Acute interstitial edematous pancreatitis: Findings on non-enhanced MR imaging

Acute pancreatitis associated with pleural effusion: MDCT manifestations and anatomical basis

BACKGROUND

Acute pancreatitis (AP) is a severe condition with complications that can impact multiple organ systems throughout the body. Specifically, the diffusion of peripancreatic effusion to the pleural cavity is a significant phenomenon in AP. However, its pathways and implications for disease severity are not fully understood.

OBJECTIVE

This study aims to investigate the anatomical routes of peripancreatic effusion diffusion into the pleural cavity in patients with AP and to analyze the correlation between the severity of pleural effusion (PE) and the computed tomography severity index (CTSI) and acute physiology and chronic health evaluation II (APACHE II) scoring system.

METHODS

119 patients with AP admitted to our institution were enrolled in this study (mean age 50 years, 74 male and 45 female). Abdominal CT was performed, and the CTSI and APACHE II index were used to evaluate the severity of the AP, Meanwhile, the prevalence and semiquantitative of PE were also mentioned. The anatomical pathways of peripancreatic effusion draining to pleural were analyzed. Finally, the correlation relationship between the severity of AP and the PE was analyzed.

RESULTS

In 119 patients with AP, 74.8% of patients had PE on CT. The anatomic pathways of peripancreatic effusion draining to pleural included esophageal hiatus in 33.7% of patients, aortic hiatus in 6.7% of patients and inferior vena cava hiatus in 3.37% of patients. The rating of PE on CT was correlated with CTSI scores (r= 0.449, P= 0.000) and was slightly correlated with the APACHE II scores (r= 0.197, P= 0.016).

CONCLUSION

PE is a common complication of AP, which can be caused by anatomic pathways such as diaphragmatic hiatus. Due to its correlation with the CTSI score, the PE may be a supplementary indicator in determining the severity of AP.

Pancreatic enlargement in a patient receiving therapy with vasodilators for pulmonary arterial hypertension: a case report

Epoprostenol is a prostacyclin (prostaglandin I2) analog that causes vasodilation and inhibits platelet aggregation and is used in the management of severe pulmonary arterial hypertension (PAH). We herein report a patient with PAH who developed pancreatic enlargement after the initiation of therapy including epoprostenol. Although it is well known that thyroid enlargement occurs in patients with PAH receiving epoprostenol therapy, the pancreatic findings associated with epoprostenol therapy have not been well described. Although the size of the pancreas was clearly increased, there was no blood data or symptoms suggestive of abnormal pancreatic function and pancreatitis, and the patient's abdominal complaints improved quickly, despite the continuation of epoprostenol therapy. Eleven months after the start of continuous intravenous epoprostenol infusion therapy, the pancreatic enlargement was still evident on imaging, but there were no abdominal symptoms or elevated pancreatic enzymes. This case highlights the fact that epoprostenol therapy may cause pancreatic changes that mimic acute or autoimmune pancreatitis.

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.

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.

Acute pancreatitis with gradient echo T2*-weighted magnetic resonance imaging

BACKGROUND

To study gradient recalled echo (GRE) T2*-weighted imaging (T2*WI) for normal pancreas and acute pancreatitis (AP).

METHODS

Fifty-one patients without any pancreatic disorders (control group) and 117 patients with AP were recruited. T2* values derived from T2*WI of the pancreas were measured for the two groups. The severity of AP was graded by the magnetic resonance severity index (MRSI) and the Acute Physiology and Chronic Healthy Evaluation II (APACHE II) scoring system. Logistic regression was used to analyze the relationship between the T2* values and AP severity. The usefulness of the T2* value for diagnosing AP and the relationship between the T2* values and the severity of AP were analyzed.

RESULTS

On GRE-T2*WI, the normal pancreas showed a well-marinated and consistently homogeneous isointensity. Edematous AP, as well as the non-necrotic area in necrotizing AP, showed ill-defined but homogeneous signal intensity. AP with pancreatic hemorrhage showed a decreased T2* value and a signal loss on the signal decay curve. The T2* value of pancreas in the AP group was higher than that of the control group (t=-8.20, P<0.05). The T2* value tended to increase along with the increase in MRSI scores but not with the APACHE II scores (P>0.05). AP was associated with a one standard deviation increment in the T2* value (OR =1.37; 95% CI: 1.216-1.532).

CONCLUSIONS

T2*WI demonstrates a few characteristics of the normal pancreas and AP, which could potentially be helpful for detecting hemorrhage, and contributes to diagnosing AP and its severity.

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.

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.

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.

Imaging assessment of acute pancreatitis: a review

Acute pancreatitis is one of the more commonly encountered etiologies in the emergency setting. While in the majority of cases it is a self-limiting disease which responds rapidly to conservative management, in some cases acute pancreatitis may present with a more pronounced, sometimes dramatic, clinical picture and requires immediate medical care to avoid fatal complication. In this context, imaging plays a significant role because it enables identification of the development of the disease and local/systemic complications. The purpose of this article is to offer an overview of the disease and a spectrum of imaging findings in patients with acute pancreatitis, emphasizing the role of ultrasound, computed tomography, and magnetic resonance imaging according to the appropriate clinical context and advantages and limitations of each imaging modality are examined.

Markers for predicting severity and progression of acute pancreatitis

Several tools have been developed for severity stratification in acute pancreatitis. They include single biochemical markers, imaging methods, and complex scoring systems, all of which aim at an early detection of severe acute pancreatitis to optimise monitoring and treatment of patients as early as possible. Among single biochemical markers, C-reactive protein (CRP) remains the most useful. Despite its delayed increase, peaking not earlier than 72 h after the onset of symptoms, it is accurate and widely available. Many other markers have been evaluated for their usefulness, and for some of them very promising data could be shown. Among them interleukin 6 seems to be the most promising parameter for use in clinical routine. For the detection of pancreatic infection, procalcitonin is the most sensitive, and can be used as an indicator for the need for fine-needle aspiration of pancreatic necrosis. Regarding imaging, contrast-enhanced computed tomography is still the reference method for the detection of necrotising acute pancreatitis. Pancreatitis-specific scoring systems have been shown to be of value for the prediction of severity and progression of acute pancreatitis, but cannot be applied any earlier than 48 h after admission to hospital. The APACHE-II score has not been developed specifically for acute pancreatitis and is rather complex to assess, but has been proven to be an early and reliable tool. Indication, timing and consequences of the methods applied need to be carefully considered and incorporated into clinical assessments to avoid costs and harm to the patient.