Pancreatic fluid collections: What is the ideal imaging technique?

Management of acute pancreatitis in the "no man's land"

Acute pancreatitis (AP) is an inflammatory disease that can represent a challenge for clinicians, in fact, the early determination of its severity in the first 72 h is crucial for prognosis, recognizing the etiology and carrying out risk stratification to determine a more specific therapy. No accurate early prognostic scores for disease severity have been published, so the severity of AP often cannot be properly defined in the first few hours of the disease. This initial phase represents a "no man's land", in which there is no certainty in the stratification of the damage, prognosis is difficult to establish, therapy must be started promptly, although there is still no effective medical therapy against pancreatic enzymatic activation. Therefore, it is very difficult at this stage to make the correct decisions to achieve the best outcome for the patient with AP. Literature search was carried out using the PubMed database by entering early management of acute pancreatitis [title] or therapy of acute pancreatitis [title] and selecting the most relevant articles for the diagnosis and therapy of acute pancreatitis in clinical practice. This document provides suggestions on managing the key clinical decisions for patients suffering from AP before disease severity is defined, to achieve the best outcomes for patients with AP.

Practical management of severe acute pancreatitis

Acute pancreatitis (AP) represents one of the most common reasons for hospital admission and intensive care treatment in internal medicine. The incidence of AP is increasing, posing significant financial burden on healthcare systems due to the necessity for frequent medical interventions. Severe acute pancreatitis (SAP) is a potentially life-threatening condition with substantial morbidity and mortality. The management of SAP requires prolonged hospitalization and the expertise of a multidisciplinary team, comprising emergency physicians, intensivists, internists, gastroenterologists, visceral surgeons, and experts in nutrition, infectious disease, endoscopy, as well as diagnostic and interventional radiology. Effective management and beneficial patient outcomes depend on continuous interdisciplinary collaboration. This review synthesizes recent evidence guiding the practical management of SAP, with a particular focus on emergency and intensive care settings. Both established as well as new diagnostic and therapeutic paradigms are highlighted, including workup, risk stratification, fluid management, analgesia, nutrition, organ support, imaging modalities and their timing, along with anti-infective strategies. Furthermore, the review explores interventions for local and vascular complications of SAP, with particular attention to the indications, timing and selection between endoscopic (both endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS)), percutaneous and surgical approaches. Similarly, the management of biliary AP due to obstructive gallstones, including the imaging, timing of ERCP and cholecystectomy, are discussed. By integrating new evidence with relevant guidance for everyday clinical practice, this review aims to enhance the interdisciplinary approach essential for improving outcomes in SAP management.

Surgical Step-Up Approach in Management of Necrotizing Pancreatitis

Necrotizing pancreatitis often demands intervention; contemporary management is directed by the step-up approach. Timing of intervention and specific approach is best directed by a multi-disciplinary team including advanced endosocpists, interventional radiologists, and surgeons with interest and experience managing this complex problem. The intervention is often a combination of percutaneous drainage, transluminal endoscopic approaches, and surgical debridement (minimally invasive or open). Goals of treatment are to evacuate solid infected necrosis, gain enteral access when needed, and to prevent recurrence-cholecystectomy in the setting of biliary pancreatitis. Experienced clinical judgment leads to optimal patient outcomes.

Pancreatic Cystic Lesions in Children: A Comprehensive Scoping Review

OBJECTIVE

Pediatric pancreatic cystic lesions (PPCLs) are uncommon and differ from adult pancreatic cystic lesions. Literature is limited on the etiologies, evaluation, and management of PPCL. A multidisciplinary working group formed to provide a comprehensive description of PPCL and recommend best available evidence-based evaluation and management.

MATERIALS AND METHODS

The PPCL working group performed a scoping review by 2 methods: 1) a targeted literature review to describe PPCL and 2) a systematic literature review for management recommendations for PPCL. The systematic review was completed using a 2-stage sifting approach: title and abstract screening followed by a full text review.

RESULTS

One hundred thirty-one studies were included in the systematic review and an additional 20 were included in the targeted search to complete a comprehensive list of PPCL. Five neoplastic PPCL and 10 nonneoplastic PPCL were identified, and prevalence of different cystic lesions differs widely in adults and children. Recommendations on evaluation and management of PPCL are presented based on best available evidence.

CONCLUSIONS

We present a comprehensive review and evidence-based management recommendations with management algorithms for pediatric pancreatic cystic lesions. Given the rarity of many of these entities, this review also highlights many aspects of PPCL, which are not adequately described in the current literature.

Thirty-day prevalence and clinical impact of fluid collections at the resection margin after distal pancreatectomy: Follow-up of a multicentric randomized controlled trial

BACKGROUND

Postoperative fluid collections at the resection margin of the pancreatic stump are frequent after distal pancreatectomy, yet their clinical impact is unclear. The aim of this study was to assess the 30-day prevalence of postoperative fluid collections after distal pancreatectomy and the factors associated with a clinically relevant condition.

METHODS

Patients enrolled in a randomized controlled trial of parenchymal transection with either reinforced, triple-row staple, or ultrasonic dissector underwent routine magnetic resonance 30 days postoperatively. Postoperative fluid collection was defined as a cyst-like lesion of at least 1 cm at the pancreatic resection margin. Postoperative fluid collections requiring any therapy were defined as clinically relevant.

RESULTS

A total of 133 patients were analyzed; 69 were in the triple-row staple transection arm, and 64 were in the ultrasonic dissector transection arm. The overall 30-day prevalence of postoperative fluid collections was 68% (n = 90), without any significant difference between the two trial arms. Postoperative serum hyperamylasemia was more frequent in patients with postoperative fluid collections than those without (31% vs 7%, P = .001). Among the postoperative fluid collection population, an early postoperative pancreatic fistula (odds ratio 14.9, P = .002), post pancreatectomy acute pancreatitis (odds ratio 12.7, P = .036), and postoperative fluid collection size larger than 50 mm (odds ratio 6.6, P = .046) were independently associated with a clinically relevant postoperative fluid collection.

CONCLUSION

Postoperative fluid collections at the resection margin are common after distal pancreatectomy and can be predicted by early assessment of postoperative serum hyperamylasemia. A preceding pancreatectomy acute pancreatitis and/or postoperative pancreatic fistula and large collections (>50 mm) were associated with a clinically relevant postoperative fluid collection, representing targets for closer follow-up or earlier therapeutic interventions.

Cross-sectional imaging after pancreatic surgery: The dialogue between the radiologist and the surgeon

Pancreatic surgery is nowadays considered one of the most complex surgical approaches and not unscathed from complications. After the surgical procedure, cross-sectional imaging is considered the non-invasive reference standard to detect early and late compilations, and consequently to address patients to the best management possible. Contras-enhanced computed tomography (CECT) should be considered the most important and useful imaging technique to evaluate the surgical site. Thanks to its speed, contrast, and spatial resolution, it can help reach the final diagnosis with high accuracy. On the other hand, magnetic resonance imaging (MRI) should be considered as a second-line imaging approach, especially for the evaluation of biliary findings and late complications. In both cases, the radiologist should be aware of protocols and what to look at, to create a robust dialogue with the surgeon and outline a fitted treatment for each patient.

Risk Factors Associated With the Development of Acute Peripancreatic Fluid Collections on Follow-Up Imaging After Acute Pancreatitis: What Physicians Need to Know

OBJECTIVES

This study aims to identify various risk factors for acute peripancreatic fluid collections (APFCs) in patients presenting with acute pancreatitis (AP).

METHODS

A blinded retrospective case-control study was conducted at a tertiary care hospital in Riyadh. Data from 327 patients who presented with AP between January 2008 and 2021 were analyzed. Following the application of inclusion/exclusion criteria, the final sample size consisted of 82 patients. Patients were divided into cases and controls based on the presence or absence of APFCs, respectively. APFCs were defined as fluid collections in the peripancreatic region that develop within four weeks of presentation without well-defined walls or solid internal components. Demographic, clinical, and laboratory variables were collected and subjected to multivariate binary regression analysis to assess the odds of developing APFCs.

RESULTS

A total of 34 patients were categorized as cases, while 48 patients were controls. A significant association was found between age (P=0.022), total bilirubin (P=0.012), lipase level (P<0.001), albumin level (P=0.038), and lactate dehydrogenase (LDH) (P=0.037) on admission and the odds of developing APFCs.

CONCLUSION

Older age, higher levels of bilirubin and lipase, and low levels of albumin and LDH were found to be risk factors for developing APFCs. No other variables were found to be significant. The findings of this study may provide insight into how often clinicians can expect APFCs in patients presenting with AP.

Acute pancreatitis: A review of diagnosis, severity prediction and prognosis assessment from imaging technology, scoring system and artificial intelligence

Acute pancreatitis (AP) is a potentially life-threatening inflammatory disease of the pancreas, with clinical management determined by the severity of the disease. Diagnosis, severity prediction, and prognosis assessment of AP typically involve the use of imaging technologies, such as computed tomography, magnetic resonance imaging, and ultrasound, and scoring systems, including Ranson, Acute Physiology and Chronic Health Evaluation II, and Bedside Index for Severity in AP scores. Computed tomography is considered the gold standard imaging modality for AP due to its high sensitivity and specificity, while magnetic resonance imaging and ultrasound can provide additional information on biliary obstruction and vascular complications. Scoring systems utilize clinical and laboratory parameters to classify AP patients into mild, moderate, or severe categories, guiding treatment decisions, such as intensive care unit admission, early enteral feeding, and antibiotic use. Despite the central role of imaging technologies and scoring systems in AP management, these methods have limitations in terms of accuracy, reproducibility, practicality and economics. Recent advancements of artificial intelligence (AI) provide new opportunities to enhance their performance by analyzing vast amounts of clinical and imaging data. AI algorithms can analyze large amounts of clinical and imaging data, identify scoring system patterns, and predict the clinical course of disease. AI-based models have shown promising results in predicting the severity and mortality of AP, but further validation and standardization are required before widespread clinical application. In addition, understanding the correlation between these three technologies will aid in developing new methods that can accurately, sensitively, and specifically be used in the diagnosis, severity prediction, and prognosis assessment of AP through complementary advantages.

Acute peripancreatic fluid collection in acute pancreatitis: Incidence, outcome, and association with inflammatory markers

Background

The hospital outcomes and predictors of acute peripancreatic fluid collection (APFC) have not been well-characterized. In this study, we aimed to investigate the clinical outcomes of APFC in patients with acute pancreatitis (AP) and the role of the systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), and C-reactive protein (CRP) level in predicting the occurrence of APFC.

Methods

In this retrospective study, the complicated group (patients with APFC) and the uncomplicated group (patients without APFC) were compared for their clinical characteristics, hospital outcomes (mortality rate, intensive care unit admission rate, and length of hospital stay), pseudocyst formation, CRP levels, SII, and SIRI on admission and at 48 hours.

Results

Of 132 patients with AP, 51 (38.6%) had APFC and eight (6.1%) had pancreatic pseudocysts. Of 51 patients with APFC, 15.7% had pancreatic pseudocysts. Pseudocyst did not develop in the uncomplicated group. SII value at 48 h [median 859 (541-1740) x 109/L vs. 610 (343-1259) x 109/L, P = 0.01] and CRP level at 48 h [89 (40-237) mg/L vs. 38 (12-122) mg/L, P = 0.01] were higher in the complicated group than in the uncomplicated group. The length of hospital stay was longer in the complicated group, compared with the uncomplicated group [median 8 days (5-15), vs. 4 days (3-7), P < 0.001, respectively]. No significant difference was detected between the two study groups' mortality rates and intensive care unit admission rates.

Conclusions

While 38.6% of the AP patients had APFC, 6.1% of all patients and 15.7% of the patients with APFC had pancreatic pseudocysts. APFC was found to lengthen the hospital stay and to be associated with the SII value and CRP level measured at 48 h.

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.

Incidence of peripancreatic fluid collections in patients presenting with acute pancreatitis

OBJECTIVES

To calculate the incidence of acute peripancreatic fluid collection (APFC) in patients with acute pancreatitis. The secondary objective is to determine the underlying etiologies of acute pancreatitis in the Saudi population.

METHODS

A retrospective cohort study was carried out at King Khalid University Hospital, King Saud University, Riyadh, Saudi Arabia. The study analyzed data from patients who were diagnosed with acute pancreatitis between January 2008 and January 202. A total of 327 were included in the study after applying the inclusion and exclusion criteria. Their medical records were subsequently reviewed for the presence or absence of APFC on follow-up imaging studies, evidence of biliary stones, prior endoscopic retrograde cholangiopancreatography (ERCP), a history of alcohol use, and demographic variables.

RESULTS

Of the 327 patients with acute pancreatitis, 158 (48.3%) developed APFC, while 169 (51.7%) did not. The majority of patients had an idiopathic etiology of acute pancreatitis (n=251; 76.8%); followed by a biliary etiology (n=51; 15.6%); post-ERCP complications (n=14; 4.3%), and other causes (n=11; 3.3%).

CONCLUSION

The incidence of APFC in patients presenting with acute pancreatitis between January 2008 and January 2021 was 48.3%. The most common etiology of acute pancreatitis in this tertiary care hospital was idiopathic, followed by biliary etiologies and post-ERCP complications. More studies targeting the local complications of pancreatitis are needed to reach more definitive findings.

Management of Necrotizing Pancreatitis

Necrotizing pancreatitis affects 10% to 15% of all patients with acute pancreatitis. Despite improved understanding of this complex disease, it is still attended by up to 15% mortality. Necrotizing pancreatitis provides the clinical challenges of working in a multi-disciplinary group, determining proper timing for intervention, and identifying appropriate intervention approaches. The step-up approach consists of supportive care initially. When there is documented infected necrosis, treatment begins with antibiotics, progressing to minimally invasive mechanical necrosis intervention, and reserving surgery as the final treatment modality. However, treatment must be tailored to the individual patient. This article provides an overview of necrotizing pancreatitis.

A new logistic regression model for early prediction of severity of acute pancreatitis using magnetic resonance imaging and Acute Physiology and Chronic Health Evaluation II scoring systems

BACKGROUND

The aim of this study was to develop a new model constructed by logistic regression for the early prediction of the severity of acute pancreatitis (AP) using magnetic resonance imaging (MRI) and the Acute Physiology and Chronic Health Evaluation II (APACHE II) scoring system.

METHODS

This retrospective study included 363 patients with AP. The severity of AP was evaluated by MRI and the APACHE II scoring system, and some subgroups of AP severity were constructed based on a combination of these two scoring systems. The length of stay and occurrence of organ dysfunction were used as clinical outcome indicators and were compared across the different subgroups. We combined the MRI and APACHE II scoring system to construct the regression equations and evaluated the diagnostic efficacy of these models.

RESULTS

In the 363 patients, 144 (39.67%) had systemic inflammatory response syndrome (SIRS), 58 (15.98%) had organ failure, and 17 (4.68%) had severe AP. The AP subgroup with a high MRI score and a simultaneously high APACHE II score was more likely to develop SIRS and had a longer hospitalization. The model, which predicted the severity AP by combining extrapancreatic inflammation on magnetic resonance (EPIM) and APACHE II, was successful, with an area under the receiver operating characteristic (ROC) curve (AUC) of 0.912, which was higher than that of any single parameter. Other models that predicted SIRS complications by combining MRI parameters and APACHE II scores were also successful (all P<0.05), and these models based on EPIM and APACHE II scores were superior to other models in predicting outcome.

CONCLUSIONS

The combination of MRI and clinical scoring systems to assess the severity of AP is feasible, and these models may help to develop personalized treatment and management.

Direct Endoscopic Necrosectomy: Timing and Technique

Walled-off pancreatic necrosis (WOPN) is one of the local complications of acute pancreatitis (AP). Several interventional techniques have been developed over the last few years. The purpose of this narrative review is to explore such methodologies, with specific focus on endoscopic drainage and direct endoscopic necrosectomy (DEN), through evaluation of their indications and timing for intervention. Findings indicated how, after the introduction of lumen-apposing metal stents (LAMS), DEN is becoming the favorite technique to treat WOPN, especially when large solid debris or infection are present. Additionally, DEN is associated with a lower adverse events rate and hospital stay, and with improved clinical outcome.

Pancreatic Disorders of Pregnancy

The pancreas is an organ with both exocrine and endocrine functions that has a vital role in both digestion as well as glucose metabolism. Although pancreatic dysfunction and disorders are rare in pregnancy, they are becoming increasingly more common. Recognition of these disorders and understanding how they can affect pregnancy is imperative to allow for proper management. We provide an overview of the most common pancreatic disorders that are seen in pregnancy.

The role of imaging in acute pancreatitis

Acute pancreatitis is one of the most commonly encountered etiologies in the emergency setting, with a broad spectrum of findings that varies in severity from mild interstitial pancreas to severe forms with significant local and systemic complications that are associated with a substantial degree of morbidity and mortality. In this article the radiological aspect of the terminology and classification of acute pancreatitis are reviewed. The roles of ultrasound, computed tomography, and magnetic resonance imaging in the diagnosis and evaluation of acute pancreatitis and its complications are discussed. The authors present a practical image-rich guide, applying the revised Atlanta classification system, with the goal of facilitating radiologists to write a correct report, and reinforcing the radiologist’s role as a key member of a multidisciplinary team in treating patients with acute pancreatitis. Computed tomography is the most performed imaging test for acute pancreatitis. Nevertheless, MRI is useful in many specific situations, due to its superiority soft tissue contrast resolution and better assessment of biliary and pancreatic duct, for example in the ductal disconnection. The purpose if this article is to review recent advances in imaging acquisition and analytic techniques in the evaluation of AP.

Magnetic resonance severity index assessed by T1-weighted imaging for acute pancreatitis: correlation with clinical outcomes and grading of the revised Atlanta classification-a narrative review

Acute pancreatitis (AP) is a common disease that may involve pancreas and peripancreatic tissues with a prevalence of up to 50 per 100,000 individuals for year. The Atlanta classification was assessed for the first time in 1992 and modified in 2012 in order to describe morphological features of AP and its complications. AP can be morphologically distinguished in two main types: interstitial edematous pancreatitis (IEP) and necrotizing pancreatitis (NEP). This classification is very important because the presence of necrosis is directly linked to local or systemic complications, hospital stays and death. Magnetic resonance (MR) is very useful to characterize morphological features in AP and its abdominal complications. Particularly we would like to underline the diagnostic, staging and prognostic role of T1-weighted images with fat suppression that could be significant to assess many features of the AP inflammatory process and its complications (detection of the pancreatic contour, pancreatic necrosis, presence of haemorrhage). Signs of inflammatory and edema are instead observed by T1-weighted images. MR cholangiopancreatography (MRCP) is necessary to study the main pancreatic duct and the extrahepatic biliary tract and contrast-enhancement magnetic resonance imaging (MRI) allows to assess the extent of necrosis and vascular injuries.

Imaging acute pancreatitis

OBJECTIVES

Acute pancreatitis is common; the clinical course of this potentially severe condition varies widely. This paper aims to review the role of different imaging techniques in the management of acute pancreatitis, describe the main imaging findings for this entity, and explain the terms and criteria used to classify them.

CONCLUSIONS

Imaging techniques play a key role in the management of acute pancreatitis, from diagnosis and staging to identifying and treating complications, as well as in determining the underlying causes of the condition. For these reasons, radiologists should know the advantages and limitations of each imaging technique in the evaluation of acute pancreatitis, be familiar with the wide spectrum of imaging findings associated with it, and how to use the specific terminology derived from the Atlanta classification to ensure the standardization and quality of reports.

Hematochezia secondary to hemosuccus pancreaticus due to a pseudoaneurysm associated with a pancreatic pseudocyst

The patient had a history of recurrent acute necrotizing pancreatitis, chronic pancreatitis and a pancreatic pseudocyst with an associated pseudoaneurysm in the superior mesenteric artery. He presented mesogastric pain, nausea, 187 U/l amylase and 242 U/l lipase. A hemorrhagic appearance inside the pseudocyst and lumen of the common bile duct was seen on ultrasound.

GRUPUGE Perspective: Endoscopic Ultrasound-Guided Drainage of Peripancreatic Collections

Pancreatic and peripancreatic collections (PPC) are a known complication of acute pancreatitis. They are categorized into four types of collection: (1) acute peripancreatic fluid collection, (2) pseudocyst, (3) acute necrotic collection and (4) walled-off necrosis. Most PPC resolve spontaneously or are persistent but asymptomatic. Intervention is needed in a minority of patients with infected or symptomatic collection. Endoscopic ultrasound-guided transmural drainage is currently the first-line treatment option for PPC management. It has shown great technical and clinical success, similar to percutaneous or surgical approaches, but with lower morbidity and costs and better quality of life. In this review article, the GRUPUGE presents an updated perspective on the potential role of endoscopic ultrasound-guided drainage of peripancreatic collections, addressing the selection criteria and the technical issues of different techniques and analysing emerging data on their efficacy and safety.

MR Imaging of the Perihepatic Space

The perihepatic space is frequently involved in a spectrum of diseases, including intrahepatic lesions extending to the liver capsule and disease conditions involving adjacent organs extending to the perihepatic space or spreading thanks to the communication from intraperitoneal or extraperitoneal sites through the hepatic ligaments. Lesions resulting from the dissemination of peritoneal processes may also affect the perihepatic space. Here we discuss how to assess the perihepatic origin of a lesion and describe the magnetic resonance imaging (MRI) features of normal structures and fluids that may be abnormally located in the perihepatic space. We then review and illustrate the MRI findings present in cases of perihepatic infectious, tumor-related, and miscellaneous conditions. Finally, we highlight the value of MRI over computed tomography.

Pancreatic fluid collections: Clinical manifestations, diagnostic evaluation and management

Pancreatic fluid collections (PFC), including pancreatic pseudocysts and walled-off pancreatic necrosis, are a known complication of severe acute pancreatitis. A majority of the PFCs remain asymptomatic and resolve spontaneously. However, some PFCs persist and can become symptomatic. Persistent PFCs can also cause further complications such as the gastric outlet, intestinal, or biliary obstruction and infection. Surgical interventions are indicated for the drainage of symptomatic sterile and infected PFCs. Management of PFCs has evolved from a primarily surgical or percutaneous approach to a less invasive endoscopic approach. Endoscopic interventions are associated with improved outcomes with lesser chances of complications, faster recovery time, and lower healthcare utilization. Endoscopic ultrasound-guided drainage of PFCs using lumen-apposing metal stents has become the preferred approach for the management of symptomatic and complicated PFCs.

Management of pancreatic collections: an update

Pancreatic fluid collections frequently occur in the context of moderate and severe acute pancreatitis, and may also appear as a complication of chronic pancreatitis, pancreatic surgery or trauma. It is essential to adhere to the Atlanta classification nomenclature that subclassifies them into four categories (acute peripancreatic fluid collections, acute necrotic collections, pseudocysts, and walled-off necrosis) since it has an impact on prognosis and management. Pseudocysts and walled-off pancreatic necrosis are encapsulated pancreatic fluid collections characterized by a surrounding inflammatory wall, which typically develops three to four weeks after the onset of acute pancreatitis. Most pancreatic fluid collections resolve spontaneously and do not require intervention. However, when they become symptomatic or complicated drainage is indicated, and endoscopic ultrasound-guided drainage has become first-line treatment of encapsulated collections. Drainage of pseudocysts is relatively straightforward due to their liquid content. However, in walled-off necrosis the presence of solid necrotic debris can make treatment more challenging and therefore multidisciplinary management in experienced centers is recommended, being a step-up approach the current standard of care. In this review, we aim to address the management of pancreatic fluid collections with an especial focus on endoscopic drainage.

Current concepts for the diagnosis of acute pancreatitis by multiparametric magnetic resonance imaging

Acute pancreatitis is classically characterized by acute chemical inflammation of the pancreatic gland itself, peripancreatic tissues, and even remote organs. The newly revised Atlanta Classification 2012 redefined the patterns of pancreatic necrosis and local complications in acute pancreatitis. The Atlanta Classification's novelty was in emphasizing that extrapancreatic fat necrosis, which leads to walled-off necrosis, is associated with poor prognosis. Conversely, the free fluid liquid was considered to be less related to complications. The Atlanta's classification's main weakness is that it is mainly computed tomography (CT) based, as contrast-enhanced CT is the predominant imaging technique used for evaluating a wide range of pathological processes of acute pancreatitis. However, some local complications are difficult to distinguish accurately on CT. Recent advances, including significantly better soft-tissue contrast, favor multiparametric magnetic resonance imaging (mpMRI) for a more comprehensive assessment of acute pancreatitis pathology, particularly for small necrotic/fat debris within a collection. In addition, the MRI severity index (MRSI), which combines Balthazar's grade points and points of the extent of pancreatic necrosis, has been proven to be crucial for the initial evaluation, staging, and prognosis of acute pancreatitis. Other innovations, such as the recognition of important MRI features in acute pancreatitis and the utilization of newer, more effective terminology for imaging reporting assistance in the differentiation of the common local complications following this disease, have improved the treatment for acute pancreatitis. In this paper, with reference to the 2012 revised Atlanta classification, we review the strengths and limitations of MRI for identifying acute pancreatitis, the MRI findings of a spectrum of pathological entities, and the important local complications secondary to acute pancreatitis.

Management of infected pancreatic necrosis in the intensive care unit: a narrative review

BACKGROUND

Severe acute pancreatitis is marked by organ failure and (peri)pancreatic necrosis with local complications such as infected necrosis. Infection of these necrotic collections together with organ failure remain the major causes of admission to an intensive care unit (ICU) in acute pancreatitis. Appropriate treatment of infected necrosis is essential to reduce morbidity and mortality. Overall knowledge of the treatment options within a multidisciplinary team-with special attention to the appropriate use of antimicrobial therapy and invasive treatment techniques for source control-is essential in the treatment of this complex disease.

OBJECTIVES

To address the current state of microbiological diagnosis, antimicrobial treatment, and source control for infected pancreatic necrosis in the ICU.

SOURCES

A literature search was performed using the Medline and Cochrane libraries for articles subsequent to 2003 using the keywords: infected necrosis, pancreatitis, intensive care medicine, treatment, diagnosis and antibiotic(s).

CONTENT

This narrative review provides an overview of key elements of diagnosis and treatment of infected pancreatic necrosis in the ICU.

IMPLICATIONS

In pancreatic necrosis it is essential to continuously (re)evaluate the indication for antimicrobial treatment and invasive source control. Invasive diagnostics (e.g. through fine-needle aspiration, FNA), preferably prior to the start of broad-spectrum antimicrobial therapy, is advocated. Antimicrobial stewardship principles apply: paying attention to altered pharmacokinetics in the critically ill, de-escalation of broad-spectrum therapy once cultures become available, and early withdrawal of antibiotics once source control has been established. This is important to prevent the development of antimicrobial resistance, especially in a group of patients who may require repeated courses of antibiotics during the prolonged course of their illness.

MR imaging for acute pancreatitis: the current status of clinical applications

Acute pancreatitis is a common clinical acute abdomen. Imaging examinations play an important role in the management of acute pancreatitis. MR imaging is a noninvasive examination with high tissue contrast and a variety of acquisition sequences that can help determine the diagnosis, complications and severity of acute pancreatitis. The acute pancreatitis classification working group modified the Atlanta classification in 2012 to improve clinical evaluations and standardize the radiologic nomenclature for acute pancreatitis. In particular, the redefinition of necrotizing pancreatitis offers a new understanding of this disease. In clinical practice, there is still a lack of unifying standards between radiologists and physicians, such as for the imaging features of pseudocysts, walled-off necrosis, peripancreatic necrosis and especially for the MR imaging features of acute pancreatitis. In this article, we review the 2012 revised Atlanta classification of acute pancreatitis and recent advances in the clinical applications of MR imaging (MRI) in acute pancreatitis by showing how MRI can provide more optimized information for clinical diagnosis and treatment plan.

Management of (Peri)Pancreatic Collections in Acute Pancreatitis

The development of (peri)pancreatic fluid collections are frequent local complications in acute pancreatitis. These collections are classified as early (acute peripancreatic fluid collection or acute necrotic collection) or late (walled-off necrosis or pseudocyst). The majority of pancreatic fluid collections resolve spontaneously and do not require intervention. However, infection may require intervention. Interventions may include endoscopic or percutaneous catheter drainage, or in a next step endoscopic or surgical necrosectomy, minimally invasive or open. The best timing for the first intervention is still under investigation. Whereas some use antibiotics to postpone intervention until the stage of walled-off necrosis, others drain earlier. Endoscopic drainage of (peri)pancreatic fluid collections is now the preferred approach of drainage due to reduced morbidity as compared to surgical or percutaneous drainage. However, each collection must be treated according to a tailored approach. The final treatment should take into consideration anatomic characteristics, patient preference, comorbidity profile of the patient, and physician discretion. This review summarizes the current evidence on the treatment of (peri)pancreatic fluid collections.

Balloon dilator controls massive bleeding during endoscopic ultrasound-guided drainage for pancreatic pseudocyst: A case report and review of literature

Pancreatic pseudocyst (PPC), a common sequela of acute or chronic pancreatitis, was defined by the revised Atlanta classification as “a collection.” Endoscopic ultrasound (EUS)-guided drainage is often considered a standard first-line therapy for patients with symptomatic PPC. This effective approach exhibits 90%-100% technical success and 85%-98% clinical success. Bleeding is a deadly adverse event associated with EUS-guided drainage procedures, and the bleeding rate ranges from 3% to 14%. Hemostasis involves conservative treatment, endoscopy, interventional radiology-guided embolization and surgery. However, few studies have reported on EUS-guided drainage with massive, multiple hemorrhages related to severe pancreatogenic portal hypertension (PPH). Thus, the aim of this case report was to present a case using a balloon dilator to achieve successful hemostasis for PPH-related massive bleeding in EUS-guided drainage of PPC. To our knowledge, this method has not been previously reported.

Algorithm for the multidisciplinary management of hemorrhage in EUS-guided drainage for pancreatic fluid collections

Pancreatic fluid collections (PFCs), common sequelae of acute or chronic pancreatitis, are broadly classified as pancreatic pseudocysts or walled-off necrosis according to the revised Atlanta classification. Endoscopic ultrasound (EUS)-guided drainage is often considered a standard first-line therapy preferable to surgical or interventional radiology approaches for patients with symptomatic PFC. EUS-guided drainage is effective and successful; it has a technical success rate of 90%-100% and a clinical success rate of 85%-98%. Recent studies have shown a 5%-30% adverse events (AEs) rate for the procedure. The most common AEs include infection, hemorrhage, perforation and stent migration. Hemorrhage, a severe and sometimes deadly outcome, requires a well-organized and appropriate treatment strategy. However, few studies have reported the integrated management of hemorrhage during EUS-guided drainage of PFC. Establishing a practical therapeutic strategy is an essential and significant step in standardized management. The aim of this review is to describe the current situation of EUS-guided drainage of PFCs, including the etiology and treatment of procedure-related bleeding as well as current problems and future perspectives. We propose a novel and meaningful algorithm for systematically managing hemorrhage events. To our limited knowledge, a multidisciplinary algorithm for managing EUS-guided drainage for PFC-related bleeding has not been previously reported.

The Evolution of EUS-Guided Transluminal Drainage for the Treatment of Pancreatic Fluid Collections: A Comparison of Clinical and Cost Outcomes with Double-Pigtail Plastic Stents, Conventional Metal Stents and Lumen-Apposing Metal Stents

Background

While most pancreatic fluid collections (PFCs) resolve spontaneously, endoscopic ultrasound-guided transluminal drainage (EUS-TD) may be necessary. EUS-TD has evolved from multiple double-pigtail plastic stents (DPPS) to fully covered self-expanding metal stents (FCSEMS) and lumen-apposing metal stents (LAMS). This study compares clinical attributes of DPPS, FCSEMS and LAMS.

Methods

This is a single-centre retrospective review of EUS-TD for PFCs. The primary outcome was clinical success. Secondary outcomes were technical success, procedure time, hospital length of stay (HLOS), number of endoscopies, need for necrosectomy, adverse events (AEs) and overall cost.

Results

Fifty-eight patients (37 male, average age 49 years) underwent a total of 60 EUS-TD procedures for PFCs (average size 11.2 cm with 29 pseudocysts and 29 walled-off necrosis). Ten patients (17%) underwent EUS-TD with DPPS and 48 patients (83%) with metal stents (32 FCSEMS, 16 LAMS). Overall technical and clinical success was 100% and 84%, respectively. Lumen-apposing metal stents had shorter procedure times (14.9 versus 63.6 DPPS, 39.1 min FCSEMS, P < 0.001), and no difference in AEs (3 of 16 versus 4 of 10 DPPS, 12 of 34 FCSEMS, ns). Double-pigtail plastic stents required more endoscopies (3.7 versus 2.3 LAMS, 2.3 FCSEMS, P = 0.013) and necrosectomies (4 of 10 [40%]) compared with 5 of 34 [15%] in the FCSEMS group and 3 of 16 [19%] in the LAMS group, respectively, P = 0.001) to achieve clinical resolution. The overall cost and HLOS was not significantly different between groups.

Conclusion

The use of LAMS for PFCs is not associated with any significant increase in cost despite technical (shorter procedure time) and clinical advantages (shorter indwell time, reduced need for necrosectomy and no increase in AEs).

Review of management options for pancreatic pseudocysts

Pancreatic pseudocysts (PPs) present a challenging problem for physicians dealing with pancreatic disorders. Their management demands the co-operation of surgeons, radiologists and gastroenterologists. Historically, they have been treated either conservatively or surgically, with acceptable rates of complications and recurrence. However, recent advances in radiology and endoscopy, have leaded physicians to implement percutaneous and endoscopic drainage (ED) into their treatment algorithms. Moreover, laparoscopic surgery, with its advantages, has become an attractive alternative choice when surgical drainage (SD) is required. The aim of this review is to summarize the main diagnostic and therapeutic tools in the management of pseudocysts and to present the main studies that compare the three different types of pseudocyst drainage.

Intramural gastric pseudocyst: A case report and a comprehensive literature review

RATIONALE

Intramural pseudocyst, although first reported several decades ago, is a rare entity. Scientific knowledge regarding its clinical management is sparse.

PATIENT CONCERNS

We present three cases to show the diverse clinical patterns of patients diagnosed with an intramural gastric pseudocyst.

DIAGNOSIS

A final diagnosis should rest on proper evaluation by cross sectional imaging, including computer tomography and magnetic resonance imaging. Endoscopic ultrasound adds to the work-up.

INTERVENTIONS

Previously, identified "lesions of the gastric wall" were not well recognized as an intramural pseudocyst, and treatments including resectional surgery were employed. Contemporary proper diagnostics should provide support to a less aggressive treatment approach.

OUTCOMES

While an indolent natural history without any clinical symptoms or discomfort could be expected in most cases, individual clinical evaluation should be applied.

LESSONS

A heterogeneous information pattern from the limited number of cases in the literature makes it difficult to draw any firm conclusions. Attention to this rare condition should be increased to help clinicians arrive at a correct diagnosis and possibly prevent some patients from being over treated or from the use of unnecessary surgery.

Management of Inflammatory Fluid Collections and Walled-Off Pancreatic Necrosis

OPINION STATEMENT

Pancreatic fluid collections are a frequent complication of acute pancreatitis. The revised Atlanta criterion classifies chronic fluid collections into pseudocysts and walled-off pancreatic necrosis (WON). Symptomatic PFCs require drainage options that include surgical, percutaneous, or endoscopic approaches. With the advent of newer and more advanced endoscopic tools and expertise, minimally invasive endoscopic drainage has now become the preferred approach. An endoscopic ultrasonography (EUS)-guided approach for pancreatic fluid collection drainage is now the preferred endoscopic approach. Both plastic stents and metal stents are efficacious and safe; however, metal stents may offer an advantage, especially in infected pseudocysts and in WON. Direct endoscopic necrosectomy is often required in WON. Lumen apposing metal stents allow for direct endoscopic necrosectomy and debridement through the stent lumen and are now preferred in these patients. Endoscopic retrograde cholangiopancreatography with pancreatic duct exploration should be performed concurrent to PFC drainage in patients with suspected PD disruption. PD disruption is associated with an increased severity of pancreatitis, an increased risk of recurrent attacks of pancreatitis and long-term complications, and a decreased rate of PFC resolution after drainage. Ideally, pancreatic ductal disruption should be bridged with endoscopic stenting.

Endoscopic management of pancreatic fluid collections-revisited

The development of pancreatic fluid collections (PFC) is one of the most common complications of acute severe pancreatitis. Most of the acute pancreatic fluid collections resolve and do not require endoscopic drainage. However, a substantial proportion of acute necrotic collections get walled off and may require drainage. Endoscopic drainage of PFC is now the preferred mode of drainage due to reduced morbidity and mortality as compared to surgical or percutaneous drainage. With the introduction of new metal stents, the efficiency of endoscopic drainage has improved and the task of direct endoscopic necrosectomy has become easier. The requirement of re-intervention is less with new metal stents as compared to plastic stents. However, endoscopic drainage is not free of adverse events. Severe complications including bleeding, perforation, sepsis and embolism have been described with endoscopic approach to PFC. Therefore, the endoscopic management of PFC is a multidisciplinary affair and involves interventional radiologists as well as GI surgeons to deal with unplanned adverse events and failures. In this review we discuss the recent advances and controversies in the endoscopic management of PFC.

Accuracy of contrast-enhanced ultrasound compared with conventional ultrasound in acute pancreatitis: Diagnosis and complication monitoring

Contrast-enhanced ultrasound (CEUS) has been used for diagnosing acute pancreatitis (AP), particularly severe acute pancreatitis (SAP). However, the diagnostic difference between CEUS and conventional ultrasonography (CUS) for AP and SAP has not been reported. The aim of the present study was to investigate the diagnostic accuracy of CUS and CEUS for AP. A total of 196 patients clinically diagnosed with AP were selected. All patients underwent CUS, CEUS and contrast-enhanced computed tomography (CECT) within 72 h. CECT was considered the gold standard. Pancreatic size, peripancreatic fluid collection (PPFC) and splenic vessel complications were the variables observed by CUS and CEUS. The differences in the variables among the three methods were analyzed using the χ2 test and statistical analysis software. Significant differences in pancreatic size, PPFC and splenic vessel complications in AP were observed between CEUS and CUS (P<0.05). χ2 test results indicated that CEUS significantly differed from CUS in terms of having a higher diagnostic accuracy for AP and SAP (P<0.05). The results indicate that CEUS is a reliable method for the diagnosis and monitoring of AP and SAP, and may be substituted for CECT.

Evaluation of the short- and long-term effectiveness and safety of fully covered self-expandable metal stents for drainage of pancreatic fluid collections: results of a Spanish nationwide registry

BACKGROUND AND AIMS

Initial reports suggest that fully covered self-expandable metal stents (FCSEMSs) may be better suited for drainage of dense pancreatic fluid collections (PFCs), such as walled-off pancreatic necrosis. The primary aim was to analyze the effectiveness and safety of FCSEMSs for drainage of different types of PFCs in a large cohort. The secondary aim was to investigate which type of FCSEMS is superior.

METHODS

This was a retrospective, noncomparative review of a nationwide database involving all hospitals in Spain performing EUS-guided PFC drainage. From April 2008 to August 2013, all patients undergoing PFC drainage with an FCSEMS were included in a database. The main outcome measurements were technical success, short-term (2 weeks) and long-term (6 months) effectiveness, adverse events, and need for surgery.

RESULTS

The study included 211 patients (pseudocyst/walled-off pancreatic necrosis, 53%/47%). The FCSEMSs used were straight biliary (66%) or lumen-apposing (34%). Technical success was achieved in 97% of patients (95% confidence interval [CI], 93%-99%). Short-term- and long-term clinical success was obtained in 94% (95% CI, 89%-97%) and 85% (95% CI, 79%-89%) of patients, respectively. Adverse events occurred in 21% of patients (95% CI, 16%-27%): infection (11%), bleeding (7%), and stent migration and/or perforation (3%). By multivariate analysis, patient age (>58 years) and previous failed drainage were the most important factors associated with negative outcome.

CONCLUSIONS

An FCSEMS is effective and safe for PFC drainage. Older patients with a history of unsuccessful drainage are more likely to fail EUS-guided drainage. The type of FCSEMS does not seem to influence patient outcome.