Contrast-enhanced computed tomography is the commonly used modality for the diagnosis and assessment of proportion of solid contents in PFCs; however with certain limitations such as use of iodinated contrast material especially in renal failure patients and radiation exposure. Magnetic resonance imaging (MRI) performs better than computed tomography (CT) in characterization of pancreatic/peripancreatic fluid collections especially for quantification of solid debris and fat necrosis (seen as fat density globules), and is an alternative in those situations where CT is contraindicated. Also magnetic resonance cholangiopancreatography is highly sensitive for detecting pancreatic duct disruption and choledocholithiasis. Endoscopic ultrasound is an evolving technique with higher reproducibility for fluid-to-debris component estimation with the added advantage of being a single stage procedure for both diagnosis (solid debris delineation) and management (drainage of collection) in the same sitting. Recently role of diffusion weighted MRI and positron emission tomography/CT with (18)F-FDG labeled autologous leukocytes is also emerging for detection of infection noninvasively. Comparative studies between these imaging modalities are still limited. However we look forward to a time when this gap in literature will be fulfilled.

Magnetic resonance imaging of pancreatitis: An update

Magnetic resonance (MR) imaging plays an important role in the diagnosis and staging of acute and chronic pancreatitis and may represent the best imaging technique in the setting of pancreatitis due to its unmatched soft tissue contrast resolution as well as non-ionizing nature and higher safety profile of intravascular contrast media, making it particularly valuable in radiosensitive populations such as pregnant patients, and patients with recurrent pancreatitis requiring multiple follow-up examinations. Additional advantages include the ability to detect early forms of chronic pancreatitis and to better differentiate adenocarcinoma from focal chronic pancreatitis. This review addresses new trends in clinical pancreatic MR imaging emphasizing its role in imaging all types of acute and chronic pancreatitis, pancreatitis complications and other important differential diagnoses that mimic pancreatitis.

Pancreatitis-imaging approach

Pancreatitis is defined as the inflammation of the pancreas and considered the most common pancreatic disease in children and adults. Imaging plays a significant role in the diagnosis, severity assessment, recognition of complications and guiding therapeutic interventions. In the setting of pancreatitis, wider availability and good image quality make multi-detector contrast-enhanced computed tomography (MD-CECT) the most used imaging technique. However, magnetic resonance imaging (MRI) offers diagnostic capabilities similar to those of CT, with additional intrinsic advantages including lack of ionizing radiation and exquisite soft tissue characterization. This article reviews the proposed definitions of revised Atlanta classification for acute pancreatitis, illustrates a wide range of morphologic pancreatic parenchymal and associated peripancreatic changes for different types of acute pancreatitis. It also describes the spectrum of early and late chronic pancreatitis imaging findings and illustrates some of the less common types of chronic pancreatitis, with special emphasis on the role of CT and MRI.

Endoscopic therapy for pancreatic duct leaks and disruptions

Pancreatitis, whether acute or chronic, can lead to a plethora of complications, such as fluid collections, pseudocysts, fistulas, and necrosis, all of which are secondary to leakage of secretions from the pancreatic ductal system. Partial and side branch duct disruptions can be managed successfully by transpapillary pancreatic duct stent placement, whereas patients with disconnected pancreatic duct syndrome require more complex endoscopic interventions or multidisciplinary care for optimal treatment outcomes. This review discusses the current status of endoscopic management of pancreatic duct leaks and emerging concepts for the treatment of disconnected pancreatic duct syndrome.

Pancreatic duct patterns in acute pancreatitis: a MRI study

OBJECTIVES

To study the MRI findings of the pancreatic duct in patients with acute pancreatitis.

MATERIALS AND METHODS

A total of 239 patients with acute pancreatitis and 125 controls were analyzed in this study. The severity of acute pancreatitis was graded using the MR severity index (MRSI) and the Acute Physiology And Chronic Healthy Evaluation II(APACHE II) scoring systems. The number of main pancreatic duct (MPD) segments visualized, and both MPD diameter and pancreatic duct disruption were noted and compared with the severity of acute pancreatitis.

RESULTS

The frequency of MPD segment visualization in the control group was higher than that in the acute pancreatitis group (p<0.05). The number of MPD segments visualized was negatively correlated with the MRSI score (p<0.05) and the APACHE II score (p<0.05). There was no difference in the MPD diameter between the acute pancreatitis and control groups or among the patients with different severities of acute pancreatitis (p>0.05). The prevalence of pancreatic duct disruption was 7.9% in the acute pancreatitis group. The prevalences of pancreatic duct disruption were 4.8% and 15.3% in the mild and severe acute pancreatitis groups based on the APACHE II score, respectively, and were 0%, 5.7% and 43.5% in the mild, moderate and severe acute pancreatitis groups according the MRSI score, respectively. The prevalence of pancreatic duct disruption was correlated with the severity of acute pancreatitis based on the APACHE II score (p<0.05) and MRSI score (p<0.05).

CONCLUSION

The pancreatic duct in acute pancreatitis patients was of normal diameter. The number of MPD segments visualized and visible pancreatic duct disruption on MRI may be supplementary indicators for determining the severity of acute pancreatitis.