Fat-modified computed tomography severity index (CTSI) is a better predictor of severity and outcome in patients with acute pancreatitis compared with modified CTSI

Endoscopic ultrasound-guided pancreatic duct drainage: a comprehensive state of the art review

INTRODUCTION

Endoscopic retrograde pancreatography (ERP) has traditionally been the standard modality for pancreatic endotherapy. However, in certain situations, failure of retrograde ductal access may warrant an alternative modality of drainage. This can occur in various settings like difficult and/or surgically altered anatomy or duodenal obstruction. Endoscopic ultrasound-guided pancreatic duct drainage (EUS-PDD) is a relatively newer addition to the armamentarium for endoscopic access to the PD.

AREAS COVERED

This comprehensive state-of-art review aims to give an overview of the indications, technical details, different approaches, and outcomes of EUS-PDD, with the latest evidence available in scientific literature.

EXPERT OPINION

Akin to its biliary drainage counterpart, EUS-PDD enables an EUS-assisted-ERP using rendezvous technique or EUS-guided drainage through transmural stenting. The technique has evolved over the ensuing years with multitude of accessories, approaches, and devices to optimize the outcomes. However, the technical success and adverse events rates need to be further improved. Additionally, it has a steep learning curve with requirements of advanced technical skill and optimum infrastructure back-up. Meticulous patient selection, precise knowledge of ductal anatomy, appropriate approach, and carefully chosen accessories can improve its clinical outcomes.

Impact of contrast-enhanced versus non-contrast computed tomography on acute kidney injury in acute necrotizing pancreatitis: A randomized controlled trial

BACKGROUND

The data evaluating contrast-induced-acute kidney injury (AKI) in patients with acute pancreatitis is scarce. This study aimed to compare the frequency of AKI in patients with acute necrotizing pancreatitis undergoing non-contrast computed tomography (NCCT) with those undergoing contrast-enhanced computed tomography (CECT) during hospitalization.

METHODS

This prospective randomized controlled trial (CTRI/2019/12/022206) screened consecutive patients with acute pancreatitis for eligibility and randomly allocated patients with acute necrotizing pancreatitis (based on CECT in the first week of illness) and normal renal functions to receive either NCCT or CECT during hospitalization. The incidence of development of new AKI and clinical outcomes was compared between the two groups. Post-hoc analysis was done to adjust for disease severity.

RESULTS

As many as 105 patients completed the study as per protocol (NCCT = 45 and CECT = 60). AKI occurred in 36 (34.3%) patients, nine (20%) in the NCCT and 27 (45%) in the CECT group. Contrast induced-AKI occurred in 11 (18.3%) patients, while 25 had AKI secondary to acute pancreatitis. The relative risk (RR) of AKI in the CECT group was 2.25 (95% CI 1.17-4.30, p = .0142). The frequency of intensive care unit (ICU) admission (RR = 2.1, 95% CI 1.34-3.27, p = .0001) and need for drainage of collections (RR = 1.39, 95% CI 1.1-1.7, p = .005) was significantly higher and the length of hospitalization (p = .001) and ICU admission (p = 0.001) were significantly longer in the CECT group. However, when adjusted for the severity of acute pancreatitis, there was no difference in AKI and clinical outcomes between the NCCT and CECT groups. The duration of AKI was significantly longer and the need for dialysis was significantly higher in patients who had AKI secondary to acute pancreatitis compared to those with contrast induced-AKI (p = .003).

CONCLUSION

CECT is not significantly associated with AKI in acute necrotizing pancreatitis.

Association between the Distribution of Adipose Tissue and Outcomes in Acute Pancreatitis: A Comparison of Methods of Fat Estimation

Purpose  To assess the correlation between abdominal fat measured at computed tomography (CT) and dual-energy X-ray absorptiometry (DXA) and association with clinical outcomes in patients with acute pancreatitis (AP). Methods  This prospective study comprised consecutive patients with AP who underwent abdominal CT and DXA. Fat estimation was done on whole-body DXA and abdominal CT. Correlations among body mass index (BMI), waist circumference (WC), DXA, and CT fat measurements were determined. The association between fat measurements and clinical outcomes was assessed. Results  Fifty-nine patients (mean age 38.2 years, 48 males) were included. There was a strong correlation ( r  = 0.691-0.799) between DXA and CT fat estimation. In addition, there was a significant association of the visceral adipose tissue (VAT) on DXA and CT with the severity of AP ( p  = 0.039 and 0.021, respectively) and the need for drainage of collections ( p  = 0.026 and 0.008, respectively). There was a weak correlation of the BMI and WC with the length of hospitalization (LOH) ( r  = 0.121, 0.190, respectively) and length of intensive care unit stay (LOICU) ( r  = 0.211, 0.197), while there was a moderate to strong correlation of the truncal fat and visceral fat on DXA and total adipose tissue and VAT on CT with LOH ( r  = 0.562, 0.532, 0.602 and 0.614, respectively) and LOICU ( r  = 0.591, 0.577, 0.636, and 0.676, respectively). Conclusion  In conclusion, fat indices measured on DXA and CT are associated with the severity of AP. In addition, the fat measurements at DXA are strongly correlated with those obtained at CT.

Evaluation of Inflammatory Infiltration in the Retroperitoneal Space of Acute Pancreatitis Using Computer Tomography and Its Correlation with Clinical Severity

This paper investigates the correlation between the degree and severity of CT inflammatory infiltration in the retroperitoneal space of acute pancreatitis (AP). A total of 113 patients were included based on diagnostic criteria. The general data of the patients and the relationship between the computed tomography severity index (CTSI) and pleural effusion (PE), involvement, degree of inflammatory infiltration of retroperitoneal space (RPS), number of peripancreatic effusion sites, and degree of pancreatic necrosis on contrast-enhanced CT at different times were studied. The results showed that the mean age of onset in females was later than that in males; 62 cases involved RPS to varying degrees, with a positive rate of 54.9% (62/113), and the total involvement rates of only the anterior pararenal space (APS); both APS and perirenal space (PS); and APS, PS, and posterior pararenal space (PPS) were 46.9% (53/113), 53.1% (60/113), and 17.7% (20/113), respectively. The degree of inflammatory infiltration in the RPS worsened with the increase in CTSI score; the incidence of PE was higher in the group greater than 48 hours than in the group less than 48 hours; necrosis >50% grade was predominant (43.2%) 5 to 6 days after onset, with a higher detection rate than other time periods (P < 0.05). Thus, when the PPS was involved, the patient's condition can be treated as severe acute pancreatitis (SAP); the higher the degree of inflammatory infiltration in the retroperitoneum, the higher the severity of AP. Enhanced CT examination 5 to 6 days after onset in patients with AP revealed the greatest extent of pancreatic necrosis.

Imaging of Mischievous Intra-abdominal Fat Presenting with Abdominal Pain: A Pictorial Review

Aim

To briefly discuss the imaging features of different types of intra-abdominal fat necrosis.

Background

Trauma and ischemic insult may result in intra-abdominal fat necrosis. Fat necrosis may present with acute abdomen, clinically simulating with other etiologies, such as acute diverticulitis and acute appendicitis.

Main body

Imaging plays a crucial role in making the exact diagnosis and differentiating it from other pathologies that may require surgical intervention. Computed tomography (CT) is the most commonly used imaging modality. A small fat attenuation lesion with a hyperattenuating rim in contact with the ventral surface of the sigmoid colon indicates epiploic appendagitis while a larger fat-attenuation lesion on the right side of the abdomen in between the colon and anterior abdominal wall indicates omental infarction. Fat stranding at the root of the mesentery with fat ring sign represents inflammatory mesenteric panniculitis while retractile or sclerosing mesenteritis appears as a fibrotic spiculated mass with or without calcification, mimicking mesenteric carcinoid. In patients with acute pancreatitis, the amount of inflamed fat correlates with clinical severity and outcome.

Conclusions

Familiarity with the imaging features of different types of intraabdominal fat necrosis helps in establishing an accurate diagnosis, thus avoiding unnecessary intervention.

How to cite this article

Patel RK, Mittal S, Singh S. Imaging of Mischievous Intra-abdominal Fat Presenting with Abdominal Pain: A Pictorial Review. Euroasian J Hepato-Gastroenterol 2022;12(1):45–49.

Effect of abdominal visceral fat on mortality risk in patients with severe acute pancreatitis

Background and Aim

Obesity is a well‐known risk factor for the development and severity of acute pancreatitis (AP), but the relationship between the abdominal visceral fat area (VFA) and mortality is unclear. We evaluated the effect of the VFA on mortality in severe AP (SAP).

Methods

This retrospective, single‐center cohort study examined 119 consecutive patients with SAP from April 2009 to March 2019. The VFA at the umbilical level was assessed using computed tomography. The primary endpoint was to evaluate whether visceral obesity affects mortality in SAP.

Results

The median age was 63 years, and 66% of participants were male. Nine patients (7.5%) died during their hospital stay. The median body mass index (BMI) was 22.2 kg/m², and six obese patients had a BMI of over 30 kg/m² (5%). The median waist circumference and VFA were 85.5 cm and 112 cm², respectively. Sixty‐eight (57.1%) patients had a VFA over 100 cm². The prognostic factor score based on the Japanese guidelines for AP management (cutoff value [COV], 4; area under the curve [AUC] = 0.869) and age [COV, 72; AUC = 0.780]) showed moderate accuracy for predicting mortality, followed by the VFA (COV, 167 cm²; AUC = 0.679). Univariate logistic analysis, but not multivariate analysis, showed that an increased VFA was associated with a significantly higher odds ratio (OR) for predicting mortality (OR: 4.38, P = 0.0406). The survival times of SAP patients with and without an increased VFA of 167 cm² were not significantly different.

Conclusions

Visceral obesity did not have a significant impact on predicting mortality in patients with SAP.

Unusual Sites of Necrotic Collections in Acute Necrotizing Pancreatitis: Association with Parenchymal Necrosis and Clinical Outcomes

BACKGROUND

The presence of necrotic collection in acute necrotizing pancreatitis (ANP) at intra-abdominal sites other than the retroperitoneum has not been systematically studied.

AIM

To investigate unusual sites of necrotic collections at computed tomography (CT) and to evaluate association with pancreatic necrosis and clinical outcomes.

METHODS

This retrospective study comprised of consecutive patients with ANP evaluated between January 2018 and March 2019. Based on CT findings, patients were divided into two groups: collections at unusual sites (small bowel mesentery, mesocolon, omentum, subcapsular collections along liver and spleen, pelvis, anterior abdominal wall, and inguinoscrotal regions) and collections at usual retroperitoneal locations (lesser sac, gastrosplenic location, anterior and posterior pararenal spaces, and paracolic gutters). The differences in CT findings and clinical outcomes (need for drainage, length of hospitalization, intensive care unit admission, surgery, and death) between the two groups were evaluated.

RESULTS

A total of 75 patients with ANP were evaluated. There were 25 (33.3%) patients with collections in unusual locations. These included mesentery (n = 17), splenic subcapsular location (n = 7), omentum (n = 6), hepatic subcapsular location (n = 4), anterior abdominal wall (n = 3), pelvis (n = 2), and inguinoscrotal location (n = 1). Compared to patients with collections at usual locations (n = 50), there were no differences in the CT findings except complete parenchymal necrosis (32% vs. 0%, P = .001). There were no statistically significant differences in the clinical outcomes between the two groups.

CONCLUSIONS

Mesenteric collections are frequent in ANP. The other non-retroperitoneal sites are infrequently involved. There is no association between unusual sites of collection and clinical outcomes.

The Effects of the Fat Distribution of Body, Skeletal Muscle Mass and Muscle Quality on Acute Pancreatitis Severity: A Retrospective Cross-Sectional Study

OBJECTIVE

We aim to investigate a possible relationship between acute pancreatitis (AP) and body fat and muscle parameters in computed tomography (CT).

METHODS

Computed tomography images of 107 patients with AP were scored in terms of AP severity using the modified CT severity index. Muscle mass, muscle mass index, visceral and subcutaneous adipose tissue area, multifidus muscle/fat attenuation ratio, total psoas index (TPI) and Hounsfield units average calculation (HUAC) values were performed.

RESULTS

Total psoas index and HUAC of mild AP cases were significantly higher than those with moderate and severe AP. The TPI of patients with severe pancreatic necrosis were found to be significantly lower than those without necrosis. Hounsfield units average calculation of cases without necrosis were significantly higher than those with severe necrosis in the pancreas.

CONCLUSIONS

Our study indicated that lower volume and density of psoas muscle associated with worse CT severity score and larger pancreatic necrosis in patients with AP.

Computed Tomography Findings in Intraabdominal Hypertension in Patients with Acute Pancreatitis

Purpose  Intraabdominal hypertension (IAH) in acute pancreatitis (AP) may reduce tissue perfusion and impair organ function and has been shown to portend poor prognosis. We investigated the computed tomography (CT) findings in patients with AP with IAH. Methods  This retrospective study comprised of consecutive patients with AP from June 2016 to June 2018 in whom intraabdominal pressure (IAP) was measured. The patients who underwent a contrast-enhanced CT within 7 days of IAP measurement were included. Using a cutoff of 12 mm Hg for IAP, the patients were divided into IAH and non-IAH groups. Measures of severity and clinical outcome were evaluated. CT parameters were compared between the groups. Results  The IAH group comprised of 41 patients, while there were 20 patients in the non-IAH group. The IAH group was characterized by severe disease, increased incidence of organ failure, increased requirement for drainage and surgery, prolonged hospital and intensive care unit stay. The mortality was not significantly different between the two groups. On univariate analysis, the CT features that were found to be significantly different between the two groups were the presence of collection ( p = 0.036), the maximum dimension of collection ( p = 0.004), volume of collection ( p = 0.019), biliary dilatation ( p = 0.011), and the presence of moderate-to-severe pleural effusion ( p = 0.009). On multivariate analysis, all these parameters except biliary dilatation were found to be statistically significant. Conclusion  CT findings in patients with AP may suggest IAH. This can be used as an additional marker for severity of AP.

Assessment of Computed Tomography-Defined Muscle and Adipose Tissue Features in Relation to Length of Hospital Stay and Recurrence of Hypertriglyceridemic Pancreatitis

Background

Analytic morphometric assessment has recently been proposed to be applied to the study of acute pancreatitis (AP). However, the relationship between body composition and the outcomes of hypertriglyceridemic pancreatitis (HTGP) is still unclear. The aim of this study was to evaluate body composition in relation to the length of hospital stay (LOS) and recurrence of HTGP.

Methods

Patient characteristics, admission examination data, body composition parameters, LOS, and recurrence within 1 year were collected from the institutional pancreatitis database and follow-up records. Logistic regression analysis was used to identify risk factors for LOS and recurrence of HTGP.

Results

Of the 196 included patients, 158 (80.6%) were men and 53 (27.0%) were sarcopenic. The average LOS was 15.83±10.02 days. The recurrence rate of HTGP was 36.7%. Multivariate analysis with multiple linear regression suggested that subcutaneous adipose tissue (SAT) area (p=0.019) and high-density lipoprotein-cholesterol (HDL-C) (p=0.001) were independently associated with the LOS for HTGP after adjusting for age and sex. The multivariate adjusted hazard ratios for SAT area and HDL-C, with respect to the relationship between body parameters and LOS, were 1.008 (95% confidence interval [CI], 1.001–1.015) and 0.090 (95% CI, 0.022–0.361), respectively. No significant differences were observed between the AP and recurrent AP (RAP) groups in terms of characteristics, admission examination data, and body composition parameters.

Conclusion

SAT area and HDL-C are associated with LOS in patients with HTGP. The body composition of patients at the first symptom onset of HTGP cannot predict recurrence.

Development and validation of a computed tomography index for assessing outcomes in patients with acute pancreatitis: "SMART-CT" index

PURPOSE

The existing CT indices do not allow quantitative prediction of clinical outcomes in acute pancreatitis (AP). The aim of this study was to develop and validate a revised CT index using a nomogram-based approach.

METHODS

This retrospective study comprised consecutive patients with AP who underwent contrast-enhanced CT between June 2017 and March 2019. 123 CT scans were randomly divided into training (n = 103) and validation groups (n = 20). Two radiologists analyzed CT scans for findings described in modified CT severity index and additional exploratory items (13 items). Seven items (pancreatic necrosis, number of collections, size of collections, ascites, pleural effusion, celiac artery involvement, and liver steatosis) found to be statistically significant were used for development of index. Synthetic minority oversampling technique (SMOTE) was employed to balance representation of minority classes and hence this index was named "SMOTE Application for Reading CT in AcuTe Pancreatitis (SMART-CT index)". Binomial logistic regression was used for development of prediction algorithm. Nomograms were then created and validated for each outcome.

RESULTS

The new CT index had area under the curve (AUC) of 0.79 [95% CI 0.65-0.93], 0.66 (95% CI 0.54-0.77), 0.75 (95% CI 0.65-0.85), 0.83 (95% CI 0.69-0.96), 0.70 (95% CI 0.60-0.81), and 0.64 (95% CI 0.53-0.75) for mortality, intensive care unit (ICU) stay, length of hospitalization, length of ICU stay, number of admissions, and severity, respectively. The AUC of validation cohort was comparable to the training cohort.

CONCLUSION

The novel nomogram-based index predicts occurrence of clinical outcome with moderate accuracy.

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.

Larger bore percutaneous catheter in necrotic pancreatic fluid collection is associated with better outcomes

OBJECTIVE

To evaluate the impact of initial catheter size on the clinical outcomes in acute pancreatitis (AP).

METHODS

This retrospective study comprised consecutive patients with AP who underwent percutaneous catheter drainage (PCD) between January 2018 and May 2019. Three hundred fifteen consecutive patients underwent PCD during the study period. Based on the initial catheter size, patients were divided into group I (≤ 12 F) and group II (> 12 F). The differences in the clinical outcomes between the two groups, as well as multiple subgroups (based on the severity, timing of drainage, and presence of organ failure (OF)), were evaluated.

RESULTS

One hundred forty-six patients (mean age, 41.2 years, 114 males) fulfilled the inclusion criteria. Ninety-nine (67.8%) patients had severe AP based on revised Atlanta classification. The mean pain to PCD was 22 days (range, 3-267 days). Mean length of hospitalization (LOH) was 27.9 ± 15.8 days. Necrosectomy was performed in 20.5% of patients, and mortality was 16.4%. Group I and II comprised 74 and 72 patients, respectively. There was no significant difference in baseline characteristics, except for a greater number of patients with OF in group II (p = 0.048). The intensive care unit stay was significantly shorter, and multiple readmissions were less frequent in group II (p = 0.037 and 0.013, respectively). Patients with severe AP and moderately severe AP in group II had significantly reduced rates of readmissions (p = 0.035) and significantly shorter LOH (p = 0.041), respectively.

CONCLUSION

Large-sized catheters were associated with better clinical outcomes regardless of disease severity and other baseline disease characteristics.

KEY POINTS

• Larger catheter size for initial PCD was associated with better clinical outcomes in AP. • The benefits were independent of the severity of AP, timing of PCD (ANC vs. WON) and presence of organ failure.

Interventional radiological management of hepatobiliary disorders in pregnancy

Hepatobiliary disorders are common in pregnancy and pose a management challenge. Minimally invasive interventional radiological (IR) techniques allow safe and effective management of these disorders. However, the available literature is scarce. Radiological interventions in this group of patients mandate a clear understanding of the risks of radiation to the fetus. The IR physician involved in the care of these patients should be aware of the measures to minimize the exposure to ionizing radiation. Additionally, the risk-benefit ratio should be clearly defined in a multidisciplinary discussion involving IR physicians, obstetricians, and gastroenterologists. This review is an effort to address issues related to the application of IR procedures for hepatobiliary disorders in pregnant patients.