Imaging assessment of acute pancreatitis: a review

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.

Value of Dual-Energy CT Perfusion Analysis in Patients with Acute Pancreatitis: Correlation and Discriminative Diagnostic Accuracy with Varying Disease Severity

Background: This study investigates the correlation and discriminative diagnostic accuracy of dual-energy CT (DECT)-derived imaging biomarkers in patients with acute pancreatitis of varying severity. Methods: In this retrospective study, we included 51 patients with acute pancreatitis who had undergone portal-venous phase DECT of the abdomen. Three blinded readers independently performed region-of-interest measurements on DECT images in the inflammatory pancreatic parenchyma. The correlation between modified CT severity index (CTSI) and quantitative imaging parameters was investigated using Pearson correlation coefficient. We performed receiver operator curve (ROC) analysis to assess diagnostic accuracy of the quantitative image parameters for the differentiation between mild/moderate versus severe acute pancreatitis. The optimal discriminative cut-off value to diagnose severe acute pancreatitis was determined using the Youden index. Results: Moderate correlations were found between CTSI scores and iodine density (Pearson’s correlation coefficient r = −0.65; p < 0.001), as well as attenuation (r = −0.55; p < 0.001) and normalized iodine uptake (r = −0.50; p < 0.001). ROC curve analysis revealed highest ability to differentiate mild/moderate from severe acute pancreatitis for iodine density (AUC = 0.86, 95% confidence interval 0.75 to 0.97). An optimal iodine density threshold of ≤1.63 mg/mL was found to indicate severe acute pancreatitis with a sensitivity of 81.3% and specificity of 77.1%. Conclusion: DECT-derived iodine density correlates with acute pancreatitis severity and may facilitate prediction of severe acute pancreatitis.

Utility of ultrasound in acute pancreatitis

Ultrasound plays an essential role in the initial evaluation of patients with suspected or confirmed acute pancreatitis. In addition to evaluation of the pancreatic parenchyma, ultrasound is used for assessment of the gallbladder, biliary tree, peripancreatic tissues, and regional vascular structures. While enlarged and edematous pancreas are classic sonographic features of acute pancreatitis, the pancreas may appear sonographically normal in the setting of acute pancreatitis. Nonetheless, sonographic evaluation in this setting is valuable because assessment for etiologic factors such as gallstones or evidence of biliary obstruction are best performed with ultrasound. Complications of pancreatitis such as peripancreatic fluid collections, venous thrombosis, or arterial pseudoaneurysm can be identified with careful and focused ultrasound examination. Knowledge of various scanning techniques can help to mitigate some of the commonly encountered barriers to sonographic visualization of the pancreas and right upper quadrant structures. Ultrasound can also be used for guidance of percutaneous treatment such as drainage of fluid collections or pseudoaneurysm thrombosis. Difficulty in differentiating edematous from necrotizing pancreatitis can be mitigated with the use of contrast-enhanced ultrasound to assess pancreatic parenchymal enhancement.

Comparison of clinical findings in 293 dogs with suspect acute pancreatitis: Different clinical presentation with left lobe, right lobe or diffuse involvement of the pancreas

Pancreatitis is a common clinical condition seen in companion animals. The correlation of the region of the pancreas affected to the presentation of clinical signs has not been previously described. A retrospective study on the clinical findings in 293 client-owned dogs diagnosed with suspect pancreatitis based on history, clinical signs, laboratory testing and abdominal ultrasonography was performed. Based on ultrasonography, dogs were divided into three groups: group 1: 41 dogs with ultrasonographic changes consistent with pancreatitis within the left lobe of the pancreas; group 2: 105 dogs with ultrasonographic changes compatible with pancreatitis within the right lobe of the pancreas; and group 3: 147 dogs with ultrasonographic evidence of diffuse pancreatitis. No significant differences regarding age, breed and sex were evident. Furthermore, statistical significance was demonstrated with the presence of pain in group 3; poor appetite in groups 2 and 3; and vomiting and diarrhoea in group 3. Pain is expected to occur with a higher frequency in diffuse pancreatitis, but it is not a common clinical sign. This may represent a more severe form of the disease when the pancreas is diffusely affected. Vomiting was more common than diarrhoea with both clinical signs more prevalent in dogs with diffuse pancreatitis, and this could be ascribed to gastric and intestinal tract involvement. Poor appetite occurred more frequently in dogs with diffuse and right lobe pancreatitis. A possible explanation can be attributed to the fact that the duodenum has many receptors and is referred to as the 'organ of nausea'.

CT angiographic changes in dogs with acute pancreatitis: A prospective longitudinal study

Computed tomographic angiography (CTA) has recently been shown to be a useful tool in the diagnosis of acute canine pancreatitis, the identification of pancreatic necrosis, and the detection of sequelae. Evidence of pancreatic necrosis on CTA has been shown to be correlated with a poorer outcome in both humans and dogs and early diagnosis and intervention may improve outcomes. In humans, pancreatic necrosis is typically evident on CTA within 48 h of clinical signs, thus, repeat CTA examinations are often performed to identify pancreatic necrosis that may not have been evident on CTA examinations performed early in the course of disease. Published information investigating the timing of CTA examinations and the use of serial CTA in dogs with acute pancreatitis is lacking. In this prospective, longitudinal study, CTA examinations were performed at the time of hospitalization and repeated 3-5 days later in 11 dogs suffering from acute canine pancreatitis to determine if pancreatic necrosis or sequelae are under diagnosed on examinations performed at the time of hospitalization. Computed tomographic angiography studies were evaluated for changes in pancreatic size, pancreatic contrast enhancement, and peri-pancreatic tissues and vessels. The only statistically significant difference between the initial and repeat CTA examinations was the improvement of fat stranding on the repeat CTA examinations (P < .045). Based on these results, CTA performed at the time of admission is likely adequate in the diagnosis and evaluation of dogs with acute pancreatitis. Repeat CTA examinations are unlikely to add additional information in the absence of worsening clinical signs.

Abdominal ultrasonography for patients with abdominal pain as a first-line diagnostic imaging modality

The utility and limitations of abdominal ultrasonography (US) were retrospectively evaluated as a first-line diagnostic imaging modality in patients with abdominal pain. Hospital records from patients subjected to abdominal US as a first-line diagnostic imaging examination at the National Hospital Organization Shimoshizu Hospital (Yotsukaido, Japan) from April 2010 to April 2015 were analyzed. Only those patients who underwent abdominal US to diagnose abdominal symptoms were included in the present study. All patients with prior diagnostic imaging examination findings were excluded from the study in order to reduce bias of results. The analyzed patients included 39 males with an average (mean ± standard deviation) age of 65.8±18.8 years and 37 females with an average age of 53.7±19.3 years. Diagnosis with abdominal US was in agreement with the final diagnosis in 66 of the 76 patients. Final diagnosis of symptoms by abdominal US was not successful in the remaining 10 patients who required further investigation. Acute cholangitis, acute cholecystitis, acute pancreatitis, acute appendicitis, colonic diverticulitis and spleen rupture were correctly diagnosed. Different types of cancer, including colorectal cancer, were also successfully diagnosed. Bile duct cancer and sigmoid colon volvulus could not be diagnosed by abdominal US due to the presence of intestinal gas. Abnormal findings were detected using abdominal US, but the diagnosis required additional consultation with gynecologists. Abdominal US was suitable for patients with abdominal symptoms. It is recommended that patients undergo further diagnostic imaging or consultation with gynecologists when large gas bubbles are present or gynecological conditions are suspected.

Diagnostic Imaging of the Hepatobiliary System: An Update

Recent advances in diagnostic imaging of the hepatobiliary system include MRI, computed tomography (CT), contrast-enhanced ultrasound, and ultrasound elastography. With the advent of multislice CT scanners, sedated examinations in veterinary patients are feasible, increasing the utility of this imaging modality. CT and MRI provide additional information for dogs and cats with hepatobiliary diseases due to lack of superimposition of structures, operator dependence, and through intravenous contrast administration. Advanced ultrasound methods can offer complementary information to standard ultrasound imaging. These newer imaging modalities assist clinicians by aiding diagnosis, prognostication, and surgical planning.

MDCT of acute pancreatitis: Intraindividual comparison of single-phase versus dual-phase MDCT for initial assessment of acute pancreatitis using different CT scoring systems

OBJECTIVES

The purpose of the retrospective study was to evaluate the additional value of dual-phase multidetector computed tomography (MDCT) protocols over a single-phase protocol on initial MDCT in patients with acute pancreatitis using three CT-based pancreatitis severity scores with regard to radiation dose.

METHODS

In this retrospective, IRB approved study MDCT was performed in 102 consecutive patients (73 males; 55years, IQR48-64) with acute pancreatitis. Inclusion criteria were CT findings of interstitial edematous pancreatitis (IP) or necrotizing pancreatitis (NP) and a contrast-enhanced dual-phase (arterial phase and portal-venous phase) abdominal CT performed at ≥72h after onset of symptoms. The severity of pancreatic and extrapancreatic changes was independently assessed by 2 observers using 3 validated CT-based scoring systems (CTSI, mCTSI, EPIC). All scores were applied to arterial phase and portal venous phase scans and compared to score results of portal venous phase scans, assessed ≥14days after initial evaluation. For effective dose estimation, volume CT dose index (CTDIvol) and dose length product (DLP) were recorded in all examinations.

RESULTS

In neither of the CT severity scores a significant difference was observed after application of a dual-phase protocol compared with a single-phase protocol (IP: CTSI: 2.7 vs. 2.5, p=0.25; mCTSI: 4.0 vs. 4.0, p=0.10; EPIC: 2.0 vs. 2.0, p=0.41; NP: CTSI: 8.0 vs. 7.0, p=0.64; mCTSI: 8.0 vs. 8.0, p=0.10; EPIC: 3.0 vs. 3.0, p=0.06). The application of a single-phase CT protocol was associated with a median effective dose reduction of 36% (mean dose reduction 31%) compared to a dual-phase CT scan.

CONCLUSIONS

An initial dual-phase abdominal CT after ≥72h after onset of symptoms of acute pancreatitis was not superior to a single-phase protocol for evaluation of the severity of pancreatic and extrapancreatic changes. However, the effective radiation dose may be reduced by 36% using a single-phase protocol.

Pancreatitis: A Forensic Perspective

Among the numerous etiologies of acute and chronic pancreatitis, several underlying causes (e.g., chronic alcohol abuse, trauma, medical therapy) may result in a death that is reportable to the medical examiner/coroner. As such, forensic pathologists are likely to encounter pancreatitis at autopsy and therefore must be familiar with its etiologies, mechanisms of death, autopsy findings, and medicolegal investigation. This review will focus on the aspects of pancreatitis that may be useful to forensic pathologists in their daily practice. This includes determining if acute or chronic pancreatitis caused or contributed to death as well as determining the etiologically specific proximate cause of death. Current theories of how these various processes result in inflammation of the pancreas are reviewed.

Computed Tomography and MRI of the Hepatobiliary System and Pancreas

MRI and computed tomographic (CT) imaging are becoming more common in the diagnosis of hepatobiliary and pancreatic disorders in small animals. With the advent of multislice CT scanners, sedated examinations in veterinary patients are feasible increasing the use of this imaging modality. CT and MRI provide additional information for dogs and cats with hepatobiliary and pancreatic diseases because of lack of superimposition of structures, operator dependence, and through intravenous contrast administration. This added value provides more information for diagnosis, prognosis, and surgical planning.

Computed tomographic angiography under sedation in the diagnosis of suspected canine pancreatitis: a pilot study

Background

Computed tomography (CT) is highly accurate for diagnosing pancreatitis in humans. The diagnosis of pancreatitis in dogs is based on clinical signs, laboratory findings, and ultrasonographic (US) changes. There are, however, inherent limitations in relying on laboratory and ultrasound findings for the clinical diagnosis of pancreatitis in dogs.

Hypothesis/Objectives

We hypothesized that CT angiography would be a rapid and reliable method to confirm pancreatitis in dogs compared to ultrasonography. The aim was to describe the CT characteristics and compare them to ultrasound findings and correlate the CT appearance to the severity of the patients' clinical course.

Animals

A prospective pilot case series; 10 dogs with pancreatitis were enrolled if the history, clinical signs, laboratory, and ultrasonographic findings were indicative of pancreatitis.

Methods

A 3‐phase angiographic CT was performed under sedation. Afterward, each dog had US‐guided aspirates of the pancreas collected and blood drawn for cPLi assay. Images were evaluated for portion of visible pancreas, pancreatic size and margin, pancreatic parenchyma, presence of peripancreatic changes and contrast enhancement pattern. The results were compared with outcome.

Results

An enlarged, homogeneously to heterogeneously attenuating and contrast‐enhancing pancreas with ill‐defined borders was identified in all dogs. CT identified more features characterizing pancreatic abnormalities compared to US. Thrombi were found in 3/10 dogs. Three dogs with heterogeneous contrast enhancement had an overall poorer outcome than those with homogenous enhancement.

Conclusions and Clinical Importance

CT angiography under sedation was used in dogs to confirm clinically suspected pancreatitis and identified clinically relevant and potentially prognostic features of pancreatitis in dogs.

Single-portal-phase low-tube-voltage dual-energy CT for short-term follow-up of acute pancreatitis: evaluation of CT severity index, interobserver agreement and radiation dose

OBJECTIVES

To intra-individually compare single-portal-phase low-tube-voltage (100-kVp) computed tomography (CT) with 120-kVp images for short-term follow-up assessment of CT severity index (CTSI) of acute pancreatitis, interobserver agreement and radiation dose.

METHODS

We retrospectively analysed 66 patients with acute pancreatitis who underwent initial dual-contrast-phase CT (unenhanced, arterial, portal phase) at admission and short-term (mean interval 11.4 days) follow-up dual-contrast-phase dual-energy CT. The 100-kVp and linearly blended images representing 120-kVp acquisition follow-up CT images were independently evaluated by three radiologists using a modified CTSI assessing pancreatic inflammation, necrosis and extrapancreatic complications. Scores were compared with paired t test and interobserver agreement was evaluated using intraclass correlation coefficients (ICC).

RESULTS

Mean CTSI scores on unenhanced, portal- and dual-contrast-phase images were 4.9, 6.1 and 6.2 (120 kVp) and 5.0, 6.0 and 6.1 (100 kVp), respectively. Contrast-enhanced series showed a higher CTSI compared to unenhanced images (P < 0.05) but no significant differences between single- and dual-contrast-phase series (P > 0.7). CTSI scores were comparable for 100-kVp and 120-kVp images (P > 0.05). Interobserver agreement was substantial for all evaluated series and subcategories (ICC 0.67-0.93). DLP of single-portal-phase 100-kVp images was reduced by 41 % compared to 120-kVp images (363.8 versus 615.9 mGy cm).

CONCLUSIONS

Low-tube-voltage single-phase 100-kVp CT provides sufficient information for follow-up evaluation of acute pancreatitis and significantly reduces radiation exposure.

KEY POINTS

• Single-portal-phase CT provides sufficient evaluation for follow-up of acute pancreatitis. • Follow-up CT does not benefit from unenhanced or arterial-phase acquisition. • CT severity index scores are equal for dual-contrast-phase 100-/120-kVp acquisition (P > 0.05). • 100-kVp single-portal-phase follow-up CT of acute pancreatitis significantly reduces radiation exposure.

The normal transverse mesocolon and involvement of the mesocolon in acute pancreatitis: an MRI study

Objective

To study the MRI findings of the normal transverse mesocolon and the involvement of the mesocolon in acute pancreatitis (AP) as well as the relationship between the involvement of the mesocolon and the severity of AP.

Materials and Methods

Forty patients without pancreatic disorders were retrospectively analyzed to observe the normal transverse mesocolon using MRI; 210 patients with AP confirmed by clinical and laboratory tests were retrospectively analyzed using MRI to observe transverse-mesocolon involvement (TMI). The severity of TMI was recorded as zero points (no abnormalities and transverse-mesocolon vessel involvement), one point (linear and patchy signal in the transverse mesocolon) or two points (transverse-mesocolon effusion). The AP severity was graded by the MRI severity index (MRSI) and the Acute Physiology And Chronic Healthy Evaluation II (APACHE II) scoring system. The correlations of TMI with MRSI and APACHE-II were analyzed.

Results

In a normal transverse mesocolon, the display rates of the middle colic artery, the middle colic vein and the gastrocolic trunk on MRI were 95.0%, 82.5% and 100.0%, respectively. Of the 210 patients with AP, 130 patients (61.9%) had TMI. According to the TMI grading, 40%, 39% and 20% of the patients were graded at zero, one and two points, respectively. TMI was strongly correlated with the MRSI score (r = 0.759, P = 0.000) and the APACHE-II score (r = 0.384, P = 0.000).

Conclusion

MRI could be used to visualize transverse-mesocolon involvement. The severity of TMI could reflect that of AP in the clinical setting and imaging. TMI might be a supplementary indicator of the severity of AP.

Imaging of acute pancreatitis and its complications. Part 1: acute pancreatitis

Acute pancreatitis is an acute inflammatory disease of the pancreas that may also involve surrounding tissues or remote organs. The Atlanta classification of acute pancreatitis was introduced in 1992 and divides patients into mild and severe groups based on clinical and biochemical criteria. Recently, the terminology and classification scheme proposed at the initial Atlanta Symposium have been reviewed and a new consensus statement has been proposed by the Acute Pancreatitis Classification Working Group. Generally, imaging is recommended to confirm the clinical diagnosis, investigate the etiology, and grade the extend and severity of the acute pancreatitis. Ultrasound is the first-line imaging modality in most centers for the confirmation of the diagnosis of acute pancreatitis and the ruling out of other causes of acute abdomen, but it has limitations in the acute clinical setting. Computed tomography not only establishes the diagnosis of acute pancreatitis, but also enables to stage severity of the disease. Magnetic resonance imaging has earned an ever more important role in the diagnosis of acute pancreatitis. It is especially useful for imaging of patients with iodine allergies, characterizing collections and assessment of an abnormal or disconnected pancreatic duct. The purpose of this review article is to present an overview of the acute pancreatitis, clarify confusing terminology, underline the role of ultrasound, computed tomography and magnetic resonance imaging according to the proper clinical context and compare the advantages and limitations of each modality.

Outcome assessment in acute pancreatitis patients

Early diagnosis and severity evaluation in patients with acute pancreatitis (AP) are very important due to its potential morbidity and mortality. Several clinical, laboratory, and radiologic factors, and many scoring systems have been proposed for outcome prediction. Although the Ranson and Acute Physiology and Chronic Health Evaluation II scoring systems have been widely used for decades, the cumbersome components partly limit their predictability. Recently, the Bedside Index for Severity in AP scoring system and series blood urea nitrogen changes, which are simple and convenient to evaluate within 24 hours after admission, have been validated for accuracy by several large-cohort studies. The presence of organ failure and systemic inflammatory response syndrome are also helpful to evaluate the severity of AP. Herein we review recent advances of the predictive methods for AP to provide an up-to-date perspective on outcome assessment of AP.

Involvement of thrombopoietin in acinar cell necrosis in L-arginine-induced acute pancreatitis in mice

Thrombopoietin (TPO) plays an important role in injuries of different tissues. However, the role of TPO in acute pancreatitis (AP) is not yet known. The aim of the study was to determine the involvement of TPO in AP. Serum TPO was assayed in necrotizing pancreatitis induced by L-arginine in mice. Recombinant TPO and anti-TPO antibody were given to mice with necrotizing pancreatitis. Amylase, lipase, lactate dehydrogenase, myeloperoxidase activity and pancreatic water content were assayed in serum and tissue samples. Pancreas and lung tissue samples were also collected for histological evaluation. Immunohistochemistry of amylase α and PCNA were applied for the study of acinar regeneration and TUNEL assay for the detection of apoptosis in the pancreas. Increased levels of serum TPO were found in necrotizing pancreatitis. After TPO administration, more severe acinar necrosis was found and blockade of TPO reduced the acinar necrosis in this AP model. Acinar regeneration and apoptosis in the pancreas were affected by TPO and antibody treatment in necrotizing pancreatitis. The severity of pancreatitis-associated lung injury was worsened after TPO treatment, but attenuated after Anti-TPO antibody treatment. In conclusion, serum TPO is up-regulated in the necrotizing pancreatitis induced by L-arginine in mice and may be a risk factor for the pancreatic acinar necrosis in AP. As a pro-necrotic factor, blockade of TPO can attenuate the acinar necrosis in AP and may be a possible therapeutic intervention for AP.

Renal and perirenal space involvement in acute pancreatitis: An MRI study

OBJECTIVES

To study the prevalence and characteristics of renal and perirenal space involvement and its relation to the severity of acute pancreatitis (AP) using MRI.

METHODS

115 patients with AP who underwent MRI with the clinical kidney function test were retrospectively analyzed in this study. MRI sequences included conventional and diffusion weighted imaging (DWI) sequences. The renal and perirenal space involvement in AP was noted on MRI. The renal apparent diffusion coefficient (ADC) on DWI was measured for each kidney. The severity of AP on MRI was graded using MR severity index (MRSI). The relationships among the renal and perirenal space involvement on MRI, the renal ADC, MRSI and the results of the kidney function test were analyzed.

RESULTS

In the 115 patients with AP, the renal and perirenal space abnormalities detected included renal parenchymal abnormalities (0.8%), abnormalities of the renal collecting system (2.6%), renal vascular abnormalities (1.7%), thickened renal fascia (99%), perirenal stranding (62%) and perirenal fluid collection (40%). The prevalence of perirenal space abnormalities was correlated with the severity of AP based on MRSI (P<0.05). The renal ADC values were lower in patients with abnormal kidney function than in those without kidney injury (P<0.05). The prevalence of kidney function abnormalities was 9.4%, 32% and 100% in mild, moderate, and severe AP cases, respectively (P=0.00).

CONCLUSION

Perirenal space involvement is much more than renal parenchymal involvement in AP. The prevalence of perirenal space involvement in AP on MRI has a positive correlation with the severity of AP according to MRSI.

MR imaging of acute pancreatitis: correlation of abdominal wall edema with severity scores

OBJECTIVE

To study MRI findings of abdominal wall edema (AWE) in acute pancreatitis as well as correlations between AWE and the severity of acute pancreatitis according to the MR severity index (MRSI) and the Acute Physiology And Chronic Healthy Evaluation III (APACHE III) scoring system.

MATERIALS AND METHODS

A total of 160 patients with AP admitted to our institution between December 2009 and March 2011 were included in this study. MRI was performed within 48 h after admission. MRI findings of acute pancreatitis were noted, including AWE on the MRI. The abdominal wall area was divided into quarters, and each area involved was recorded as 1 point to score the severity of AWE. The severity of acute pancreatitis was studied using both the MRSI and the APACHE III scoring system. Spearman correlation of AWE with the MRSI and the APACHE III scoring system was analyzed.

RESULTS

In 160 patients with acute pancreatitis, 53.8% had AWE on MRI. The average AWE score was 1.2±1.4 points. The prevalence of AWE was 30.5%, 64.5% and 100% in mild, moderate and severe AP, respectively, according to MRSI. AWE on MRI was correlated with MRSI scores (r=0.441, p=0.000). According to APACHE III scores, the averages were 2.0±1.1 and 2.6±1.1 points in mild AP and severe AP, respectively (P=0.016). AWE was slightly correlated with the APACHE III scores (r=0.222, p=0.005).

CONCLUSION

AWE on MRI in acute pancreatitis is common, which may be a supplementary indicator in determining the severity of AP.

Acute pancreatitis: the role of imaging in diagnosis and management

Acute pancreatitis is one of the more commonly encountered aetiologies in the emergency setting and its incidence is rising. Presentations range from a mild-self limiting condition which usually responds to conservative management to one with significant morbidity and mortality in its most severe forms. While clinical criteria are necessary to make the initial diagnosis, contrast-enhanced CT is the mainstay of imaging and has a vital role in assessing the extent and evolution of the disease and its associated complications. The purpose of this article is to summarise the natural course of acute severe pancreatitis, clarify confusing nomenclature, demonstrate the morphological stages in conjunction with radiological scoring systems and illustrate the complications. We will review and illustrate the increasing and significant role interventional radiology has in the management of these patients, which are often life-saving and surgery-sparing.

Magnetic resonance imaging for acute pancreatitis

Acute pancreatitis is characterized by acute chemical injury of the pancreatic parenchyma and peripancreatic tissue. The increased frequency of death in acute pancreatitis is directly correlated with the degree and progress of pancreatic necrosis. Moreover, the occurrence of some local complications in acute pancreatitis, such as pancreatic hemorrhage, peripancreatic abscess or large pseudocyst, and pseudoaneurysm, could influence the choice of treatment for these patients. Magnetic resonance imaging (MRI) can be used to help evaluate the presence and degree of pancreatic necrosis, and is crucial for identifying complications of acute pancreatitis and predicting prognosis. The purpose of this article is to describe MRI techniques for acute pancreatitis, to review the spectrum of pancreatic and peripancreatic patterns, as well as to survey various complications secondary to acute pancreatitis on MRI. The role of MRI in the initial evaluation and staging of acute pancreatitis is emphasized.