Radiomics of Intrahepatic Cholangiocarcinoma and Peritumoral Tissue Predicts Postoperative Survival: Development of a CT-Based Clinical-Radiomic Model.

BACKGROUND: For many tumors, radiomics provided a relevant prognostic contribution. This study tested whether the computed tomography (CT)-based textural features of intrahepatic cholangiocarcinoma (ICC) and peritumoral tissue improve the prediction of survival after resection compared with the standard clinical indices. METHODS: All consecutive patients affected by ICC who underwent hepatectomy at six high-volume centers (2009-2019) were considered for the study. The arterial and portal phases of CT performed fewer than 60 days before surgery were analyzed. A manual segmentation of the tumor was performed (Tumor-VOI). A 5-mm volume expansion then was applied to identify the peritumoral tissue (Margin-VOI). RESULTS: The study enrolled 215 patients. After a median follow-up period of 28 months, the overall survival (OS) rate was 57.0%, and the progression-free survival (PFS) rate was 34.9% at 3 years. The clinical predictive model of OS had a C-index of 0.681. The addition of radiomic features led to a progressive improvement of performances (C-index of 0.71, including the portal Tumor-VOI, C-index of 0.752 including the portal Tumor- and Margin-VOI, C-index of 0.764, including all VOIs of the portal and arterial phases). The latter model combined clinical variables (CA19-9 and tumor pattern), tumor indices (density, homogeneity), margin data (kurtosis, compacity, shape), and GLRLM indices. The model had performance equivalent to that of the postoperative clinical model including the pathology data (C-index of 0.765). The same results were observed for PFS. CONCLUSIONS: The radiomics of ICC and peritumoral tissue extracted from preoperative CT improves the prediction of survival. Both the portal and arterial phases should be considered. Radiomic and clinical data are complementary and achieve a preoperative estimation of prognosis equivalent to that achieved in the postoperative setting.

Quantitative edge analysis of pancreatic margins in patients with head pancreatic tumors: correlations between pancreatic margins and the onset of postoperative pancreatic fistula.

OBJECTIVE: To assess the correlation between pancreatic quantitative edge analysis as a surrogate of parenchymal stiffness and the incidence of postoperative pancreatic fistula (POPF), in patients undergoing pancreaticoduodenectomy (PD). METHODS: All consecutive patients who underwent PD at our Institution between March 2018 and November 2019 with an available preoperative CT were included. Pancreatic margin score (PMS) was calculated through computer-assisted quantitative edge analysis on the margins of the pancreatic body and tail (the expected pancreatic remnant) on non-contrast scans with in-house software. Intraoperative assessment of pancreatic stiffness by manual palpation was also performed, classifying pancreatic texture into soft and non-soft. PMS values were compared between groups using an unpaired T-test and correlated with the intraoperative evaluation of stiffness and with the grading of postoperative pancreatic fistula according to the International Study Group on Pancreatic Surgery (ISGPS). RESULTS: Patient population included 200 patients (mean age 64.6 years), 146 without onset of POPF (73%, non-POPF group), and 54 with POPF (27%, POPF group). A significant difference in PMS values was observed between POPF and non-POPF (respectively 1.88 ± 0.05 vs 0.69 ± 0.01; p < 0.0001). PMS values of pancreatic parenchymas intraoperatively considered "soft" were significantly higher than those evaluated as "non-soft" (1.21 ± 0.04 vs 0.73 ± 0.02; p < 0.0001). A significant correlation between PMS values and POPF grade was observed (r = 0.8316), even in subgroups of patients with soft (r = 0.8016) and non-soft (r = 0.7602) pancreas (all p < 0.0001). CONCLUSIONS: Quantitative edge analysis with dedicated software may stratify patients with different pancreatic stiffness, thus potentially improving preoperative risk assessment and strategies for POPF mitigation. CLINICAL RELEVANCE STATEMENT: This study proposes quantitative pancreas edge analysis as a predictor for postoperative pancreatic fistula. The test has high accuracy and correlation with fistula grade according to the International Study Group on Pancreatic Surgery. KEY POINTS: • Prediction of postoperative pancreatic fistula (POPF) onset risk after pancreaticoduodenectomy is based only on intraoperative evaluation. • Quantitative edge analysis may preoperatively identify patients with higher risk of POPF. • Quantification of pancreatic stiffness through the analysis of pancreatic margins could be done on preoperative CT.

A European Society of Oncologic Imaging (ESOI) survey on the radiological assessment of response to oncologic treatments in clinical practice.

OBJECTIVES: To present the results of a survey on the assessment of treatment response with imaging in oncologic patient, in routine clinical practice. The survey was promoted by the European Society of Oncologic Imaging to gather information for the development of reporting models and recommendations. METHODS: The survey was launched on the European Society of Oncologic Imaging website and was available for 3 weeks. It consisted of 5 sections, including 24 questions related to the following topics: demographic and professional information, methods for lesion measurement, how to deal with diminutive lesions, how to report baseline and follow-up examinations, which previous studies should be used for comparison, and role of RECIST 1.1 criteria in the daily clinical practice. RESULTS: A total of 286 responses were received. Most responders followed the RECIST 1.1 recommendations for the measurement of target lesions and lymph nodes and for the assessment of tumor response. To assess response, 48.6% used previous and/or best response study in addition to baseline, 25.2% included the evaluation of all main time points, and 35% used as the reference only the previous study. A considerable number of responders used RECIST 1.1 criteria in daily clinical practice (41.6%) or thought that they should be always applied (60.8%). CONCLUSION: Since standardized criteria are mainly a prerogative of clinical trials, in daily routine, reporting strategies are left to radiologists and oncologists, which may issue local and diversified recommendations. The survey emphasizes the need for more generally applicable rules for response assessment in clinical practice. CRITICAL RELEVANCE STATEMENT: Compared to clinical trials which use specific criteria to evaluate response to oncological treatments, the free narrative report usually adopted in daily clinical practice may lack clarity and useful information, and therefore, more structured approaches are needed. KEY POINTS: · Most radiologists consider standardized reporting strategies essential for an objective assessment of tumor response in clinical practice. · Radiologists increasingly rely on RECIST 1.1 in their daily clinical practice. · Treatment response evaluation should require a complete analysis of all imaging time points and not only of the last.

Quantitative Edge Analysis of Pancreatic Margins in Patients with Chronic Pancreatitis: A Correlation with Exocrine Function.

BACKGROUND: Many efforts have been made to improve accuracy and sensitivity in diagnosing chronic pancreatitis (CP), obtaining quantitative assessments related to functional data. Our purpose was to correlate a computer-assisted analysis of pancreatic morphology, focusing on glandular margins, with exocrine function-measured by fecal elastase values-in chronic pancreatitis patients. METHODS: We retrospectively reviewed chronic pancreatitis patients who underwent fecal elastase assessment and abdominal MRI in our institute within 1 year. We identified 123 patients divided into three groups based on the fecal elastase value: group A with fecal elastase > 200 µg/g; group B with fecal elastase between 100 and 200 µg/g; and group C with fecal elastase < 100 µg/g. Computer-assisted quantitative edge analysis of pancreatic margins was made on non-contrast-enhanced water-only Dixon T1-weighted images, obtaining the pancreatic margin score (PMS). PMS values were compared across groups using a Kruskal-Wallis test and the correlation between PMS and fecal elastase values was tested with the Spearman's test. RESULTS: A significant difference in PMS was observed between the three groups (p < 0.0001), with a significant correlation between PMS and elastase values (r = 0.6080). CONCLUSIONS: Quantitative edge analysis may stratify chronic pancreatitis patients according to the degree of exocrine insufficiency, potentially contributing to the morphological and functional staging of this pathology.

The Spectrum of Solitary Benign Splenic Lesions-Imaging Clues for a Noninvasive Diagnosis.

Cross-sectional imaging of the upper abdomen, especially if intravenous contrast has been administered, will most likely reveal any acute or chronic disease harbored in the spleen. Unless imaging is performed with the specific purpose of evaluating the spleen or characterizing a known splenic lesion, incidentally discovered splenic lesions pose a small challenge. Solitary benign splenic lesions include cysts, hemangiomas, sclerosing angiomatous nodular transformation (SANT), hamartomas, and abscesses, among others. Sarcoidosis and tuberculosis, although predominantly diffuse micronodular disease processes, may also present as a solitary splenic mass lesion. In addition, infarction and rupture, both traumatic and spontaneous, may take place in the spleen. This review aims to describe the imaging features of the most common benign focal splenic lesions, with emphasis on the imaging findings as these are encountered on routine cross-sectional imaging from a multicenter pool of cases that, coupled with clinical information, can allow a definite diagnosis.

Imaging of paraduodenal pancreatitis: A systematic review.

BACKGROUND: Paraduodenal pancreatitis (PP) represents a diagnostic challenge, especially in non-referral centers, given its potential imaging overlap with pancreatic cancer. There are two main histological variants of PP, the cystic and the solid, with slightly different imaging appearances. Moreover, imaging findings in PP may change over time because of disease progression and/or as an effect of its risk factors exposition, namely alcohol intake and smoking. AIM: To describe multimodality imaging findings in patients affected by PP to help clinicians in the differential diagnosis with pancreatic cancer. METHODS: The systematic review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-analyses 2009 guidelines. A Literature search was performed on PubMed, Embase and Cochrane Library using (groove pancreatitis [Title/Abstract]) OR (PP [Title/Abstract]) as key words. A total of 593 articles were considered for inclusion. After eliminating duplicates, and title and abstract screening, 53 full-text articles were assessed for eligibility. Eligibility criteria were: Original studies including 8 or more patients, fully written in English, describing imaging findings in PP, with pathological confirmation or clinical-radiological follow-up as the gold standard. Finally, 14 studies were included in our systematic review. RESULTS: Computed tomography (CT) findings were described in 292 patients, magnetic resonance imaging (MRI) findings in 231 and endoscopic ultrasound (EUS) findings in 115. Duodenal wall thickening was observed in 88.8% of the cases: Detection rate was 96.5% at EUS, 91.0% at MRI and 84.1% at CT. Second duodenal portion increased enhancement was recognizable in 76.3% of the cases: Detection rate was 84.4% at MRI and 72.1% at CT. Cysts within the duodenal wall were detected in 82.6% of the cases: Detection rate was 94.4% at EUS, 81.9% at MRI and 75.7% at CT. A solid mass in the groove region was described in 40.9% of the cases; in 78.3% of the cases, it showed patchy enhancement in the portal venous phase, and in 100% appeared iso/hyperintense during delayed phase imaging. Only 3.6% of the lesions showed restricted diffusion. The prevalence of radiological signs of chronic obstructive pancreatitis, namely main pancreatic duct dilatation, pancreatic calcifications, and pancreatic cysts, was extremely variable in the different articles. CONCLUSION: PP has peculiar imaging findings. MRI is the best radiological imaging modality for diagnosing PP, but EUS is more accurate than MRI in depicting duodenal wall alterations.

Epicardial adipose tissue volume and CT-attenuation as prognostic factors for pulmonary embolism and mortality in critically ill patients affected by COVID-19.

BACKGROUND/OBJECTIVES: The aim of this post-hoc analysis was to evaluate if epicardial adipose tissue (EAT) quantity and quality, as evaluated by computed tomography (CT), have a different role in the risk of mortality and pulmonary embolism in critically ill COVID-19 patients admitted to an intensive care unit (ICU). SUBJECTS/METHODS: CT derived EAT volume and density, as well as anthropometric and blood biomarkers, were evaluated in a sample of 138 subjects, 109 men and 29 women, for whom CT images and information on pulmonary embolism were available from a total of 313 subjects who were consecutively admitted to the ICU for COVID-19 from the REINSURE-ARDS prospective registry. RESULTS: A total of 28 patients (20.3%) died during the first 28 days after ICU admission. 26 subjects out of 138 had pulmonary embolism (18.8%). Age, weight, BMI, IL-6 levels and pulmonary embolism prevalence were significantly higher across EAT volume tertiles. Subjects who died in the first 28 days from ICU admission were older, had higher EAT volume, D-dimer, LDH and IL-6 level. After adjustment for age and gender, participants in tertile 3 of EAT volume had lower survival at 28 days from ICU admission as compared to subjects in the tertile 1, HR 2.95 (95% C.I. 1.02-8.49), but after adjusting for potential confounders the relation was no longer significant. No relation between EAT density and mortality was observed. From a binary logistic regression, subjects in tertile 3 of EAT volume and in tertile 1 of EAT density showed a 4 times and 3.6 times increased risk of pulmonary embolism, respectively. CONCLUSIONS: ICU subjects affected by severe COVID-19 with higher EAT volume and low EAT density should be carefully monitored and managed with a prompt and aggressive approach, to prevent serious and life-threatening consequences and the increase of hospital treatment costs.

Attitudes and perceptions of radiologists towards online (virtual) oncologic multidisciplinary team meetings during the COVID-19 pandemic-a survey of the European Society of Oncologic Imaging (ESOI).

OBJECTIVES: To explore radiologists' opinions regarding the shift from in-person oncologic multidisciplinary team meetings (MDTMs) to online MDTMs. To assess the perceived impact of online MDTMs, and to evaluate clinical and technical aspects of online meetings. METHODS: An online questionnaire including 24 questions was e-mailed to all European Society of Oncologic Imaging (ESOI) members. Questions targeted the structure and efficacy of online MDTMs, including benefits and limitations. RESULTS: A total of 204 radiologists responded to the survey. Responses were evaluated using descriptive statistical analysis. The majority (157/204; 77%) reported a shift to online MDTMs at the start of the pandemic. For the most part, this transition had a positive effect on maintaining and improving attendance. The majority of participants reported that online MDTMs provide the same clinical standard as in-person meetings, and that interdisciplinary discussion and review of imaging data were not hindered. Seventy three of 204 (35.8%) participants favour reverting to in-person MDTs, once safe to do so, while 7/204 (3.4%) prefer a continuation of online MDTMs. The majority (124/204, 60.8%) prefer a combination of physical and online MDTMs. CONCLUSIONS: Online MDTMs are a viable alternative to in-person meetings enabling continued timely high-quality provision of care with maintained coordination between specialties. They were accepted by the majority of surveyed radiologists who also favoured their continuation after the pandemic, preferably in combination with in-person meetings. An awareness of communication issues particular to online meetings is important. Training, improved software, and availability of support are essential to overcome technical and IT difficulties reported by participants. KEY POINTS: • Majority of surveyed radiologists reported shift from in-person to online oncologic MDT meetings during the COVID-19 pandemic. • The shift to online MDTMs was feasible and generally accepted by the radiologists surveyed with the majority reporting that online MDTMs provide the same clinical standard as in-person meetings. • Most would favour the return to in-person MDTMs but would also accept the continued use of online MDTMs following the end of the current pandemic.

Sarcobesity Index Predicts Poor Disease-Specific Survival After Resection for Colorectal Cancer.

INTRODUCTION: Sarcobesity (SO) is traditionally defined as the association between low muscle mass and obesity and has been reported to worsen prognosis after curative resection for colorectal cancer (CRC). This study aimed to propose a new definition of SO based on computed tomography measurements of the skeletal muscle area (SMA) and visceral adipose tissue (VAT) and to assess its implications on long-term survival after curative resection for stage I-III CRC. METHODS: We retrospectively analyzed 506 patients with stage I-III CRC who underwent surgery between January 2010 and December 2019. Preoperative computed tomography images were analyzed and the sarcobesity index (SI) was calculated for each patient as the VAT/SMA ratio. The optimal cutoff value for predicting survival was determined using time-dependent receiver operating characteristic analysis. Overall survival and disease-specific survival (DSS) were compared between SO (SI > 1.25) and non-SO (SI ≤ 1.25) patients. The rates and modes of recurrence were also compared between the two groups. RESULTS: Three hundred (59.3%) patients were identified to be sarcobese. No differences in short-term outcomes and administration of adjuvant chemotherapy were found, except for a longer length of stay in patients with SO. In a univariable analysis, SO was associated with a worse 5-y overall survival and DSS, considering the whole population and stages II and III separately. A multivariable analysis confirmed SO to be an independent risk factor for DSS (hazard ratio 2.29; 95% confidence interval 1.13-4.62, P = 0.02). Although the overall recurrence rate did not differ between the groups, a significantly higher rate of recurrence at multiple sites was observed in patients with SO (P = 0.01). CONCLUSIONS: The SI, defined as per the VAT/SMA ratio, seems to be a reliable tool for identifying patients with worse DSS after potentially curative surgery for stage I-III CRC.

Visceral obesity enhances inflammatory response after laparoscopic colorectal resection.

AIMS: C-reactive protein (CRP) is used for monitoring postoperative inflammation (POI) and detecting infectious complications. The aim of this study was to assess the effect of visceral obesity (VO) on acute POI measured through CRP after elective laparoscopic colorectal resection. METHODS: Pre-operative Computed tomography images of 357 patients who underwent laparoscopic colorectal resection were analyzed. Visceral adipose tissue (VAT) area was measured for each patient. VO was defined as VAT area >163.8 cm2 in men and >80.1 cm2 in women according to accepted sex-specific cut-offs. Postoperative outcomes and CRP values were compared between VO and non-VO groups. The most appropriate CRP value for identifying infectious complications in the two groups was assessed with receiver operating characteristic (ROC) curves. Univariate and multivariate analyses were conducted for factors affecting POI including VO. RESULTS: No differences in postoperative outcomes and infectious complications were found in VO patients (62.2% of the overall population). Both in the overall cohort and in patients without infectious complications, VO was associated with higher CRP values on postoperative day (POD) 1, POD2, POD3, and POD5. A positive correlation was found between VAT and CRP on all PODs. VO independently predicted higher CRP on POD1-3 in patients without infectious complications but not in those who developed complications. ROC curves analysis showed optimal accuracy for detection of infectious complications for CRP on POD3 in both groups, though the optimal cut-off value was higher in VO group (154 vs 136 mg/L). CONCLUSIONS: VO is not associated to increased complications after laparoscopic colorectal resection. Nevertheless, it is independently associated to higher CRP in the overall population and in patients without infectious complications. Consequently, CRP values on POD3 higher than cut-offs commonly adopted in the clinical practice should be carefully evaluated in VO patients to assess the occurrence of infectious complications.

Intermuscular Adipose Tissue as a Risk Factor for Mortality and Muscle Injury in Critically Ill Patients Affected by COVID-19.

BACKGROUND: Muscular fatigue and injury are frequently observed in critically ill COVID-19 patients. The aim of this study was to determine whether different muscle adipose tissue depots are associated with mortality and muscle damage in patients affected by COVID-19 admitted to the ICU. METHODS: CT images were obtained in 153 ICU patients with COVID-19 (121 males and 32 females). Height, weight, body mass index (BMI), C-reactive protein, Creatine PhosphoKinase (CPK), muscle density, and intermuscular adipose tissue (IMAT) were measured. RESULTS: Participants in the highest tertile of IMAT/muscle had the shorter 28-day survival from ICU admission as compared to subjects in the first tertile. Estimates derived from the Cox proportional hazard models, after adjustment for age, sex, and BMI, confirmed the results of the survival analysis (HR 3.94, 95% CI: 1.03-15.09). Participants in the lowest tertile of muscle density had the shorter survival at 28 days from ICU admission as compared to subjects in the highest tertile (HR 3.27, 95% CI: 1.18-4.61), but the relationship was no longer significant when age was included in the model. Subjects in the second muscle density tertile did not show an increased risk.Participants in the highest tertile of IMAT/muscle and those in the lowest tertile of muscle density showed both significantly higher CPK adjusted for weight values as evaluated during the first 8 days of hospitalization. CONCLUSION: Our data seem to suggest that higher levels of IMAT/muscle and low muscle density are both associated with higher risk of ICU mortality and muscle injury as evaluated with CPK level.

Accuracy of unenhanced CT in the diagnosis of cerebral venous sinus thrombosis.

OBJECTIVES: To evaluate the diagnostic performance of unenhanced brain CT (NECT) in identifying patients with cerebral venous sinus thrombosis (CVT). METHODS: Forty-eight consecutive patients with CVT and 48 healthy controls were included in our retrospective study. All patients underwent NECT and CT/MR angiography within 24 h. Two radiologists independently evaluated NECT images for the presence of sinus hyperdensity; discrepancies were solved by consensus. Sinus attenuation was measured in seven sites. The obtained data were compared with the presence of CVT at CT/MR angiography and with patients' hematocrit. RESULTS: Interobserver agreement in sinus hyperdensity detection was good (k = 0.64). The presence of sinus hyperdensity at NECT enabled to detect patients with CVT with 81% sensitivity, 77% specificity, 78% PPV, and 80% NPV. Mean attenuation was significantly higher in sinus segments involved by CVT than in patent ones (62.4 ± 10 versus 55.6 ± 6 HU, p < 0.0001). ROC analysis showed that a cutoff value of 63 HU enables to detect patients with CVT with 52% sensitivity and 88% specificity. Hematocrit values were significantly correlated with patent sinus segments attenuation (r = 0.19). CONCLUSIONS: The presence of sinus hyperdensity at NECT enables to detect patients with CVT with 81% sensitivity and 77% specificity. A sinus attenuation cutoff value of 63 HU can be used in order to increase specificity, but lowering sensitivity.

Liver enhancement during hepatobiliary phase after Gd-BOPTA administration: correlation with liver and renal function.

OBJECTIVES: To assess the influence of liver and renal function on liver relative enhancement during hepatobiliary phase MRI after Gd-BOPTA administration. METHODS: In this IRB-approved retrospective cohort study, we included 326 patients who underwent Gd-BOPTA-enhanced 1.5T liver MRI, including hepatobiliary phase (HBP) acquired 90-150 min after injection, in two centres between Jan 2016 and Dec 2019. Liver signal intensity was measured on native and HBP phases and normalized to paraspinal muscles. Liver normalized relative enhancement (NRE) in HBP was calculated and compared with eGFR, total serum bilirubin and HBP acquisition delay by means of Spearman r correlation test and Mann-Whitney U test. RESULTS: 221/326 patients received 0.05 mmol/Kg Gd-BOPTA (group A), whereas 105/326 received 0.1 mmol/Kg (group B). Liver NRE in HBP was significantly higher in group B than in group A (0.55vs.0.33, p < 0.0001). In both groups, liver NRE in HBP had a negative correlation with total serum bilirubin level (r = - 0.32, p < 0.0001, group A; r = - 0.36, p = 0.0002, group B). Patients with total bilirubin > 1.2 mg/dl showed significantly lower NRE in HBP compared with those with total bilirubin ≤ 1.2 mg/dl (p < 0.0001, group A; p = 0.04, group B). Patients with impaired liver function in group B showed a NRE during HBP comparable with those with normal liver function in group A. No statistically significant correlation between liver NRE and eGFR or acquisition delay was observed. CONCLUSIONS: The degree of liver enhancement during HBP is not correlated with eGFR or acquisition delay, but it is significantly reduced in patients with impaired liver function. 0.1 mmol/kg Gd-BOPTA dose might be useful in patients with total serum bilirubin > 1.2 mg/dl. KEY POINTS: • The degree of liver enhancement during hepatobiliary phase after Gd-BOPTA administration has a negative correlation with total serum bilirubin level (r = - 0.32, p < 0.0001). • The degree of liver enhancement during HBP after Gd-BOPTA administration is not significantly correlated with renal function and acquisition delay (comprised between 90 and 150 min after contrast injection). • 0.1 mmol/Kg Gd-BOPTA dose might be preferable in patients with increased total serum bilirubin levels.

Cytomegalovirus-Induced Gastrointestinal Bleeding and Pancreatitis Complicating Severe Covid-19 Pneumonia: A Paradigmatic Case.

COVID-19 is a new pandemic disease whose pathophysiology and clinical description are still not completely defined. Besides respiratory symptoms and fever, gastrointestinal (GI) symptoms (including especially anorexia, diarrhea, and abdominal pain) represent the most frequent clinical manifestations. Emerging data point out that severe SARS-CoV-2 infection causes an immune dysregulation, which in turn may favor other infections. Here we describe a patient with severe COVID-19 pneumonia who developed in the resolving phase abdominal pain associated with cytomegalovirus (CMV)-induced duodenitis with bleeding and pancreatitis. A high level of suspicion toward multiple infections, including CMV, should be maintained in COVID-19 patients with heterogeneous clinical manifestations.

Dislocation of intra-abdominal drains after pancreatic surgery: results of a prospective observational study.

PURPOSE: The use of intra-abdominal drains after major surgical procedures represents a well-established but controversial practice. No data are available regarding both the occurrence and the potential impact of their postoperative accidental dislocation. The aim of this study is to assess the actual rate of dislocation of intra-abdominal drains postoperatively and to evaluate its clinical impact. METHODS: This is a prospective observational study using major pancreatic surgery as a model. Ninety-one consecutive patients undergoing pancreatoduodenectomy (PD) or distal pancreatectomy (DP) underwent low-dose, non-enhanced computed tomography (LDCT) on postoperative days (POD) 1 and 3 in a blinded fashion to assess the position of drains. We compared the outcomes of patients with dislocated and correctly placed drains. RESULTS: Overall, drains were dislocated in 30 patients (33%), without differences between PD and DP. Most of dislocations were already present on POD 1 (77%). Postoperative complications occurred in 57% of patients, and the rate of postoperative pancreatic fistula (POPF) was 27%. The dislocated cohort had lesser morbidity (40% vs. 66%; relative risk (RR), 0.35; 95% CI, 0.14-0.86; P = 0.020), and the rate of POPF (3% vs. 39%, respectively; RR, 0.05; 95% CI, 0.01-0.42; P < 0.001). After PD, patients with dislocated drains had a shorter hospital stay (12 vs. 20 days; P = 0.015). No significant differences in terms of need for percutaneous drainage procedures, abdominal collections, or grade C POPFs were found between the groups. CONCLUSIONS: Dislocation of intra-abdominal drains is an early and frequent event after major pancreatic resection. Its occurrence might protect against the negative effects of maintaining drainage, eventually leading to better postoperative outcomes. This data reinforces the knowledge that surgical drains might be detrimental in selected cases.

Ascites relative enhancement during hepatobiliary phase after Gd-BOPTA administration: a new promising tool for characterising abdominal free fluid of unknown origin.

OBJECTIVES: To correlate the degree of ascites enhancement during hepatobiliary phase after gadobenate dimeglumine (Gd-BOPTA) administration with ascites aetiology. METHODS: IRB-approved retrospective study, need for informed consent was waived. We included 74 consecutive ascitic patients who underwent Gd-BOPTA-enhanced liver MRI including hepatobiliary phase (HBP) images between January 2014 and December 2017. Ascites appearance on unenhanced and HBP images was classified as hypo-, iso- or hyperintense in comparison to paraspinal muscles. Ascites signal intensity on unenhanced and HBP images was measured using round ROIs and was normalised to paraspinal muscles (NSI). Normalised relative enhancement (NRE) between native phase and HBP was calculated. The results were related to ascites aetiology using Wilcoxon and Mann-Whitney tests. RESULTS: On native images, ascites appeared hypointense in 95.9% of the cases and isointense in 4.1%, whereas on HBP images, it appeared hyperintense in 59.4% of the cases, isointense in 36.5% and hypointense in 4.1%. Mean ascites NSI was 0.52 on unenhanced images and 1.50 on HBP ones (p < 0.0001). Mean ascites NRE was 201 ± 133%. Ascites of non-malignant aetiology showed mean NRE of 210 ± 134%, whereas malignant ascites showed mean NRE of 92 ± 20% (p = 0.001). ROC analysis showed that a NRE < 112.5% correlates with malignant aetiology with 100% sensitivity and 83.4% specificity (LR = 5.667). NRE did not show any significant correlation with ascites thickness, eGFR and time interval between contrast administration and HBP acquisition (p > 0.05). CONCLUSIONS: Ascites NRE in HBP after Gd-BOPTA administration is significantly lower in patients with ascites secondary to peritoneal carcinomatosis than in patients with non-malignant ascites. KEY POINTS: • Ascites enhancement in the hepatobiliary phase after Gd-BOPTA administration may determine false positive findings when looking for biliary leaks. • Ascites enhancement in the hepatobiliary phase after Gd-BOPTA administration is lower in patients with peritoneal carcinomatosis than in patients with portal hypertension or congestive heart failure. • None of the patients with peritoneal carcinomatosis showed an ascites enhancement of more than 112% as compared with unenhanced images.

Type 1 and Type 2 Autoimmune Pancreatitis: Distinctive Clinical and Pathological Features, But Are There Any Differences at Magnetic Resonance? Experience From a Referral Center.

OBJECTIVES: This study aimed to evaluate magnetic resonance imaging findings of autoimmune pancreatitis (AIP) and to find radiological patterns that could differentiate type 1 and type 2 AIP. METHODS: Eighty-four patients with diagnosis of AIP were enrolled. Image analysis included pancreatic signal intensity abnormalities, enhancement pattern, extrapancreatic involvement, and main pancreatic duct alterations. RESULTS: Pancreatic parenchyma resulted in hypointensity on T1-weighted images in 65 (98.5%) of 66 cases in type 1 and in 17 (94.5%) of 18 in type 2 (P > 0.05) and in hyperintensity on T2-weighted images in 41 (62%) of 66 and in 15 (83.4%) of 18, respectively (P > 0.05). Lesions were hypovascular in 64 (97%) of 66 cases in type 1 and in 16 (88.9%) of 18 in type 2 with delayed contrast retention in 56 (84.8%) of 66 and in 17 (94.5%) of 18, respectively (P > 0.05). Autoimmune cholangitis was found in 29 (43.9%) of 66 patients with type 1 and in 3 (16.7%) of 18 with type 2 (P = 0.02); renal involvement was observed in 20 (30.3%) of 66 and 1 (5.5%) of 18, respectively (P = 0.02). Both subtypes presented with multiple stenoses (P > 0.05). Dilation of upstream duct was more frequent in type 1 (P = 0.02). CONCLUSIONS: Magnetic resonance imaging is useful in detecting extrapancreatic involvement, typically seen in type 1. Dilation of the upstream duct suggests type 1 AIP.

Major pancreatic resections: normal postoperative findings and complications.

OBJECTIVES: (1) To illustrate and describe the main types of pancreatic surgery; (2) to discuss the normal findings after pancreatic surgery; (3) to review the main complications and their radiological findings. BACKGROUND: Despite the decreased postoperative mortality, morbidity still remains high resulting in longer hospitalisations and greater costs. Imaging findings following major pancreatic resections can be broadly divided into "normal postoperative alterations" and real complications. The former should regress within a few months whereas complications may be life-threatening and should be promptly identified and treated. IMAGING FINDINGS: CT is the most effective postoperative imaging technique. MRI and fluoroscopy are used less often and only in specific cases such as assessing the gastro-intestinal function or the biliary tree. The most common normal postoperative findings are pneumobilia, perivascular cuffing, fluid collections, lymphadenopathy, acute anastomotic oedema and stranding of the peri-pancreatic/mesenteric fat. Imaging depicts the anastomoses and the new postoperative anatomy. It can also demonstrate early and late complications: pancreatic fistula, haemorrhage, delayed gastric emptying, hepatic infarction, acute pancreatitis of the remnant, porto-mesenteric thrombosis, abscess, biliary anastomotic leaks, anastomotic stenosis and local recurrence. CONCLUSIONS: Radiologists should be aware of surgical procedures, postoperative anatomy and normal postoperative imaging findings to better detect complications and recurrent disease. TEACHING POINTS: • Morbidity after pancreatic resections is high. • CT is the most effective postoperative imaging technique. • Imaging depicts the anastomoses and the new postoperative anatomy. • Pancreatic fistula is the most common complication after partial pancreatic resection.