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The discontinuous peripheral enhancement is a pattern of enhancement usually attributed to typical cavernous hemangioma, that is the most common benign solid lesion of the liver. The discontinuous peripheral enhancement, however, may be encountered in many other benign and malignant focal liver lesions as an atypical presentation or evolution, and hemangiomas with discontinuous peripheral hyperenhancement on hepatic arterial phase may not always have the typical post-contrast pattern on portal venous and delayed phases. Therefore, abdominal radiologists may be challenged in their practice by lesions with discontinuous peripheral enhancement. This pictorial essay aims to review the spectrum of benign and malignant focal liver lesions that may show discontinuous peripheral enhancement. A particular point of interest is the diagnostic tree pathway that may guide the radiologists in the differential diagnosis., (© 2024. The Author(s).)

Rim arterial phase hyperenhancement is an imaging feature commonly encountered on contrast-enhanced CT and MRI in focal liver lesions. Rim arterial phase hyperenhancement is a subtype of arterial phase hyperenhancement mainly present at the periphery of lesions on the arterial phase. It is caused by a relative arterialization of the periphery compared with the center of the lesion and needs to be differentiated from other patterns of peripheral enhancement, including the peripheral discontinuous nodular enhancement and the corona enhancement. Rim arterial phase hyperenhancement may be a typical or an atypical imaging presentation of many benign and malignant focal liver lesions, challenging the radiologists during imaging interpretation. Benign focal liver lesions that may show rim arterial phase hyperenhancement may have a vascular, infectious, or inflammatory origin. Malignant focal liver lesions displaying rim arterial phase hyperenhancement may have a vascular, hepatocellular, biliary, lymphoid, or secondary origin. The differences in imaging characteristics on contrast-enhanced CT may be subtle, and a multiparametric approach on MRI may be helpful to narrow the list of differentials. This article aims to review the broad spectrum of focal liver lesions that may show rim arterial phase hyperenhancement, using an approach based on the benign and malignant nature of lesions and their histologic origin. CRITICAL RELEVANCE STATEMENT: Rim arterial phase hyperenhancement may be an imaging feature encountered in benign and malignant focal liver lesions and the diagnostic algorithm approach provided in this educational review may guide toward the final diagnosis. KEY POINTS: Several focal liver lesions may demonstrate rim arterial phase hyperenhancement. Rim arterial phase hyperenhancement may occur in vascular, inflammatory, and neoplastic lesions. Rim arterial phase hyperenhancement may challenge radiologists during image interpretation., (© 2024. The Author(s).)

Liver diseases in pregnancy can be specific to gestation or only coincidental. In the latter case, the diagnosis can be difficult. Rapid diagnosis of maternal-fetal emergencies and situations requiring specialized interventions are crucial to preserve the maternal liver and guarantee materno-fetal survival. While detailed questioning of the patient and a clinical examination are highly important, imaging is often essential to reach a diagnosis of these liver diseases and lesions. Three groups of liver diseases may be observed during pregnancy: (1) diseases related to pregnancy: intrahepatic cholestasis of pregnancy, pre-eclampsia, eclampsia, hemolysis, elevated liver enzymes and low platelets (HELLP) syndrome, and acute fatty liver of pregnancy; (2) liver diseases that are more frequent during or exacerbated by pregnancy: acute herpes simplex hepatitis, Budd-Chiari syndrome, hemorrhagic hereditary telangiectasia, hepatocellular adenoma, portal vein thrombosis, and cholelithiasis; (3) coincidental conditions, including acute hepatitis, incidental focal liver lesions, metabolic dysfunction-associated steatotic liver disease, cirrhosis, hepatocellular carcinoma, liver abscesses and parasitosis, and liver transplantation. Specific knowledge of the main imaging findings is required to reach an early diagnosis, for adequate follow-up, and to avoid adverse consequences in both the mother and the fetus.Critical relevance statement Pregnancy-related liver diseases are the most important cause of liver dysfunction in pregnant patients and, in pregnancy, even common liver conditions can have an unexpected turn. Fear of radiations should never delay necessary imaging studies in pregnancy.Key points• Pregnancy-related liver diseases are the most frequent cause of liver dysfunction during gestation.• Fear of radiation should never delay necessary imaging studies.• Liver imaging is important to assess liver emergencies and for the diagnosis and follow-up of any other liver diseases.• Common liver conditions and lesions may take an unexpected turn during pregnancy.• Pregnancy-specific diseases such as pre-eclampsia and HELLP syndrome must be rapidly identified. However, imaging should never delay delivery when it is considered to be urgent for maternal-fetal survival., (© 2024. The Author(s).)

Background: Data about reperfusion injury (RI) following acute arterial mesenteric ischemia (AAMI) in humans are scarce. We aimed to assess the prevalence and risk factors of RI following endovascular revascularization of AMI and evaluate its impact on patient outcomes., Methods: Patients with AAMI who underwent endovascular revascularization (2016-2021) were included in this retrospective cohort. CT performed < 7 days after treatment was reviewed to identify features of RI (bowel wall hypoattenuation, mucosal hyperenhancement). Clinical, laboratory, imaging, and treatments were compared between RI and non-RI patients to identify factors associated with RI. Resection rate and survival were also compared., Results: Fifty patients (23 men, median 72-yrs [IQR 60-77]) were included, and 22 were diagnosed with RI (44%) after a median 28 h (22-48). Bowel wall hypoattenuation and mucosal hyperenhancement were found in 95% and 91% of patients with post-interventional RI, respectively. Patients with RI had a greater increase of CRP levels after endovascular treatment (p = 0.01). On multivariate analysis, a decreased bowel wall enhancement on baseline CT (HR = 8.2), an embolic cause (HR = 7.4), complete SMA occlusion (HR = 7.0), and higher serum lactate levels (HR = 1.4) were associated with RI. The three-month survival rate was 78%, with no difference between subgroups (p = 0.99). However, the resection rate was higher in patients with RI (32% versus 7%; p = 0.03)., Conclusion: RI is frequent after endovascular revascularization of AAMI, especially in patients who present with decreased bowel wall enhancement on pre-treatment CT, an embolic cause, and a complete occlusion of the SMA. However, its occurrence does not seem to negatively impact short-term survival., (© 2022. The Author(s).)

Chronic liver diseases, resulting from chronic injuries of various causes, lead to cirrhosis with life-threatening complications including liver failure, portal hypertension, hepatocellular carcinoma. A key unmet medical need is robust non-invasive biomarkers to predict patient outcome, stratify patients for risk of disease progression and monitor response to emerging therapies. Quantitative imaging biomarkers have already been developed, for instance, liver elastography for staging fibrosis or proton density fat fraction on magnetic resonance imaging for liver steatosis. Yet, major improvements, in the field of image acquisition and analysis, are still required to be able to accurately characterize the liver parenchyma, monitor its changes and predict any pejorative evolution across disease progression. Artificial intelligence has the potential to augment the exploitation of massive multi-parametric data to extract valuable information and achieve precision medicine. Machine learning algorithms have been developed to assess non-invasively certain histological characteristics of chronic liver diseases, including fibrosis and steatosis. Although still at an early stage of development, artificial intelligence-based imaging biomarkers provide novel opportunities to predict the risk of progression from early-stage chronic liver diseases toward cirrhosis-related complications, with the ultimate perspective of precision medicine. This review provides an overview of emerging quantitative imaging techniques and the application of artificial intelligence for biomarker discovery in chronic liver disease., (© 2022. Asian Pacific Association for the Study of the Liver.)

Background: To investigate whether fractal analysis of perfusion differentiates hepatocellular adenoma (HCA) subtypes and hepatocellular carcinoma (HCC) in non-cirrhotic liver by quantifying perfusion chaos using four-dimensional dynamic contrast-enhanced magnetic resonance imaging (4D-DCE-MRI)., Results: A retrospective population of 63 patients (47 female) with histopathologically characterized HCA and HCC in non-cirrhotic livers was investigated. Our population consisted of 13 hepatocyte nuclear factor (HNF)-1α-inactivated (H-HCAs), 7 β-catenin-exon-3-mutated (b ex3 -HCAs), 27 inflammatory HCAs (I-HCAs), and 16 HCCs. Four-dimensional fractal analysis was applied to arterial, portal venous, and delayed phases of 4D-DCE-MRI and was performed in lesions as well as remote liver tissue. Diagnostic accuracy of fractal analysis was compared to qualitative MRI features alone and their combination using multi-class diagnostic accuracy testing including kappa-statistics and area under the receiver operating characteristic curve (AUC). Fractal analysis allowed quantification of perfusion chaos, which was significantly different between lesion subtypes (multi-class AUC = 0.90, p < 0.001), except between I-HCA and HCC. Qualitative MRI features alone did not allow reliable differentiation between HCA subtypes and HCC (κ = 0.35). However, combining qualitative MRI features and fractal analysis reliably predicted the histopathological diagnosis (κ = 0.89) and improved differentiation of high-risk lesions (i.e., HCCs, b ex3 -HCAs) and low-risk lesions (H-HCAs, I-HCAs) from sensitivity and specificity of 43% (95% confidence interval [CI] 23-66%) and 47% (CI 32-64%) for qualitative MRI features to 96% (CI 78-100%) and 68% (CI 51-81%), respectively, when adding fractal analysis., Conclusions: Combining qualitative MRI features with fractal analysis allows identification of HCA subtypes and HCCs in patients with non-cirrhotic livers and improves differentiation of lesions with high and low risk for malignant transformation., (© 2022. The Author(s).)

Background: The factors affecting intra-operator variability of two-dimensional shear wave elastography (2D-SWE) have not been clearly established. We evaluated 2D-SWE variability according to the number of measurements, clinical and laboratory features, and liver stiffness measurements (LSM)., Methods: At least three LSM were performed in 452 patients who underwent LSM by 2D-SWE (supersonic shear imaging) out of an initial database of 1650 patients. The mean value of the three LSM was our best measurement method. Bland-Altman plots were used to evaluate intra-operator variability when considering only one, or the first two measurements. Variability was assessed by taking the absolute value of the difference between the first LSM and the mean of the three LSM. Logistic regression was used to assess the factors associated with the highest tertile of variability., Results: The limit of agreement was narrower with the mean of the first and second measurements than with each measurement taken separately (- 2.83 to 2.99 kPa vs. - 5.86 to 6.21 kPa and - 5.77 to 5.73 kPa for the first and second measurement, respectively). A BMI ≥ 25 kg/m 2 and a first LSM by 2D-SWE ≥ 7.1 kPa increased the odds of higher variability by 3.4 and 3.9, respectively. Adding a second LSM didn't change the variability in patients with BMI < 25 and a first LSM by 2D-SWE < 7.1 kPa., Conclusions: Intra-operator variability of LSM by 2D-SWE increases with both a high BMI and high LSM value. In patients with BMI < 25 kg/m 2 and a first LSM < 7.1 kPa we recommend performing only one LSM., (© 2021. The Author(s).)

Objective: The aim of this study was to assess the prognostic value of liver surface nodularity (LSN) and sarcopenia from preoperative computed tomography (CT) in patients with resectable metabolic syndrome (MS)-related hepatocellular carcinoma (HCC)., Methods: Patients with MS undergoing hepatectomy for HCC between 2006 and 2018 at a single center were retrospectively analyzed. LSN and sarcopenia were assessed on preoperative CT scans, and their association with severe (Clavien-Dindo grade 3-5) postoperative complications was analyzed on multivariate analysis. The influence of LSN and sarcopenia on overall survival (OS) and recurrence-free survival (RFS) was assessed., Results: Overall, 110 patients (92 men [84%], mean 67.7 ± 7.7 years of age) were analyzed. Severe postoperative complications occurred in 34/110 (31%) patients. Patients with severe complications had a significantly higher LSN score (area under the receiver operating characteristic curve 0.68 ± 0.05, optimal cut-off > 2.50) and were more frequently sarcopenic (47% vs. 13% without major complications, p < 0.001). Multivariate analysis identified sarcopenia (odds ratio [OR] 6.51, 95% confidence interval [CI] 2.08-20.39; p < 0.001), LSN > 2.50 (OR 7.05, 95% CI 2.13-23.35; p < 0.001), and preoperative portal vein embolization (PVE; OR 6.06, 95% CI 1.71-21.48; p = 0.005) as independent predictors of severe complications. LSN and sarcopenia had no influence on OS. Stratification according to a combination of LSN > 2.50 and sarcopenia predicted the risk of severe postoperative complications from 7% (no sarcopenia and LSN ≤2.50) to 71% (sarcopenia and LSN > 2.50; p < 0.001), as well as RFS from 61 months (95% CI 40-82) to 17 months (95% CI 9-25; p = 0.033). Results remained significant in 52 patients without advanced fibrosis., Conclusions: The combination of LSN and sarcopenia derived from routine preoperative CT seems to help predict severe postoperative complications and stratification of RFS in patients with MS and resectable HCC.

Perfusion imaging allows for the quantitative extraction of physiological perfusion parameters of the liver microcirculation at levels far below the spatial the resolution of CT and MR imaging. Because of its peculiar structure and architecture, perfusion imaging is more challenging in the liver than in other organs. Indeed, the liver is a mobile organ and significantly deforms with respiratory motion. Moreover, it has a dual vascular supply and the sinusoidal capillaries are fenestrated in the normal liver. Using extracellular contrast agents, perfusion imaging has shown its ability to discriminate patients with various stages of liver fibrosis. The recent introduction of hepatobiliary contrast agents enables quantification of both the liver perfusion and the hepatocyte transport function using advanced perfusion models. The purpose of this review article is to describe the characteristics of liver perfusion imaging to assess chronic liver disease, with a special focus on CT and MR imaging.

Purpose: To establish measurement quality criteria for the noninvasive assessment of clinically significant portal hypertension (CSPH) in patients with cirrhosis using CT-based liver surface nodularity (LSN) measurements., Methods: Seventy-four consecutive patients with cirrhosis (mean 62 ± 13 years), including 30 with CSPH (41%), underwent CT and hepatic venous pressure gradient measurements. Three independent readers performed 15 LSN measurements/patient using dedicated software. LSN was computed based on the median and means of one to 15 measurements. Accuracy for diagnosing CSPH was assessed using receiver operating characteristic (ROC) curve analysis. Variability was assessed by the intra-class correlation coefficient (ICC) and the Bland-Altman plot (BA). Quality criteria were identified to maximize the accuracy of LSN and minimize variability., Results: The area under the (AU) ROCs of mean and median LSN measurements based on one to 15 measurements ranged from 0.79 ± 0.05 to 0.91 ± 0.04 and 0.86 ± 0.04 to 0.91 ± 0.03, respectively, with no difference on pair-wise comparisons (all p > 0.05). AUROCs of LSN increased from one to eight and leveled off between eight and 15 measurements. Inter- and intra-reader variability decreased from one to 15 measurements, with only slight improvement after more than eight measurements. Intra- and inter-observer agreements were excellent with eight measurements (ICC = 0.90 [95%CI 0.84-0.94], and ICC = 0.93 [95%CI 0.89-0.95], respectively), and variability for intra-observer and inter-observer agreement was low (BA bias 4.2% (95% limits of agreement [LoA] [- 15.3; + 23.7%]) and 4.8% LoA [ - 17.5; + 27.1%], respectively)., Conclusions: CT-based LSN measurement is highly reproducible and accurate. We suggest using at least 8 valid measurements to determine the mean LSN value for the detection of CSPH.

With the development of chemotherapy regimens, targeted therapies, and hepatic surgery, the survival of patients with colorectal liver metastases (CRLM) has dramatically improved. Imaging plays a central role for the diagnosis, staging, and treatment allocation in these patients. To interpret CRLM on imaging, radiologists must be familiar with the main imaging features of untreated tumors as well as the modifications induced by systemic therapies, and their meaning in relation to pathological tumor response and tumor biology. CRLM have the same histological features as the primary tumor. Most are "non-otherwise specified" (NOS) adenocarcinomas. The mucinous tumor is the most common of the rare subtypes. In NOS tumors, imaging usually differentiates central areas of necrosis from peripheral proliferating tumors and desmoplastic reaction. Areas of mucin mixed with fibrosis are seen in mucinous subtypes to help differentiate the metastases from other tumors cysts or hemangiomas. After treatment, the viable tumor is gradually replaced by ischemic-like necrosis and fibrosis, and remnants cells are mainly located on the periphery of tumors. Imaging can help predict the degree of tumor response, but changes can be difficult to differentiate from the pretherapeutic appearance. When chemotherapy is interrupted or in case of resistance to treatment, a peripheral infiltrating halo of tumor growth may appear. The purpose of the article is to illustrate the significance of the imaging features of colorectal liver metastases during systemic therapy, using radiopathological correlations.

The 2019 European Congress of Radiology program, "Women in Focus: Be Inspired," offered insights from successful women and men for overcoming a number of everyday work and personal life challenges. With regard to balancing career and personal life and achieving well-being, the advice of female and male radiology leaders on the front lines, throughout the world, shares common themes. This paper highlights and expands on points of advice and encouragement from the "Women in Focus" program. The first step is to know yourself, so you can set priorities. Then, take charge, be brave, and follow your dreams, which may not be the same as other people's. Finding balance requires examining your goals and acknowledging that you may not be able to get everything you want all at once. Receiving effective mentorship from numerous sources is key, as is finding an environment that supports your growth. It is important to surround yourself both at work and at home with people who support your ideas and give you a sense of peace, well-being, and resilience. If the culture does not fit, have the courage to move on. Current leaders should reach out to ensure the diversity of future teams. Society benefits, radiology benefits, and our patients benefit from a specialty that values equity, diversity, and inclusiveness.

Purpose: To assess and compare the performance of liver surface nodularity (LSN) quantification using Gd-BOPTA-enhanced MRI and contrast-enhanced CT for the diagnosis of clinically significant portal hypertension (CSPH) in patients with cirrhosis., Methods: This retrospective study included 30 patients with compensated histologically proven cirrhosis who underwent hepatic venous pressure gradient (HVPG), abdominal CT and Gd-BOPTA-MRI within a 60-day interval during pre-surgery workup for hepatocellular carcinoma (HCC) between January 2016 and August 2018. LSN score was derived from CT portal venous phase (PVP), axial T2- and T1-weighted PVP and hepatobiliary phase (HBP). Accuracy for the detection of CSPH was evaluated for each set of images by ROC curve analysis. Intra-observer, inter-observer and inter-method reproducibilities were assessed by the intraclass correlation coefficient (ICC) and coefficient of variation (CV)., Results: Thirty patients were analysed (23 men [77%], mean age 60 ± 11 years old), including 15 (50%) with CSPH. All CT- and MRI-derived LSN quantifications were correlated to HVPG (CT-PVP: r = 0.63, p = 0.001, AUROC = 0.908 ± 0.06; T1-w-PVP: r = 0.43, p = 0.028, AUROC = 0.876 ± 0.07; T1-w-HBP: r = 0.50, p = 0.012, AUROC = 0.823 ± 0.08; T2-w: r = 0.51, p = 0.007, AUROC = 0.801 ± 0.09). There was no significant difference in AUROC pairwise comparisons (p = 0.12-0.88). Patients with CSPH had higher LSN than those without (CT-PVP: 3.2 ± 0.6 vs 2.4 ± 0.5, p < 0.001; T1-w-PVP: 2.7 ± 0.4 vs 2.2 ± 0.4, p = 0.002; T1-w-HBP: 3.0 ± 0.6 vs 2.3 ± 0.3, p < 0.001; T2-w: 3.0 ± 0.6 vs 2.2 ± 0.3, p = 0.001) and 86%, 82%, 85% and 82% of patients were correctly classified, respectively. Reproducibility of inter-image set comparisons was excellent (ICC = 0.84-0.96 and CV = 8.3-14.2%)., Conclusion: The diagnostic performance of MRI-based LSN for detecting CSPH is strong and similar to that of CT-based LSN.

Objective: To investigate the presence of gender disparity in academic involvement during radiology residency and to identify and characterize any gender differences in perceived barriers for conducting research., Methods: An international call for participation in an online survey was promoted via social media and through multiple international and national radiological societies. A 35-question survey invited radiology trainees worldwide to answer questions regarding exposure and barriers to academic radiology during their training. Gender differences in response proportions were analyzed using either Fisher's exact or chi-squared tests., Results: Eight hundred fifty-eight participants (438 men, 420 women) from Europe (432), Asia (241), North and South America (144), Africa (37), and Oceania (4) completed the survey. Fewer women radiology residents were involved in research during residency (44.3%, 186/420 vs 59.4%, 260/438; p ≤ 0.0001) and had fewer published original articles (27.9%, 117/420 vs. 40.2%, 176/438; p = 0.001). Women were more likely to declare gender as a barrier to research (24.3%, 102/420 vs. 6.8%, 30/438; p < 0.0001) and lacked mentorship/support from faculty (65%, 273/420 vs. 55.7%, 244/438; p = 0.0055). Men were more likely to declare a lack of time (60.3%, 264/438 vs. 50.7%, 213/420; p = 0.0049) and lack of personal interest (21%, 92/438 vs. 13.6%, 57/420, p = 0.0041) in conducting research., Conclusion: Fewer women were involved in academic activities during radiology residency, resulting in fewer original published studies compared to their men counterparts. This is indicative of an inherent gender imbalance. Lack of mentorship reported by women radiologists was a main barrier to research.

Chemotherapy-induced hepatopathy includes a wide variety of parenchymal and vascular hepatic changes on imaging, including diffuse or focal hepatopathies (i.e. hepatitis, steatosis, fibrosis, pseudocirrhosis, or sinusoidal obstruction). These changes can profoundly alter the hepatic parenchyma on imaging and result in both false negative and false-positive diagnoses of hepatic metastases and lead to errors in patient management strategies. It is therefore important for radiologists to have a comprehensive knowledge of the imaging patterns that may develop following chemotherapy. The purpose of this review is to explore the broad spectrum of hepatic parenchymal and vascular chemotherapy-induced changes on CT and MR imaging.

Frequently encountered on abdominal imaging studies, the majority of common benign liver lesions are asymptomatic, confidently diagnosed by imaging, and do not require further workup, follow-up, or treatment. The increasing use of multimodality liver imaging, has allowed the recognition of uncommon evolutions of common benign liver lesions such as size changes, fibrotic regression, and content and vascularization changes, and their complications such as rupture, hemorrhage, thrombosis, extrinsic compression, and malignancy. The purpose of this pictorial review is to describe and illustrate the incidence and diagnostic features of these uncommon evolutions and complications on cross-sectional imaging, mainly on computed tomography and magnetic resonance imaging, with emphasis on those imaging clues which are helpful in the differential diagnosis or indicate the need for treatment.

A variety of vascular liver disorders can induce hepatocellular tumors. They may be related to portal venous deprivation, venous outflow obstruction, or arterial diseases. Their common feature is an imbalance between hepatic arterial and portal venous blood flow leading to an increased hepatic arterial inflow. Consequently, hepatocellular tumors may arise, most commonly focal nodular hyperplasia-like lesions but hepatocellular adenomas and hepatocellular carcinoma may be seen as well. This article will review the most common vascular liver diseases associated with hepatocellular nodules (Budd-Chiari syndrome, congenital portosystemic shunt, hereditary hemorrhagic telangiectasia, and portal cavernoma). For each condition, imaging findings will be described as well as the differential diagnosis and the diagnostic clues.

Budd-Chiari syndrome (BCS) is defined by clinical and laboratory signs associated with partial or complete impairment of hepatic venous drainage in the absence of right heart failure or constrictive pericarditis. Primary BCS is the most frequent type and is a complication of hypercoagulable states, in particular myeloproliferative neoplasms. Secondary BCS involves tumor invasion or extrinsic compression. Most patients present with chronic BCS including a non-cirrhotic, dysmorphic, chronic liver disease with various degrees of fibrosis deposition. Acute BCS is rare, and patients present with hepatomegaly, ascites, and hepatic insufficiency. The diagnosis is based on imaging. Imaging features include (1) direct signs, in particular occlusion or compression of the hepatic veins and/or the inferior vena cava and venous collaterals and (2) indirect signs, in particular morphological changes in the liver with hypertrophy of the caudate lobe and delayed nodule formation. Ultrasound and magnetic resonance imaging are the gold standard for diagnosis. The aim of this review is to provide an overview of the role of imaging in the diagnosis of BCS.

The management of patients with well-differentiated neuroendocrine tumors (NET) and non-resectable liver metastases is challenging. Liver-directed transarterial embolization (TAE), transarterial chemo-embolization (TACE) and selective internal radiation therapy (SIRT) have a place of choice among other treatment modalities. However, their utilization relies on a low level of proof, due to the lack of prospective data, the absence of comparative studies and considerable heterogeneity between local practices. TAE and TACE generally achieve average symptomatic, biological and radiological responses of 75%, 56% and 50%, with progression-free survival of 12-18 months, with acceptable tolerance. Although not clearly demonstrated, TACE may be more effective than TAE in pancreatic NET, but not in small-intestine NET. SIRT has been developed more recently and may achieve similar results, with improved tolerance, but decreased cost-effectiveness, although no prospective comparison has been published to date. There is currently no strong argument to choose between TAE, TACE and SIRT, and they have not been compared to other treatment modalities. The evaluation of their efficacy has mostly relied on criteria based on size variations, which do not take into account tumor viability and metabolism, and thus may not be relevant. These techniques may be especially effective when performed as first-line therapies, in patients with non-major liver involvement (<75%) and with hypervascular metastases. Finally, studies exploring their combination with systemic therapies are ongoing.

Purpose: To evaluate the qualitative and quantitative benefit of multiple arterial phase acquisitions for the depiction of hypervascularity in FNH explored MR imaging using an extracellular contrast agent., Methods: Between 2007 and 2014, all patients who underwent MR imaging for the exploration of FNH were included. The protocol included a single or a triple arterial phase ("single" and "triple" group, respectively). Arterial phases were visually divided into four types: (1) angiographic, (2) early, (3) late, and (4) portal. Signal intensity on arterial phase images was visually recorded as intense, moderate, or low for each lesion. Lesion-to-liver contrast (LLC) and relative lesion enhancement (RE) were calculated and compared between the two groups using the Mann-Whitney test., Results: Thirty-five women were included (mean 45-year old, range 20-66), with 50 FNH (mean size 30 mm). Single and triple groups included 20 patients (30 FNH) and 15 patients (20 FNH), respectively. Signal intensity was intense in all lesions in the triple group and in 22/30 (73%) in the single group (p = 0.041). Intense signals were more frequently found in the early arterial phase (p < 0.001). RE was not significantly different (1.78 ± 0.84 vs. 1.98 ± 1.81 p = 0.430, in the single and triple groups, respectively) but LLC was significantly higher in the triple group (0.32 ± 0.10 vs. 0.22 ± 0.10, p = 0.005). LLC was significantly higher in the first two arterial phases in the triple group (p < 0.001)., Conclusion: Acquisition of three arterial phases improves the visualization of hypervascularity of FNH, as lesions show high visual signal intensity and contrast. Optimal visualization is obtained in the early arterial phase.

Purpose: To compare tumor progression in both embolized and non-embolized liver lobes after portal vein embolization (PVE) in patients with bilobar colorectal liver metastases (CLM), according to the initial response to induction chemotherapy., Methods: From 2002 to 2012, a total of 42 consecutive patients with bilobar CLM initially treated using induction chemotherapy underwent right PVE to achieve adequate future liver remnant volume. Tumoral and liver parenchyma volumes, as well as their volume variations, were measured on computed tomography before and after PVE in both embolized and non-embolized. Patients were classified as fast (≤6 cycles of induction chemotherapy) and slow (>6 cycles) responders., Results: Overall, 432 metastases were analyzed in 42 patients. Patients were slow responders in 29 (69 %) cases. Tumoral volume increased in 29 (69 %) cases in the embolized liver (+48 %; p < 0.0001), and in 28 (66 %) cases in the non-embolized liver (+31 %; p < 0.0001). Fast responders had a tumoral volume decrease in both embolized (-4 %) and non-embolized (-9 %) lobes. On the opposite side, slow responders had tumoral volume increase in both embolized (+79 %) and non-embolized (+32 %) lobes. On multivariate analysis, a 'slow' response to induction chemotherapy was the only factor associated with tumoral progression in both embolized (p = 0.0012) and non-embolized (p = 0.001) lobes., Conclusion: Tumor growth after PVE is observed in both embolized and non-embolized liver lobes in most patients but is significantly associated with slow response to induction chemotherapy.

Unlabelled: As an integral part of the European Commission (EC) Imaging Referral Guidelines Project a 1.5-day workshop was held in Vienna on 20-21 September, 2012. At this workshop, models and good practices regarding the appropriateness and use of imaging referral guidelines (Guidelines) in Europe and worldwide were presented, together with the results of a survey of Guidelines in Europe. The latter included ideas, innovations and wishes for future Community action., Main Messages: Recommendations for future Community action: Stronger measures should be taken by the EC and the European competent authorities for making Guidelines available and used in all EU member states. Evidence-based Guidelines with separate guidance for children should be issued or endorsed by a trusted European organisation. Educational initiatives and electronic requesting in connection with clinical decision support (CDS) systems should be used to improve the implementation of Guidelines. Monitoring of Guidelines implementation and use should be by clinical audit, particularly external audit, but also by local/internal audit.

Unlabelled: The objective of this study was to devise and implement a Europe-wide study on referral guidelines for radiological imaging in the EU Member States in order to identify potential major issues, important differences between Member States and good practices. A web-based survey was used to assess the availability of imaging referral guidelines, development methodology and preferences for future initiatives for European community action to facilitate justification and appropriate use of radiological diagnostic procedures. A questionnaire was distributed to representatives of national radiological and nuclear medicine societies as well as to competent authorities for radiation protection in 30 European countries, including all 28 EU Member States. Responses were collated and analysed to produce a series of conclusions and recommendations., Main Messages: • Survey respondents in 21/30 countries were aware of legal requirements for Guidelines • Survey respondents in 18/30 countries were aware of the availability of Guidelines in their country. • The majority of responders support the development of European Guidelines. These may either be from a combination of multiple national Guidelines with consensus or Pan-European Guidelines developed centrally. • Guidelines developed in two countries included all of the following important features: radiation dose information; specific advice for imaging children; specific advice for the pregnant woman/unborn child; an evidence-based process; a formal consensus for recommendations. • Suggestions for additional measures needed to reinforce the use of Guidelines include: educational initiatives; integrating Guidelines into clinical decision support systems; clinical audit for monitoring of the availability, use and implementation of Guidelines.

Background: In patients operated on for colorectal liver metastasis (CRLM), metastatic lymph node (LN) of the hepatic pedicle is a major prognostic factor. Efficiency of preoperative computed tomography (CT) and intraoperative examination for the diagnosis of metastatic LN of hepatic pedicle is prospectively evaluated., Methods: From January 2008 to June 2010, 76 patients underwent liver resection for CRLM, with systematic LN pedicle dissection. Preoperative CT scan evaluated prospectively location, size, and aspect of LN, whereas the surgeon assessed size and consistency of LN Results of CT and intraoperative findings were compared with pathologic findings to determine sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV)., Results: A total of 241 nodes were analyzed (3.2 ± 2.1 LN per patient). Systematic LN dissection increased the operative time by a mean of 20 ± 12.5 min, without any specific morbidity or mortality related to the LN clearance. Metastatic LN in the hepatic pedicle was observed in 15 (20%) patients and were unrelated to the number, size, and location of CRLM. NPV and PPV of the preoperative CT scan was 85 and 56%, respectively. Intraoperative evaluation of LN had a high NPV of 91% with a low PPV of 43%. Even with the combination of CT and intraoperative evaluation, 27% of the patients with a pathological metastatic LN were not suspected., Conclusions: Because neither the preoperative CT nor the surgical evaluation accurately predicts metastatic LN in the hepatic pedicle, accurate oncological staging require a systematic pedicular LN clearance during liver resection for CRLM.

Background: This prospective study evaluated the effect of bevacizumab on the hypertrophy of the future liver remnant (FLR) after portal vein occlusion (PVO) before major hepatectomy for colorectal liver metastases., Methods: Twenty-seven patients with colorectal liver metastases treated with preoperative FOLFOX/FOLFIRI chemotherapy regimen since 2002 were evaluated for the degree of hypertrophy of the FLR after right PVO. The results were compared with a similar group of 13 patients treated since 2006 with a chemotherapeutic regimen including bevacizumab and PVO. The FLR was measured by volumetric computed tomography 4 weeks before and after PVO., Results: Before PVO, the FLR volumes were similar in the 13 patients who received bevacizumab (bev+) (mean +/- standard deviation, 497 +/- 136 cm(3)) and the 27 patients who did not receive bevacizumab (bev-) (511 +/- 222 cm(3), P = NS). After PVO, the increase in the FLR volume was significantly lower in the bev+ group (561 +/- 171 cm(3)) compared with the bev- group (667 +/- 213 cm(3), P < .031). In the bev+ group, patients who had received six or more cycles and were > or =60 years old experienced far lower hypertrophy. A right hepatectomy was performed in 29 patients (72%) without mortality and no clinically important differences in morbidity., Conclusions: Bevacizumab may impair hypertrophy of the FLR after PVO in preparation for major hepatectomy particularly, in patients aged > or =60 years and those who receive six or more cycles of bevacizumab, suggesting that major liver resection should be considered with caution in patients who have received bevacizumab.

Background: Aim of this retrospective study was to compare induction of left liver hypertrophy after right portal vein ligation (PVL) and right portal vein embolization (PVE) before right hepatectomy for liver metastases., Materials and Methods: Between 1998 and 2005, 18 patients underwent a PVE, whereas 17 patients underwent a PVL during a first stage laparotomy., Results: There was no complication related to PVE or PVL. After a similar interval time (7 +/- 3 vs 8 +/- 3 weeks), the increase of the left liver volume was similar between the two groups (35 +/- 38 vs 38 +/- 26%). After PVE and PVL, right hepatectomy was performed in 12 and 14 patients, respectively. Technical difficulties during the right hepatectomy were similar according to duration of procedure (6.4 +/- 1 vs 6.7 +/- 1 h, p = 0.7) and transfusion rates (33 vs 28%, p = 0.7). Mortality was nil in both groups, and morbidity rates were respectively 58% for the PVE group and 36% for the PVL group (p = 0.6)., Conclusion: Right PVL and PVE result in a comparable hypertrophy of the left liver. During the first laparotomy of a two-step liver resection, PVL can be efficiently and safely performed.

Background: The aim of this study was to evaluate the utility of staging laparoscopy in patients with biliary cancers in the era of modern diagnostic imaging., Methods: From September 2002 through August 2004, 39 consecutive patients with potentially resectable cholangiocarcinoma underwent preoperative staging laparoscopy before laparotomy. Preoperative imaging included ultrasonography and triphasic computed tomography for all patients and magnetic resonance cholangiography in 35 patients (90%). Final pathological diagnosis included 20 hilar cholangiocarcinomas (HC), 11 intrahepatic cholangiocarcinomas (IHC), and eight gallbladder carcinomas (GBC)., Results: During laparoscopy, unresectable disease was found in 14/39 patients (36%). The main causes of unresectability were peritoneal carcinomatosis (11/14) and liver metastases (5/14). At laparotomy, nine patients (37%) were found to have advanced disease precluding resection. Vascular invasion and nodal metastases were the main causes of unresectability during laparotomy (eight out of nine). In detecting peritoneal metastases and liver metastases, laparoscopy had an accuracy of 92 and 71%, respectively. All patients with vascular or nodal involvement were missed by laparoscopy. For prediction of unresectability disease, the yield and accuracy of laparoscopy were highest for GBC (62% yield and 83% accuracy), followed by IHC (36% yield and 67% accuracy) and HC (25% yield and 45% accuracy), Conclusion: Staging laparoscopy ensured that unnecessary laparotomy was not performed in 36% of patients with potentially resectable biliary carcinoma after extensive preoperative imaging. In patients with biliary carcinoma that appears resectable, staging laparoscopy allows detection of peritoneal and liver metastasis in one third of patients. Both vascular and lymph nodes invasions were not diagnosed by this procedure. Due to these limitations, laparoscopy is more useful in ruling out dissemination in GBC and IHC than in HC.

In patients with multiple colorectal liver metastases, the technical limits of curative surgery can be overcome by both reducing tumor volume with preoperative chemotherapy and by increasing the future remnant liver with portal vein embolization. Chemotherapy is generally discontinued before the embolization because it is alleged to impair hypertrophy of the future remnant liver. We have tested this assumption by comparing two groups of patients who had undergone right portal vein obstruction: 10 patients in whom chemotherapy was maintained until surgery and 10 patients in whom it was interrupted at least 1 month prior to portal obstruction. The two groups, with and without chemotherapy, were comparable for patient's age (60 +/- 9 versus 61 +/- 9 years), number of metastases (7.7 +/- 3 versus 6.2 +/- 3), and future remnant liver volume (25 +/- 9% versus 23 +/- 5% of the total liver). After right portal vein obstruction, the increase of the future remnant liver was comparable in the two groups (33 +/- 26% versus 25 +/- 7%). Liver resection was performed in 14 patients (7 in each group) with a similar morbidity rate (57% in each group). In conclusion, continuing chemotherapy while portal vein obstruction is performed did not impair the hypertrophy of the future remnant volume nor the postoperative course after liver resection. Therefore, chemotherapy can be safely continued until liver surgery, when portal vein obstruction is indicated.