Benign and malignant hepatocellular lesions in patients with vascular liver diseases

Diagnostic approach to hepatic vascular lesions: a paediatric perspective

The pathological evaluation of hepatic vascular lesions in children requires special consideration. Inconsistent terminology, rarity of pathology specimens and overlapping pathological features between various lesions may pose a serious diagnostic challenge. In this review, we highlight the importance of using the International Society for the Study of Vascular Anomalies (ISSVA) classification scheme to characterise these lesions. Selected entities are discussed, including hepatic vascular tumours exclusively seen in the paediatric age group, hepatic infantile haemangioma and hepatic congenital haemangioma. Vascular malformations, with emphasis on their syndromic associations (venous malformation in blue rubber bleb naevus syndrome) and complications (hepatocellular nodules in Abernethy malformation) are also covered.

[Splanchnic vein thrombosis]

Splanchnic vein thrombosis includes Budd-Chiari syndrome and portal vein thrombosis. These diseases share common features: (i) they are rare diseases and (ii) they can lead to portal hypertension and its complications. Budd-Chiari syndrome and portal vein thrombosis in the absence of underlying liver disease share many risk factors, the most common being myeloproliferative neoplasms. A rapid and comprehensive workup for thrombosis risk factors is necessary in these patients. Long-term anticoagulation is indicated in most patients. Portal vein thrombosis can also develop in patients with cirrhosis, and is associated with a worse course of cirrhosis. Indications for anticoagulation in patients with cirrhosis are increasing. Transjugular intrahepatic portosystemic shunt is a second-line procedure in this setting. Because of the rarity of these diseases, high-level evidence studies are rare. However, collaborative studies have provided a better understanding of their natural history and allowed to improve the management of these patients. This review focuses on the causes, diagnosis, and management of patients with Budd-Chiari syndrome, patients with portal vein thrombosis without underlying liver disease, and patients with cirrhosis and portal vein thrombosis.

Expert management of congenital portosystemic shunts and their complications

Congenital portosystemic shunts are often associated with systemic complications, the most challenging of which are liver nodules, pulmonary hypertension, endocrine abnormalities, and neurocognitive dysfunction. In the present paper, we offer expert clinical guidance on the management of liver nodules, pulmonary hypertension, and endocrine abnormalities, and we make recommendations regarding shunt closure and follow-up.

Focal nodular hyperplasia-like nodules arising in the setting of hepatic vascular disorders with portosystemic shunting show β-catenin activation

Hepatocellular nodules can develop in the setting of chronic hepatic vascular disorders including those characterized by portosystemic shunts such as Abernethy malformation and post-Fontan procedure. The nodules can range from benign lesions such as regenerative nodules, focal nodular hyperplasia (FNH), and hepatocellular adenoma (HCA) to malignant neoplasms such as hepatocellular carcinoma (HCC). In many instances, these nodules are difficult to place into well-defined categories based on radiologic or histologic features. Nodular lesions that resemble FNH are common in this context and have been described as FNH-like nodules, the nature of which is not well-established. This study examines 6 liver resections from patients with vascular disease characterized by portosystemic shunts. A wide range of nodules were present in these cases, including regenerative nodules (n = 2), FNH and FNH-like (n = 30), HCA (n = 10), HCA-like (n = 13), and HCC (n = 2). Six nodules from 3 patients were categorized as FNH-like due to one or more features such as nodular architecture, fibrous septa, and ductular reaction, but lack of typical map-like glutamine synthetase (GS) staining. Further characterization of these 6 FNH-like nodules showed diffuse GS staining in all nodules (3 diffuse homogeneous, 3 diffuse heterogeneous). Targeted next-generation sequencing identified CTNNB1 alterations in all tested FNH-like nodules (n = 4). These results indicate that FNH-like nodules in the setting of chronic hepatic vascular disorders can be neoplastic. Since the presence of β-catenin activation portends a potential risk for malignant progression, GS and β-catenin immunohistochemistry should be obtained in all cases showing FNH-like morphology, with molecular analysis performed in cases with indeterminate staining pattern.

Congenital extrahepatic Portosystemic shunt with hypoplasia of the intrahepatic inferior vena cava: A rare case report

Congenital portosystemic shunt (CPS) is a rare vascular anomaly resulting in diversion of splanchnic or portal blood into the systemic circulation. Other vascular malformations associated with this entity are uncommon. A 4-year-old female child with a diagnosis of acute viral hepatitis had an incidental finding of extrahepatic CPS on a Doppler abdominal ultrasound. Contrast-enhanced computed tomography showed a dilated portal vein having H-type side-to-side communication with a hypoplastic intrahepatic portion of the inferior vena cava and a prominent dilated azygos vein. There was retroaortic left renal vein drained into the IVC which was visualized in its entirety. Echocardiography findings were normal and the patient was discharged after symptomatic treatment that achieved improvement. With the expansion of abdominal imaging, incidental cases of CPS are increasingly being diagnosed in children. Although vascular malformations associated with CPS are rare, early diagnosis of cases helps avoid complications during shunt closure.

Focal Liver Lesions in Budd-Chiari Syndrome: Spectrum of Imaging Findings

Budd-Chiari syndrome (BCS) is a rare clinical entity characterized by hepatic venous outflow obstruction, resulting in liver congestion and subsequent chronic parenchymal damage. This condition often leads to the development of focal liver lesions, including benign focal nodular hyperplasia-like regenerative nodules, hepatocellular carcinoma, and perfusion-related pseudo-lesions. Computed tomography, ultrasound, and magnetic resonance are the commonly employed imaging modalities for the follow-up of BCS patients and for the detection and characterization of new-onset lesions. The accurate differentiation between benign and malignant nodules is crucial for optimal patient management and treatment planning. However, it can be challenging due to the variable and overlapping characteristics observed. This review aims to provide a comprehensive overview of the imaging features and differential diagnosis of focal liver lesions in BCS, emphasizing the key findings and discussing the challenges associated with their interpretation, with the purpose of facilitating the subsequent clinical decision-making.

Management of splanchnic vein thrombosis

The expression splanchnic vein thrombosis encompasses Budd-Chiari syndrome and portal vein thrombosis. These disorders have common characteristics: they are both rare diseases which can cause portal hypertension and its complications. Budd-Chiari syndrome and portal vein thrombosis in the absence of underlying liver disease share many risk factors, among which myeloproliferative neoplasms represent the most common; a rapid comprehensive work-up for risk factors of thrombosis is needed in these patients. Long-term anticoagulation is indicated in most patients. Portal vein thrombosis can also develop in patients with cirrhosis and in those with porto-sinusoidal vascular liver disease. The presence and nature of underlying liver disease impacts the management of portal vein thrombosis. Indications for anticoagulation in patients with cirrhosis are growing, while transjugular intrahepatic portosystemic shunt is now a second-line option. Due to the rarity of these diseases, studies yielding high-grade evidence are scarce. However, collaborative studies have provided new insight into the management of these patients. This article focuses on the causes, diagnosis, and management of patients with Budd-Chiari syndrome, portal vein thrombosis without underlying liver disease, or cirrhosis with non-malignant portal vein thrombosis.

Imaging features facilitate diagnosis of porto-sinusoidal vascular disorder

OBJECTIVES

Porto-sinusoidal vascular disorder (PSVD) is a recently defined vascular liver disease. Since diagnosis remains challenging, we aimed to evaluate radiological features that are distinct between PSVD and cirrhosis.

METHODS

Clinical, laboratory, and radiological parameters (CT/MRI) of patients with histologically-confirmed PSVD vs. cirrhosis vs. non-cirrhotic parenchymal liver disease were retrospectively evaluated.

RESULTS

Sixty-three PSVD, 155 cirrhosis, and 41 non-cirrhotic patients were included. As compared to cirrhosis, PSVD patients were younger and had lower HVPG, liver stiffness, and MELD. Routine clinical and imaging findings indicative of portal hypertension were similarly common. Intrahepatic portal tract abnormalities (49% vs. 15%; p < 0.001), FNH-like lesions (30% vs. 1%; p < 0.001), and abnormal liver morphology defined as peripheral parenchymal atrophy and compensatory hypertrophy of central segments (32% vs. 7%; p < 0.001) were significantly more common in PSVD patients. Hypertrophy of segment I (70% vs. 84%; p = 0.019), atrophy of segment IV (24% vs. 47%; p = 0.001), and nodular liver surface (22% vs. 89%; p < 0.001) were more common in patients with cirrhosis. In patients with gadoxetic acid-enhanced MRI, we identified the distinct imaging feature of "periportal hyperintensity" in the hepatobiliary phase (HBP) in 42% of patients with PSVD (14/33) vs. 1% in cirrhosis (1/95) vs. 0% in non-cirrhotic controls (0/41); p < 0.001).

CONCLUSIONS

Diagnosis of PSVD must be considered in younger patients presenting with clinical features of portal hypertension, portal tract abnormalities, and FNH-like lesions on CT/MRI. 'Periportal hyperintensity' in the HBP of gadoxetic acid-enhanced MRI was identified as a specific radiological feature of PSVD.

KEY POINTS

• Cross-sectional imaging can provide essential information to identify patients with porto-sinusoidal vascular disorder (PSVD). • Intrahepatic portal tract abnormalities, FNH-like lesions, and abnormal liver morphology are common in PSVD patients. • Periportal hyperintensity on the hepatobiliary phase of gadoxetic acid-enhanced MRI seems to be specific for patients with PSVD.

Budd-Chiari syndrome and its associated hepatocellular carcinoma: Clinical risk factors and potential immunotherapeutic benefit analysis

Background

Hepatocellular carcinoma (HCC) is a well-described complication of Budd-Chiari syndrome (BCS). However, the risk factors of BCS in developing HCC and clinical characteristics and imaging features of BCS-associated HCC is still to be determined.

Methods

Data from 113 consecutive patients with primary BCS in Qilu hospital were retrospectively studied. The clinical features of 12 HCC patients associated with BCS were also analyzed. Chi-square analysis was performed to analyze the differences in clinical characteristics. The treatment regime and CT imaging features of BCS-associated HCC were also illustrated.

Results

113 consecutive patients admitted to our hospital between January 2009 and June 2016 with a primary diagnosis of BCS were enrolled. 10.6% (12/113) was diagnosed with HCC. The BCS patients were mainly male gender with an average age of 49.2 years. Symptom duration longer than one year exhibited decreased serum ALT and AST and increased ascites ratio. BCS-associated HCC patients were presented with IVC block and stricture of the hepatic venous outflow tract. Patients with HCC were older and showed elevated serum AST and total bilirubin. Most nodules of HCC located in the right posterior lobe with heterogeneous enhancement during the arterial phase and washout during the delayed phase.

Conclusions

The results indicate that BCS patients with IVC block and stricture of hepatic venous outflow tract seem to be associated with HCC. BCS associated HCC nodules exhibited irregular and heterogeneous enhancement in the arterial phase and washout on the delayed phase.

Benign liver tumours: understanding molecular physiology to adapt clinical management

Improvements in understanding the pathophysiology of the different benign liver nodules have refined their nosological classification. New criteria have been identified using imaging, histology and molecular analyses for a precise diagnosis of these tumours. Improvement in the classification of liver tumours provides a more accurate prediction of disease progression and has modified patient management. Haemangioma and focal nodular hyperplasia, the most common benign liver tumours that develop in the absence of chronic liver disease, are usually easy to diagnose on imaging and do not require specific treatment. However, hepatocellular adenomas and cirrhotic macronodules can be difficult to discriminate from hepatocellular carcinoma. The molecular subtyping of hepatocellular adenomas in five major subgroups defined by HNF1A inactivation, β-catenin mutation in exon 3 or exon 7/8, and activation of inflammatory or Hedgehog pathways helps to identify the tumours at risk of malignant transformation or bleeding. New clinical, biological and molecular tools have gradually been included in diagnostic and treatment algorithms to classify benign liver tumours and improve patient management. This Review aims to explain the main pathogenic mechanisms of benign liver tumours and how this knowledge could influence clinical practice.

Hepatocellular Adenoma: What We Know, What We Do Not Know, and Why It Matters

In the last 2 decades there has been significant progress in research and diagnosis of hepatocellular adenoma (HCA), resulting in the establishment of a molecular and immunohistological HCA classification. This review aims to fine-tune the current expertise in order to enhance the histopathological diagnostic possibilities, by refining issues that are already known, addressing diagnostic difficulties and identifying still unknown aspects of HCA. We will discuss novel methods to identify HCA subtypes, in particular the sonic hedgehog HCAs and the interpretation of glutamine synthetase patterns for the recognition of beta-catenin mutated HCAs. The major complications of HCAs, bleeding and malignant transformation, will be considered, including the dilemmas of atypical and borderline lesions. Paragraphs on HCAs in different clinical and geographical settings, e.g. pregnancy, cirrhosis and non-western countries are included. The natural history of the different HCA subtypes in relation with age, sex and risk factors is a feature still insufficiently investigated. This is also true for the risks of clinical bleeding and malignant transformation in association with HCA subtypes. As HCA is a relatively rare tumor, a multicenter and multidisciplinary approach across geographical boundaries will be the appropriate method to establish prospective programs to identify, classify and manage HCAs, focusing on several aspects, e.g. etiology, underlying liver disease, complications, regression and growth. Updating what we know, identifying and addressing features that we do not know matters to warrant optimal patient management.

MR imaging features and long-term evolution of benign focal liver lesions in Budd-Chiari syndrome and Fontan-associated liver disease

PURPOSE

To compare the magnetic resonance imaging (MRI) features of benign liver lesions developed on Budd-Chiari syndrome (BCS) with those on Fontan-associated liver disease (FALD) and to describe their long-term progression.

MATERIALS AND METHODS

Patients with BCS or FALD who underwent MRI between 2010 and 2020 were retrospectively included. MRI features of nodules (≥ 5 mm) at baseline and at final follow-up were reviewed. The final diagnosis of benign lesion was based on a combination of clinical and biological data and findings at follow-up MRI examination.

RESULTS

Two-hundred and thirty benign liver lesions in 39 patients with BCS (10 men, 29 women; mean age, 36 ± 11 [SD] years; age range: 15-66 years) and 84 benign lesions in 14 patients with FALD (2 men, 12 women; mean age, 31 ± 10 [SD] years; age range: 20-48 years) were evaluated. On baseline MRI, BCS nodules were more frequently hyperintense on T1-weighted (183/230, 80%) and hypointense on T2-weighted (142/230; 62%) images, while FALD nodules were usually isointense on both T1- (70/84; 83%) and T2-weighted (64/84; 76%) images (all P< 0.01). Most lesions showed arterial phase hyperenhancement (222/230 [97%] vs. 80/84 [95%] in BCS and FALD, respectively; P = 0.28) but wash-out was more common in BCS (64/230 [28%] vs. 9/84 [11%]; P < 0.01). At follow-up, changes were more frequent in BCS nodules with more frequent disappearance (P < 0.01), changes in size, signal intensity on T2-weighted, portal, and delayed phase, and in the depiction of washout and capsule (all P ≤ 0.03).

CONCLUSION

MRI features of benign lesions are different at diagnosis and during the course of the disease between BCS and FALD. Changes in size and MRI features are more frequent in benign lesions developed in BCS.

An Adult Case of Congenital Extrahepatic Portosystemic Shunt Successfully Treated with Balloon-occluded Retrograde Transvenous Obliteration

A 42-year-old woman visited our hospital due to syncope. Contrast-enhanced CT revealed portosystemic shunt, portal vein hypoplasia, and multiple liver nodules. The histological examination of a liver biopsy specimen exhibited portal vein hypoplasia and revealed that the liver tumor was positive for glutamine synthetase. The patient was therefore diagnosed with congenital extrahepatic portosystemic shunt type II, and with focal nodular hyperplasia (FNH)-like nodules. She had the complication of severe portopulmonary hypertension and underwent complete shunt closure by balloon-occluded retrograde transvenous obliteration (B-RTO). The intrahepatic portal vein was well developed at 1 year after B-RTO, and multiple liver nodules completely regressed. Her pulmonary hypertension also improved.

Budd-Chiari syndrome: consensus guidance of the Asian Pacific Association for the study of the liver (APASL)

Budd Chiari syndrome (BCS) is a diverse disease with regard to the site of obstruction, the predisposing thrombophilic disorders and clinical presentation across the Asia-Pacific region. The hepatic vein ostial stenosis and short segment thrombosis are common in some parts of Asia-Pacific region, while membranous obstruction of the vena cava is common in some and complete thrombosis of hepatic veins in others. Prevalence of myeloproliferative neoplasms and other thrombophilic disorders in BCS varies from region to region and with different sites of obstruction. This heterogeneity also raises several issues and dilemmas in evaluation and approach to management of a patient with BCS. The opportunity to recanalize hepatic vein in patients with hepatic vein ostial stenosis or inferior vena cava stenting or pasty among those membranous obstruction of the vena cava is a unique opportunity in the Asia-Pacific region to restore hepatic outflow closely mimicking physiology. In order to address these issues arising out of the diversity as well as the unique features in the region, the Asia Pacific Association for Study of Liver has formulated these guidelines for clinicians.

Angiogenesis in the progression from liver fibrosis to cirrhosis and hepatocelluar carcinoma

Introduction: Persistent inflammation and hypoxia are strong stimulus for pathological angiogenesis and vascular remodeling, and are also the most important elements resulting in liver fibrosis. Sustained inflammatory process stimulates fibrosis to the end-point of cirrhosis and sinusoidal portal hypertension is an important feature of cirrhosis. Neovascularization plays a pivotal role in collateral circulation formation of portal vein, mesenteric congestion, and high perfusion. Imbalance of hepatic artery and portal vein blood flow leads to the increase of hepatic artery inflow, which is beneficial to the formation of nodules. Angiogenesis contributes to progression from liver fibrosis to cirrhosis and hepatocellular carcinoma (HCC) and anti-angiogenesis therapy can improve liver fibrosis, reduce portal pressure, and prolong overall survival of patients with HCC. Areas covers: This paper will try to address the difference of the morphological characteristics and mechanisms of neovascularization in the process from liver fibrosis to cirrhosis and HCC and further compare the different efficacy of anti-angiogenesis therapy in these three stages. Expert opinion: More in-depth understanding of the role of angiogenesis factors and the relationship between angiogenesis and other aspects of the pathogenesis and transformation may be the key to enabling future progress in the treatment of patients with liver fibrosis, cirrhosis, and HCC.

Fontan-associated liver disease

OBJECTIVE

To review the pathophysiology of Fontan-associated liver disease, its histologic changes, and its radiologic manifestations.

CONCLUSIONS

Fontan-associated liver disease is the result of a set of structural and functional changes in the liver that occur secondary to hemodynamic changes brought about by Fontan surgery. The radiologic manifestations of Fontan-associated liver disease consist of changes in the size and shape of the liver, alterations in the signal intensity or pattern of enhancement, abnormalities in the vascular structures, and focal lesions, which include benign nodules with intense uptake in the arterial phase and hepatocellular carcinoma. Radiologists need to be familiar with this disease and its complications, because the number of patients who undergo Fontan surgery continues to increase, and these patients undergo an increasing number of imaging tests.

Spectrum of liver lesions hyperintense on hepatobiliary phase: an approach by clinical setting

Hepatobiliary MRI contrast agents are increasingly being used for liver imaging. In clinical practice, most focal liver lesions do not uptake hepatobiliary contrast agents. Less commonly, hepatic lesions may show variable signal characteristics on hepatobiliary phase. This pictorial essay reviews a broad spectrum of benign and malignant focal hepatic observations that may show hyperintensity on hepatobiliary phase in various clinical settings. In non-cirrhotic patients, focal hepatic observations that show hyperintensity in the hepatobiliary phase are usually benign and typically include focal nodular hyperplasia. In patients with primary or secondary vascular disorders, focal nodular hyperplasia-like lesions arise as a local hyperplastic response to vascular alterations and tend to be iso- or hyperintense in the hepatobiliary phase. In oncologic patients, metastases and cholangiocarcinoma are hypointense lesions in the hepatobiliary phase; however, occasionally they may show a diffuse, central and inhomogeneous hepatobiliary paradoxical uptake with peripheral rim hypointensity. Post-chemotherapy focal nodular hyperplasia-like lesions may be tricky, and their typical hyperintense rim in the hepatobiliary phase is very helpful for the differential diagnosis with metastases. In cirrhotic patients, hepatocellular carcinoma may occasionally appear hyperintense on hepatobiliary phase.

Transjugular intrahepatic portosystemic shunt for Budd-Chiari syndrome: A comprehensive review

Budd-Chiari syndrome (BCS) is a relatively rare clinical condition with a wide range of symptomatology, caused by the obstruction of the hepatic venous outflow. If left untreated, it has got an high mortality rate. Its management is based on a step-wise approach, depending on the clinical presentation, and includes different treatment from anticoagulation therapy up to Interventional Radiology techniques, such as transjugular intrahepatic portosystemic shunt (TIPS). TIPS is today considered a safe and highly effective treatment and should be recommended for BCS patients, including those awaiting orthotopic liver transplantation. In this review the pathophysiology, diagnosis and treatment options of BCS are presented, with a special focus on published data regarding the techniques and outcomes of TIPS for the treatment of BCS. Moreover, unresolved issues and future research will be discussed.

Restenosis after recanalization for Budd-Chiari syndrome: Management and long-term results of 60 patients

BACKGROUND

Budd-Chiari syndrome is defined as hepatic venous outflow tract obstruction. For Asian Budd-Chiari syndrome patients, the major treatment modality is recanalization (percutaneous transluminal angioplasty with or without stent implantation). The cumulative 1-, 5-, and 10-year primary patency rates and survival rates are reported to be excellent or satisfactory, but the long-term outcome of patients with restenosis (the most common complication after recanalization) is unknown.

AIM

To explore the treatment strategy for restenosis in patients with Budd-Chiari syndrome after interventional therapy and to evaluate the long-term follow-up results.

METHODS

The clinical data and follow-up results of 60 patients with restenosis after interventional therapy from November 1983 to December 2013 were retrospectively analyzed.

RESULTS

Sixty patients with restenosis were retrospectively divided into a percutaneous transluminal angioplasty (PTA) group (40 patients) and a PTA + stent group (20 patients) according to the primary recanalization method. For the patients with restenosis in the PTA group, 13 refused treatment, and 27 received further treatment; among these patients, five had a second restenosis, two had a third restenosis, and one had a fourth restenosis. For the patients with restenosis in the PTA + stent group, nine refused treatment, ten received PTA alone, and the other received PTA + stent implantation. Among the patients who received further treatment, five had a second restenosis, three had a third restenosis, and one had a fourth restenosis. The 1-, 5-, 10-, 20-, and 25-year cumulative survival rates of the 38 patients who received further treatment after restenosis were 100%, 78.3%, 78.3%, 70.5%, and 70.5%, respectively; however, for the 22 patients who refused treatment, the survival rates were 72.7%, 45.9%, 30.6%, 10.2%, and unavailable, respectively (P < 0.001).

CONCLUSION

Long-term follow-up after interventional therapy is very important. Active treatment for patients with restenosis can improve prognosis, and minimally invasive treatment strategies for restenosis allows to obtain satisfactory results.

Hepatobiliary MR contrast agents are useful to diagnose hepatocellular carcinoma in patients with Budd-Chiari syndrome

BACKGROUND & AIMS

Hepatobiliary phase (HBP) images can discriminate between benign and malignant liver lesions, but it is unclear if this approach can be used in patients with Budd-Chiari syndrome (BCS). Thus, we aimed to assess the diagnostic utility of HBP images in patients with BCS.

METHODS

This retrospective study included all patients admitted to our institution with a diagnosis of BCS and focal liver lesions on hepatobiliary contrast agent-enhanced MR imaging (HBCA-MRI) from 2000 to 2019. MR images were reviewed by 2 radiologists blinded to the diagnosis of the lesions. Patient and lesion characteristics were recorded, focusing on HBP imaging features.

RESULTS

Twenty-six patients (mean 35 ± 11 years old [13-65]; 21 women [81%] 35 ± 12 years old [13-65]; 5 men [19%] 36 ± 10 years old [19-44]) with 99 benign liver lesions and 12 hepatocellular carcinomas (HCCs) were analyzed. Patients with HCC were significantly older than those with benign lesions (mean 50 ± 10 vs. 33 ± 9 years old, p = 0.003), with higher alpha-fetoprotein (AFP) levels (3/4 [75%] vs. 1/22 [5%] with AFP >15 ng/ml, p <0.001). Homogeneous hypointense signals were identified on HBP in 14 lesions, including 12/12 (100%) HCCs, and 2/99 (2%) benign lesions (p <0.001). Most benign liver lesions showed either peripheral (n = 52/99 [53%]) or homogeneous hyperintensity (n = 23/99 [23%]) on HBP. Lesions with signal hypointensity on HBP in patients with AFP serum levels >15 ng/ml were all HCCs.

CONCLUSION

Most benign lesions showed homogeneous or peripheral hyperintensity on HBP images while all HCCs were homogeneously hypointense. HBP images are helpful to differentiate between benign lesions and HCCs and outperform other sequences. They should be systematically acquired for the characterization of focal lesions in patients with BCS.

LAY SUMMARY

Hepatobiliary phase imaging is an approach that has recently been shown to discriminate between benign and malignant lesions in the liver. However, it was not known whether this imaging approach could be used effectively in patients with Budd-Chiari syndrome. Herein, we have shown that hepatobiliary phase imaging appears to be useful for differentiating between benign and malignant liver lesions in patients with Budd-Chiari syndrome.

Hereditary hemorrhagic telangiectasia: how to efficiently detect hepatic abnormalities using ultrasonography

INTRODUCTION

Hereditary hemorrhagic telangiectasia (HHT) is a multiorgan genetic angiodysplastic affection characterized by visceral vascular malformations. It affects mainly the brains, lungs, gastrointestinal tract, and nasal mucosa. Unlike those organs, hepatic involvement, although very frequently occurring, is insufficiently recognized, mainly because of the complex vascular structure of this organ. Thus, treating HHT patients requires a solid understanding of these hepatic anomalies. It is especially important for any general clinicians to be able to recognize clinical findings in HHT, which leads to a high suspicion of HHT and have an index of suspicion for liver abnormalities of HHT. For this purpose, keen awareness of clinical as well as hepatic sonographic (US) findings is paramount.

AIM

The aim of this review is to summarize previously reported findings on the hepatic US through a thorough analysis of related articles, and to (a) determine the role of US in the diagnosis of hepatic involvement in HHT patients and (b) propose the most simple and easy way to detect HHT-related abnormalities during routine US examinations.

CONCLUSION

Hepatic US serves to diagnose the detailed complex hepatic changes typical of HHT, and contributes to increased diagnostic confidence of hepatic changes in HHT patients, with the most simple way not to overlook HHT-related abnormalities being to find hepatic artery dilatation.

Venous Thrombosis and Hypercoagulability in the Abdomen and Pelvis: Causes and Imaging Findings

Venous thromboembolism (VTE), which includes deep venous thrombosis and pulmonary embolism, is a significant cause of morbidity and mortality. In recent decades, US, CT, and MRI have surpassed catheter-based angiography as the imaging examinations of choice for evaluation of vascular structures and identification of thrombus owing to their ready availability, noninvasive nature, and, in the cases of US and MRI, lack of exposure to ionizing radiation. As a result, VTE and associated complications are commonly identified in day-to-day radiologic practice across a variety of clinical settings. A wide range of hereditary and acquired conditions can increase the risk for development of venous thrombosis, and many patients with these conditions may undergo imaging for unrelated reasons, leading to the incidental detection of VTE or one of the associated complications. Although the development of VTE may be an isolated occurrence, the imaging findings, in conjunction with the clinical history and vascular risk factors, may indicate a predisposing condition or underlying diagnosis. Furthermore, awareness of the many clinical conditions that result in an increased risk of venous thrombosis may aid in detection of thrombus and any concomitant complications. For these reasons, it is important that practicing radiologists be familiar with the multimodality imaging findings of thrombosis, understand the spectrum of diseases that contribute to the development of thrombosis, and recognize the potential complications of hypercoagulable states and venous thrombosis. Online DICOM image stacks and supplemental material are available for this article. ^©RSNA, 2020.

An elderly man with progressive focal nodular hyperplasia

Patients with focal nodular hyperplasia (FNH) develop benign hepatocellular nodules. FNH most frequently occurs in young women. There are no reports of the onset of FNH in elderly men. We report a case of FNH in an elderly man, whose nodules increased in number and size. The patient underwent surgery for carcinoma of the left renal pelvis at 69 years of age; no liver masses were noted on yearly follow-up contrast-enhanced computed tomography (CECT). Ten years later, CECT revealed a hepatic mass, and magnetic resonance imaging suggested FNH. The nodules increased in number and size in subsequent follow-up examinations.

Current knowledge in pathophysiology and management of Budd-Chiari syndrome and non-cirrhotic non-tumoral splanchnic vein thrombosis

Budd-Chiari syndrome and non-cirrhotic non-tumoral portal vein thrombosis are 2 rare disorders, with several similarities that are categorized under the term splanchnic vein thrombosis. Both disorders are frequently associated with an underlying prothrombotic disorder. They can cause severe portal hypertension and usually affect young patients, negatively influencing life expectancy when the diagnosis and treatment are not performed at an early stage. Yet, they have specific features that require individual consideration. The current review will focus on the available knowledge on pathophysiology, diagnosis and management of both entities.

Budd-Chiari Syndrome and hepatic regenerative nodules: Magnetic resonance findings with emphasis of hepatobiliary phase

Budd-Chiari syndrome (BCS) is a disorder with numerous causes that is a result of hepatic outflow obstruction, in the absence of right heart failure or constrictive pericarditis. Acute Budd-Chiari syndrome is uncommon and clinically characterized by ascites, hepatomegaly, and hepatic insufficiency. In the majority of cases, patients present with chronic BCS, showing a dysmorphic liver disease with variable fibrosis deposition. In chronic Budd-Chiari syndrome, hepatocellular carcinoma (HCC) and benign regenerative nodules (called large regenerative nodules or FNH-like lesions) have been described in the literature. Very few studies have reported magnetic resonance imaging (MRI) findings about these nodules, using hepatobiliary contrast medium. The aim of our review is to describe the magnetic resonance imaging findings of hepatic regenerative nodules in BCS, with emphasis on the hepatobiliary phase, and to compare the imaging features of benign nodules with those of HCC.

Liver involvement in hereditary hemorrhagic telangiectasia

Liver vascular malformations (VMs) in hereditary hemorrhagic telangiectasia (HHT) are typically diffuse and can evolve from small telangiectasias to large arteriovenous malformations, with various stages of severity. Doppler US is the ideal first-line investigation for the assessment of liver VMs in HHT due to its safety, tolerability, low costs, and accuracy for the detection of liver VMs. The caliber, course, and flow characteristics in the hepatic artery, portal vein, and hepatic vein as determined by Doppler US, together with parenchymal abnormalities, support the diagnosis of liver VMs in HHT and their severity staging. When Doppler US expertise is lacking or an assessment of HHT patients with symptoms/signs suggestive of complicated liver VMs is required, particularly if OLT is considered, multiphase CT or MRI is suitable to investigate symptomatic liver VMs. Liver biopsy is neither necessary for the diagnosis of hepatic VMs related to HHT nor should be considered in HHT patients with liver mass/es suggestive of focal nodular hyperplasia.

Cirrhosis regression: extrahepatic angiogenesis and liver hyperarterialization persist

Data on the consequences of cirrhosis regression on portal hypertension and on splanchnic and systemic hemodynamic are scarce. Previous studies have reported a decrease in hepatic venous pressure gradient following antiviral treatment in patients with hepatitis B or C related cirrhosis. However, these studies did not investigate splanchnic and systemic hemodynamic changes associated with virus control. To fill this gap in knowledge, in a recent issue of Clinical Science, Hsu et al. (vol. 132, issue 6, 669-683) used rat models of cirrhosis induced by thioacetamide and by bile duct ligation and provided a comprehensive analysis of the effects of cirrhosis regression on splanchnic and systemic hemodynamics. They observed a significant reduction in portal pressure accompanied by a normalization of systemic hemodynamic (normal cardiac index and systemic vascular resistance) and a decrease in intrahepatic vascular resistance. No change in extrahepatic vascular structures were observed despite normalization of collateral shunting, meaning that portosystemic collaterals persist but are not perfused. One intriguing part of their results is the only marginal effect of cirrhosis regression on liver hyperarterialisation. This result suggests that changes in splanchnic hemodynamic features induced by cirrhosis remain when hepatic vascular resistance decreases, raising the hypothesis of an autonomous mechanism persisting despite regression of intrahepatic vascular resistance. Microbiota changes and bacterial translocation might account for this effect. In conclusion cirrhosis regression normalizes systemic hemodynamics, but some splanchnic hemodynamic changes persist including extrahepatic angiogenesis and liver hyperarterialization.

Hepatocellular nodules in vascular liver diseases

Hepatocellular nodules have been recognized in vascular liver diseases for a long time and mostly described and studied in the imaging literature. Some confusions in their identification and overlap in their definitions exist, especially in this specific clinical context. Pathology descriptions report the development of nodular regenerative hyperplasia, large regenerative nodule, and focal nodular hyperplasia, as adaptive responses of the liver parenchyma to the modified blood flow. True neoplastic hepatocellular nodules such as hepatocellular adenoma and hepatocellular carcinoma can also appear, mainly in Budd-Chiari syndrome, and have to be correctly diagnosed. This is more difficult for the radiologist in these diseased livers, leading more frequently to perform liver biopsies. We describe the histology of each type of well-differentiated hepatocellular nodules and provide some clues for their differential diagnosis. A review of the literature gives an historical perspective of the problem and enlightens the frequency and the subtypes of hepatocellular nodules found in the most common vascular liver diseases.