Focal nodular hyperplasia-like lesions in patients with cavernous transformation of the portal vein: prevalence, MR findings and natural history

Assessment of drainage vein of focal nodular hyperplasia using contrast-enhanced ultrasound

PURPOSE

Identification of drainage vessels is useful for differential diagnosis of hepatic tumors. Direct drainage to the hepatic vein has been reported to occur in focal nodular hyperplasia (FNH), but studies evaluating the drainage veins of FNH are limited. We aimed to investigate the detection rate of the FNH drainage vein and the factors related to visualization of the drainage vein on contrast-enhanced ultrasound (CEUS).

METHODS

Fifty consecutive patients with 50 FNH lesions were retrospectively evaluated in this study. We calculated and compared the detection rate of the FNH drainage vein on CEUS, contrast-enhanced magnetic resonance imaging (CEMRI), and contrast-enhanced computed tomography (CECT), and identified the factors correlated with visualization of the FNH drainage vein on CEUS by using multivariate logistic regression analyses.

RESULTS

Visualization of the drainage vein was confirmed in 31 of 50 lesions (62%) using CEUS, three of 44 lesions (6.8%) using CEMRI, and one of 18 lesions (5.6%) using CECT. The detection rate of the FNH drainage vein on CEUS was significantly higher than that on CEMRI and CECT (p < 0.001). Multivariate analysis identified lesion size (≥ 25 mm) and detection of the spoke-wheel pattern on Doppler US as independent factors for drainage vein detection in FNH.

CONCLUSION

Our study showed that rapid FNH drainage to the hepatic vein was observed at a relatively high rate on CEUS, suggesting that CEUS focusing on detection of drainage veins is important for diagnosing FNH.

Progress and clinical translation in hepatocellular carcinoma of deep learning in hepatic vascular segmentation

This paper reviews the advancements in deep learning for hepatic vascular segmentation and its clinical implications in the holistic management of hepatocellular carcinoma (HCC). The key to the diagnosis and treatment of HCC lies in imaging examinations, with the challenge in liver surgery being the precise assessment of Hepatic vasculature. In this regard, deep learning methods, including convolutional neural networksamong various other approaches, have significantly improved accuracy and speed. The review synthesizes findings from 30 studies, covering aspects such as network architectures, applications, supervision techniques, evaluation metrics, and motivations. Furthermore, we also examine the challenges and future prospects of deep learning technologies in enhancing the comprehensive diagnosis and treatment of HCC, discussing anticipated breakthroughs that could transform patient management. By combining clinical needs with technological advancements, deep learning is expected to make greater breakthroughs in the field of hepatic vascular segmentation, thereby providing stronger support for the diagnosis and treatment of HCC.

Prevalence of benign focal liver lesions and non-hepatocellular carcinoma malignant lesions in liver cirrhosis

Liver cirrhosis is associated with an increased risk of developing hepatocellular carcinoma (HCC). However, other benign and malignant liver lesions may co-exist or may be the only focal liver lesion (FLL) detected. Compared to HCC, comparatively little is known about the frequency and natural history of benign FLL in patients with established liver cirrhosis.This review analyses the prevalence and frequency of benign and malignant FLL others than hepatocellular carcinoma (HCC) in liver cirrhosis including imaging and autopsy studies. Understanding these data should be helpful in avoiding misdiagnoses.

Focal Nodular Hyperplasia-Like Lesions With Glypican-3 Positivity in Infancy

PURPOSE AND CONTEXT

Glypican-3 is often used to discriminate between neoplastic and nonneoplastic liver. In focal lesions, positivity may be considered suggestive of a malignancy such as hepatoblastoma. However, glypican-3 is also normally expressed in the immature liver. We present a series of 5 cases of focal nodular hyperplasia (FNH)-like lesions arising in very young patients with glypican-3 expression and highlight the challenges these lesions present in the differential diagnosis of hepatoblastoma.

METHODS

Cases were obtained from the files of 3 tertiary pediatric hospitals. Clinical data were obtained from the electronic medical record and histopathologic material including immunohistochemical stains were reviewed.

KEY RESULTS

Patients were aged 2 weeks to 6 months with peak AFP levels ranging from 88.6 to 204,696 ng/mL. Microscopically, all were variably demarcated hepatocellular lesions with cords of hepatocytes, marked sinusoidal dilatation, and occasional fibrous bands and areas reminiscent of central scar with bile ducts. No significant cytologic atypia or increased mitotic activity were present. All showed glypican-3 expression and were negative for nuclear beta-catenin with intact reticulin framework.

CONCLUSIONS

Our study highlights the pitfalls of evaluating focal liver lesions in infants when high AFP levels and glypican-3 expression may reflect immaturity rather than neoplasia.

Focal Liver Lesions other than Hepatocellular Carcinoma in Cirrhosis: Diagnostic Challenges

Liver cirrhosis is associated with regenerative nodules and an increased risk of developing hepatocellular carcinoma (HCC). However, other benign and malignant liver lesions may also occur. Differentiating the other lesions from HCC is important for further therapeutic decisions. This review discusses the characteristics of non-HCC liver lesions in cirrhosis and their consequent appearance on contrast-enhanced ultrasonography (CEUS) with consideration of other imaging. Knowledge of this data would be helpful in avoiding misdiagnoses.

The Role of Imaging in Portal Vein Thrombosis: From the Diagnosis to the Interventional Radiological Management

PURPOSE

To illustrate diagnostic and interventional imaging for the characterization and treatment of portal vein thrombosis (PVT).

INTRODUCTION

The broad spectrum of congenital and acquired PVT manifestations is illustrated, with a focus on the pediatric population; diagnostic and interventional imaging techniques are described.

DESCRIPTION

PVT frequently presents as an incidental finding at imaging in the screening for liver diseases or for other unrelated reasons. PVT can be classified based on: extension (intrahepatic, extrahepatic, involving the spleno-mesenteric tract, etc.); degree (partial or complete); onset (acute or chronic); and with or without cavernomatous transformation. This comprehensive review relies on the experience gained from a large series of congenital and acquired PVT in a referral center for pediatric and adult liver transplantation. Diagnostic and interventional imaging techniques are described, including: color-Doppler and contrast-enhanced Ultrasound; CT and MR angiography; retrograde portography; percutaneous transhepatic, transplenic, and transmesenteric portography; transjugular intrahepatic portosystemic shunt creation. Pre- and post-operative imaging assessment of the surgical meso-rex bypass is discussed. The description is enriched with an original series of pictorial imaging findings.

CONCLUSION

PVT is a clinical condition associated with significant morbidity and mortality. Diagnostic and interventional imaging plays a crucial role in both conservative and operative management.

Porto-sinusoidal vascular disorder

It is well established that portal hypertension can occur in the absence of cirrhosis, as reported in patients with immune disorders, infections and thrombophilia. However, similar histological abnormalities primarily affecting the hepatic sinusoidal and (peri)portal vasculature have also been observed in patients without portal hypertension. Thus, the term porto-sinusoidal vascular disorder (PSVD) has recently been introduced to describe a group of vascular diseases of the liver featuring lesions encompassing the portal venules and sinusoids, irrespective of the presence/absence of portal hypertension. Liver biopsy is fundamental for PSVD diagnosis. Specific histology findings include nodular regenerative hyperplasia, obliterative portal venopathy/portal vein stenosis and incomplete septal fibrosis/cirrhosis. Since other conditions including alcohol-related and non-alcoholic fatty liver disease, or viral hepatitis, or the presence of portal vein thrombosis may occur in patients with PSVD, their relative contribution to liver damage should be carefully assessed. In addition to histology and clinical diagnostic criteria, imaging and non-invasive tests such as liver and spleen stiffness measurements could aid in the diagnostic workup. The introduction of PSVD as a novel clinical entity will facilitate collaborative studies and investigations into the underlying molecular pathomechanisms encompassed by this term.

Benign Hepatic Nodules in Patients With Primary Extrahepatic Portal Vein Obstruction: Clinical and Magnetic Resonance Imaging Features

Background/objective

To retrospectively evaluate the magnetic resonance imaging (MRI) features of benign hepatic nodules in patients with extrahepatic portal vein obstruction (EHPVO) and assess predictable features for their development.

Methods

This retrospective observational study included 18 diagnosed patients of EHPVO who underwent contrast enhanced abdominal MRI at our Institute between June 2016 and May 2017, and who could be followed up for at least two years. The patients with liver nodules formed the study group (n = 8; 4 males, 4 females; mean age: 26.1 ± 10.9 years) and patients without liver nodules were controls (n = 10; 3 males, 7 females; mean age: 24.2 ± 15.1 years). Liver nodules were confirmed as benign by either biopsy or stability on follow up imaging. MRI features of liver nodules were assessed. Clinical details and imaging data of the study group were compared with controls to assess predictable features.

Results

There was no statistically significant difference in age, gender, clinical characteristics and upper gastrointestinal endoscopic findings between the study and control groups. The size of the lienorenal collateral, left renal vein and superior mesenteric vein were significantly larger in the study group (P < 0.05). In the study group, the majority had multiple hepatic nodules with most of them being isointense on T1 (18/35; 51.4%) and T2-weighted images (16/35; 45.7%) and showing restriction of diffusion (21/35; 60%). All (n = 35) lesions showed arterial phase hyperenhancement and none showed washout in the venous phase. The patients in the control group did not develop any liver nodules during the follow-up period.

Conclusion

Liver nodules in patients with EHPVO are likely to be benign and have characteristic MRI features. Significantly larger lienorenal collateral, left renal vein and superior mesenteric vein were associated with the development of these nodules.

Prevalence of Hepatic Space-Occupying Lesions Based on Sonographic Findings in Patients Referred to Guilan Cohort Center, Iran

Background: Early diagnosis of hepatic lesions can result in more successful treatment. Objectives: The present study aimed to diagnose hepatic space-occupying lesions by sonography in Guilan Cohort Center participants. Methods: In this cross-sectional prospective epidemiological research studies of Iranian adults (PERSIAN) Guilan cohort study (Sowme'eh Sara, Guilan, Iran) conducted in 2014 - 2017, the sample included 960 individuals of both genders, aged 35 - 60 years. A radiologist examined all individuals with sonography to determine hepatic space-occupying lesions. Demographical and clinical characteristics were recorded via a questionnaire. Data analysis was performed using SPSS software (version 16). Results: Only 2.3% of the patients were diagnosed with hepatic lesions such as hemangioma, hepatic cysts, and other lesions with frequencies of 1.1%, 0.8%, and 0.4%, respectively. Also, there was a significant relationship between gender and the presence of hepatic lesions (P < 0.05). The frequencies of hepatic lesions were 1.7% and 3.6% in men and women and 1.6%, 2.5%, and 4.4% in the age groups of 35 - 45, 45 - 55, and over 55 years, respectively. Conclusions: Hemangioma was the most common hepatic lesion diagnosed in ultrasonography examinations. Moreover, the only factor influencing the frequency of hepatic lesions was gender, which was found twice more in women than in men.

Focal Nodular Hyperplasia and Focal Nodular Hyperplasia-like Lesions

Focal nodular hyperplasia (FNH) is a benign lesion occurring in a background of normal liver. FNH is seen most commonly in young women and can often be accurately diagnosed at imaging, including CT, MRI, or contrast-enhanced US. In the normal liver, FNH frequently must be differentiated from hepatocellular adenoma, which although benign, is managed differently because of the risks of hemorrhage and malignant transformation. When lesions that are histologically identical to FNH occur in a background of abnormal liver, they are termed FNH-like lesions. These lesions can be a source of diagnostic confusion and must be differentiated from malignancies. Radiologists' familiarity with the imaging appearance of FNH-like lesions and knowledge of the conditions that predispose a patient to their formation are critical to minimizing the risks of unnecessary intervention for these lesions, which are rarely symptomatic and carry no risk for malignant transformation. FNH is thought to form secondary to an underlying vascular disturbance, a theory supported by the predilection for formation of FNH-like lesions in patients with a variety of hepatic vascular abnormalities. These include abnormalities of hepatic outflow such as Budd-Chiari syndrome, abnormalities of hepatic inflow such as congenital absence of the portal vein, and hepatic microvascular disturbances, such as those that occur after exposure to certain chemotherapeutic agents. Familiarity with the imaging appearances of these varied conditions and knowledge of their association with formation of FNH-like lesions allow radiologists to identify with confidence these benign lesions that require no intervention. Online supplemental material is available for this article. ^©RSNA, 2022.

Non-invasive diagnosis and follow-up of vascular liver diseases

Vascular disorders of the liver are rare diseases, some of which are diagnosed mainly with non-invasive tests and others by liver biopsy. Non-invasive methods can be used to diagnose and monitor these diseases. However, their evaluation needs to be performed by expert centers. Liver biopsy is needed each time there is an unexplained abnormality.

Hepatocyte-specific contrast-enhanced MRI findings of focal nodular hyperplasia-like nodules in the liver following chemotherapy in pediatric cancer patients

PURPOSE

We aimed to assess the MRI findings and follow-up of multiple focal nodular hyperplasia (FNH)- like lesions in pediatric cancer patients diagnosed by imaging findings.

METHODS

We retrospectively analyzed clinical data and MRI examinations of 16 pediatric patients, who had been scanned using gadoxetate disodium (n=13) and gadobenate dimeglumine (n=3). Hepatic nodules were reviewed according to their number, size, contour, T1- and T2-weighted signal intensities, arterial, portal, delayed and hepatobiliary phase enhancement patterns. Follow-up images were evaluated for nodule size, number, and appearance.

RESULTS

All 16 patients received chemotherapy in due course. Time interval between the initial diagnosis of cancer and detection of the hepatic nodule was 2-14 years. Three patients had a single lesion, 13 patients had multiple nodules. The median size of the largest nodules was 19.5 mm (range, 8-41 mm). Among 16 patients that received hepatocyte-specific agents, FNH-like nodules appeared hyperintense in 11 and isointense in 5 on the hepatobiliary phase. During follow-up, increased number and size of the nodules were seen in 4 patients. The nodules showed growth between 6-15 mm.

CONCLUSION

Liver MRI using hepatocyte-specific agents is a significant imaging method for the diagnosis of FNH-like lesions, which can occur in a variety of diseases. Lesions can increase in size and number in pediatric patients.

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.

Causes and Management of Non-cirrhotic Portal Hypertension​

PURPOSE OF THE REVIEW

Non-cirrhotic portal hypertension (NCPH) includes a heterogeneous group of conditions. The aim of this paper is to make an overview on the denominations, diagnostical features and management of porto-sinusoidal vascular disease (PSVD) and chronic portal vein thrombosis (PVT) being the main causes of NCPH in the Western world.

RECENT FINDINGS

The management of NCPH consists in the treatment of associated diseases and of portal hypertension (PH). PH due to PSVD or PVT is managed similarly to PH due to cirrhosis. TIPS placement and liver transplantation are considerable options in patients with refractory variceal bleeding/ascites and with progressive liver failure. Anticoagulation is a cornerstone both in the treatment of thrombosis in PSVD and in the prevention of thrombosis recurrence in patients with portal cavernoma. Physicians should be aware of the existence of PSVD and chronic PVT and actively search them in particular settings. To now, the management of portal hypertension-related complications in NCPH is the same of those of cirrhosis. Large cooperative studies on the natural history of NCPH are necessary to better define its management.

Portal cavernoma or chronic non cirrhotic extrahepatic portal vein obstruction

Chronic non cirrhotic extrahepatic portal vein obstruction (EHPVO) refers to the cavernomatous transformation of the portal vein (the so-called "portal cavernoma") which occurs following acute thrombosis of the portal vein in the absence of recanalization. In adults, EHPVO mainly occurs following thrombosis, while in children it may be related to congenital malformations and/or neonatal umbilical venous catheterization. However, 50% of the cases of EHPVO remain idiopathic [1]. Risk factors and associated diseases should be investigated (chapter 1). Indeed, the presence of a thrombophilic alteration, in particular myeloproliferative neoplasm impacts prognosis and determine a causal treatment.

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.

Hepatobiliary phase liver MR imaging findings after Oxaliplatin-based chemotherapy in cancer patients

OBJECTIVE

To describe Gd-EOB-DTPA-enhanced liver MR imaging findings in colon and rectal cancer patients who received Oxaliplatin.

CONCLUSION

Spectrum of hepatobiliary phase imaging findings include diffuse heterogeneous dysfunction, macronodular and micronodular FNH-like lesions, and coexistence of periportal increased liver function with FNH-like lesions. Differentiation of these benign lesions from metastasis is crucial to avoid biopsy in patients with colorectal cancers and may allow better understanding of sinusoidal obstruction syndrome pathophysiology and regenerative response of liver.

Benign and malignant hepatocellular lesions in patients with vascular liver diseases

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.

Liver Imaging Techniques: Recognition of Uveal Melanoma Metastases

Background

The liver is the most common site for metastases of several primary malignancies including uveal melanoma.

Methods

Review of imaging characteristics of incidental common benign liver lesions including hepatic cyst, hemangioma, focal nodular hyperplasia, and hepatic adenoma and contrasting them with uveal melanoma metastases.

Results

Benign hepatic lesions may be cystic or, if solid, relatively stable in size over time. For hepatic lesions larger than 10 mm in size, characteristic imaging features typically allow for confident diagnosis. When lesions are small (less than 10 mm), definitive characterization can be difficult. Moreover, lesions smaller than 10 mm can be difficult to biopsy under ultrasound or computed tomography (CT) guidance, and short-term follow-up will often be useful to assess for stability or progression. Overall, magnetic resonance imaging is more specific than CT scan and at least as sensitive as CT for detecting uveal melanoma liver metastases.

Conclusions

New multiple enhancing solid liver lesions should raise suspicion of uveal melanoma liver metastases. Discussion of challenging cases with the radiologist may be beneficial, as pertinent information such as size, location, and molecular prognostication status of the primary tumor can guide radiological interpretation of hepatic lesions.

Portal cavernoma cholangiopathy: diagnosis, imaging, and intervention

The term portal cavernoma cholangiopathy refers to the biliary tract abnormalities that accompany extrahepatic portal vein obstruction (EHPVO) and subsequent cavernous transformation of the portal vein. EHPVO is a primary vascular disorder of the portal vein in children and adults manifested by longstanding thrombosis of the main portal vein. Nearly all patients with EHPVO have manifestations of portal cavernoma cholangiopathy, such as extrinsic indentation on the bile duct and mild bile duct narrowing, but the majority are asymptomatic. However, progressive portal cavernoma cholangiopathy may lead to severe complications, including secondary biliary cirrhosis. A spectrum of changes is seen radiologically in the setting of portal cavernoma cholangiopathy, including extrinsic indentation of the bile ducts, bile duct stricturing, bile duct wall thickening, angulation and displacement of the extrahepatic bile duct, cholelithiasis, choledocholithiasis, and hepatolithiasis. Radiologists must be aware of this disorder in order to provide appropriate imaging evaluation and interpretation, to facilitate appropriate treatment and to distinguish this entity from its potential radiologic mimics.

Focal nodular hyperplasia: our experience of 53 Japanese cases

PURPOSE

Contrast-enhanced ultrasound (CEUS) is a very sensitive diagnostic tool in characterizing liver tumors. It is especially useful in the diagnosis of focal nodular hyperplasia (FNH) of the liver. According to the previous reports, FNH is common in young women, and it is usually diagnosed by MRI. The majority of the previous reports come from European countries, and a very few studies of large series designed to describe the clinical features in Japanese patients have been reported. The aim of this study was to (a) describe the clinical features in 53 patients (59 lesions) diagnosed with CEUS and (b) compare the data with those from the previous reports.

METHODS

The medical data from 53 patients diagnosed on the basis of typical CEUS findings at our institution and affiliated hospitals were reviewed, and their clinical data were analyzed.

RESULTS

(1) The medical data from 53 cases showed a slight male predilection, with 30 male cases (57 %) and 23 female cases (43 %), although the occurrence in both sexes was equal. FNH cases were distributed throughout all generations in both sexes, mostly concentrated in the age of 30-60 years old, and metabolic cases were more common in men than in women (4 vs 0). (2) The lesions were small (mean: 23 mm) and distributed throughout the whole liver. (3) Lesion size was not influenced by age in either sex. (4) A rapid draining to the hepatic vein was recognized in five out of 59 lesions (8 %).

CONCLUSIONS

Our data indicate that FNH occurs slightly more frequently in men than in women in Japan. It occurs also at any age in both sexes, but the mean lesion size was smaller in our series than in the previous reports. Metabolic disease was seen only in male FNH patients. A direct communication between the FNH lesion and the hepatic vein is diagnostically worth noting.

Prevalence of benign focal liver lesions: ultrasound investigation of 45,319 hospital patients

Purpose

The aim of the study was to determine the sonographic prevalence of benign focal liver lesions on the basis of a population of hospital patients.

Methods

The ultrasound results in a population of (n = 45,319) hospital patients over a period of 10 years were examined retrospectively and evaluated for the diagnosis of benign focal liver lesions [hepatic cysts, hepatic hemangioma, focal nodular hyperplasia (FNH), hepatic adenoma, and focal fatty sparing]. Results that were incomplete or ambiguous were excluded from this study.

Results

At least one of the lesions to be investigated was diagnosed in 15.1% (n = 6839) of the patients of the total population. The most commonly recorded lesion, with a total prevalence of 6.3% (n = 2839), was focal fatty sparing, followed by hepatic cysts with 5.8% (n = 2631). The prevalence of hepatic hemangioma was 3.3% (n = 1640), while that of FNH was 0.2% (n = 81) and that of hepatic adenoma was 0.04% (n = 19). An association between the occurrence of benign focal liver lesions and age was observed.

Conclusions

The calculated prevalence of benign focal liver lesions shows that on the fortuitous discovery of space-occupying lesions of the liver, first consideration should be given to focal fatty sparing, simple hepatic cysts and hemangiomas. The finding of a FNH or an adenoma is rarely a random discovery.

[Treatment of non-cirrhotic, non-tumoural portal vein thrombosis]

Thrombosis of the splenoportal axis not associated with liver cirrhosis or neoplasms is a rare disease whose prevalence ranges from 0.7 to 3.7 per 100,000 inhabitants. However, this entity is the second most common cause of portal hypertension. Prothrombotic factors are present as an underlying cause in up to 70% of patients and local factors in 10-50%. The coexistence of several etiological factors is frequent. Clinical presentation may be acute or chronic (portal cavernomatosis). The acute phase can present as abdominal pain, nausea, vomiting, fever, rectorrhagia, intestinal congestion, and ischemia. In this phase, early initiation of anticoagulation is essential to achieve portal vein recanalization and thus improve patient prognosis. In the chronic phase, symptoms are due to portal hypertension syndrome. In this phase, the aim of treatment is to treat or prevent the complications of portal hypertension. Anticoagulation is reserved to patients with a proven underlying thrombophilic factor.

[Natural history of portal cavernoma without liver disease. A single centre retrospective study of 32 cases]

PURPOSE

Portal cavernoma follows a chronic occlusion of the portal vein. The long-term consequences of portal cavernoma are not well known. The objective of this study was to report the aetiology of the portal cavernoma and its natural course after excluding liver diseases causes.

METHODOLOGY

A single centre retrospective study based on the data collected from the radiology department of the Clermont-Ferrand hospital was conducted from 2000 to 2011. All the patients for whom an imagery found a portal cavernoma have been looked for excluding the patients having a liver disease whatever the aetiology and the Budd-Chiari syndrome.

RESULTS

Thirty-two cases (18 women and 14 men) were selected. The mean age at diagnosis was 54.2 years and the mean follow-up period was 5.4 years. The discovery of a portal cavernoma was incidental for 8 cases. An aetiology was found for 24 cases: it was an haematological aetiology in 15 cases (10 myeloproliferative syndromes, 2 antiphospholid syndromes, 1 thalassemia major, 1 hyperhomocysteinemia, 1 prothrombin gene mutation), a general aetiology in 2 cases (1 coeliac disease, 1 pancreatic neoplasia), and a local inflammation in 7 cases. A dysmorphic aspect of the liver was noticed on medical imaging for 11 out of the 32 cases. A liver biopsy was performed in 4 patients and was normal for all of them. Sixteen patients developed oesophageal varices, 4 patients developed ascites, 3 developed asymptomatic biliary compression by the portal cavernoma, and the patient who had been followed for the longest time (15 years) developed an encephalopathy.

CONCLUSION

In addition to its underlying etiology, the prognosis of portal is mainly related to the occurrence of oesophageal varices that may develop during the follow-up of the patients.

Gadoxetic acid enhanced MRI for differentiation of FNH and HCA: a single centre experience

OBJECTIVES

Evaluation of enhancement characteristics of histopathologically confirmed focal nodular hyperplasias (FNHs) and hepatocellular adenomas (HCAs) with gadoxetic acid-enhanced MRI.

METHODS

Sixty-eight patients with 115 histopathologically proven lesions (FNHs, n=44; HCAs, n=71) examined with gadoxetic acid-enhanced MRI were retrospectively enrolled (standard of reference: surgical resection, n=53 patients (lesions: FNHs, n=37; HCAs, n=53); biopsy, n=15 (lesions: FNHs, n=7; HCAs, n=18)). Two radiologists evaluated all MR images regarding morphological features as well as the vascular and hepatocyte-specific enhancement in consensus.

RESULTS

For the hepatobiliary phase, relative enhancement of the lesions and lesion to liver enhancement were significantly lower for HCAs (mean, 48.7 (±48.4)%and 49.4 (±33.9) %) compared to FNHs (159.3 (±92.5) %; and 151.7 (±79) %; accuracy of 89%and 90 %, respectively; P<0.001). Visual strong uptake of FNHs vs. hypointensity of HCAs in the hepatobiliary phase resulted in an accuracy of 92 %. This parameter was superior to all other morphological and dynamic vascular criteria alone and in combination (accuracy, 54–85 %).

CONCLUSIONS

For differentiation of FNHs and HCAs by means of MRI, gadoxetic acid uptake in the hepatobiliary phase was found to be superior to all other criteria alone and in combination.

KEY POINTS

EOB-MRI is well suited to differentiate FNHs and hepatocellular adenomas. For this purpose hepatobiliary phase is superior to unenhanced and dynamic imaging. Hepatobiliary phase (peripheral) hyper- or isointensity is typical for FNH. Hepatobiliary phase hypointensity is typical for hepatocellular adenomas. EOB-MRI helps to avoid misinterpretations of benign hepatocellular lesions.

Clinical and imaging features of focal nodular hyperplasia in children

OBJECTIVE

The purpose of this article is to review the clinical and imaging features of focal nodular hyperplasia (FNH) developed in children.

MATERIALS AND METHODS

At a single institution, pediatric patients who underwent imaging studies and who had pathologically proven FNH were studied. Clinical characteristics, including presenting symptoms and signs and the presence of underlying disease, were reviewed from the medical records. Imaging features of FNHs, including the number, size, ultrasound echogenicity and vascularity, CT attenuation, MRI signal intensity and enhancement pattern, and the presence of a central scar, were evaluated.

RESULTS

Twenty-five patients (11 boys and 14 girls; median age, 8.6 years) were found to have a solitary (n = 23) or multiple (n = 2) FNH lesions with a mean size of 4.9 cm (range, 1-10 cm). Multiple lesions were associated with small size of the lesions and history of malignancy treated by chemotherapy. Most patients were asymptomatic (n = 22). Biliary atresia was the most common underlying disease (n = 5). On ultrasound, FNHs most commonly appeared to be isoechoic and hypervascular. On dynamic CT and MRI, strong enhancement on the arterial phase and becoming isoattenuated or of isointense signal intensity on the portal or delayed phase was common. A central scar was usually noted in large lesions in about half the cases.

CONCLUSION

Pediatric FNH is uncommon and usually is found incidentally in otherwise healthy children. However, it may occur in children who have underlying diseases, including biliary atresia. In addition, it can be encountered during surveillance of childhood cancer survivors with less common imaging features, including lack of a central scar and multiplicity.

Dynamic MRI findings and clinical features of benign hypervascular hepatic nodules in childhood-cancer survivors

OBJECTIVE

The purpose of this study is to investigate the dynamic MRI findings and clinical features of benign hypervascular hepatic nodules in childhood-cancer survivors.

MATERIALS AND METHODS

We reviewed dynamic MRI findings and clinical features in 15 patients who had been treated for childhood malignant solid tumors and in whom hypervascular hepatic nodules were later found on surveillance imaging by either CT or ultrasound (or both). The benign nature of the lesion was based on histologic examination or clinical and radiologic follow-up (or both).

RESULTS

Time between initial diagnosis of malignancy and detection of the hepatic nodule ranged from 4.5 to 13.5 years with the majority of the malignancies being neuroblastoma treated by high-dose chemotherapy and hematopoietic stem cell transplantation. A total of 43 nodules were detected, often multiple and small. Most of the lesions were isointense or slightly hyperintense on T2-weighted imaging and isointense or slightly hypointense on T1-weighted imaging. All nodules had intense enhancement on the arterial phase and were isointense or slightly hyperintense on the delayed phase. A central scar was seen in four. Additionally, hepatic hemosiderosis was noted in four patients, in whom all the lesions were hyperintense on both T1- and T2-weighted imaging.

CONCLUSION

Benign hypervascular hepatic nodules in survivors of childhood malignancy occur years after high-dose chemotherapy and hematopoietic stem cell transplantation. Dynamic MRI findings including intense arterial enhancement and absence of washout in the delayed phase are of great value in the differential diagnosis of these hepatic nodules.

Congenital portosystemic shunts associated with liver tumours

AIM

To evaluate the diagnosis and presentation of liver tumours in patients with congenital portosystemic shunts (CPS).

MATERIALS AND METHODS

Eight patients were diagnosed in Hôpital Beaujon as having CPS. All patients underwent Doppler ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), and histological examination of liver tumours. CPS were classified according to anatomy and the amount of portal flow deviated to the systemic circulation as: total, subtotal, or partial. Liver tumours were diagnosed by needle core biopsy (n = 5) or surgery (n = 3). Clinical follow-up was available in all patients but one (mean follow-up 36 months; range 1-5 years).

RESULTS

Six patients had total CPS, one patient had a subtotal CPS, and the last had a partial CPS. All patients presented with multiple liver nodules (range four to >15). The tumours were characterized as focal nodular hyperplasia (FNH; n = 4), FNH with hepatocellular adenoma (n = 2), and regenerative nodular hyperplasia (n = 2). In four of seven patients (57%) that had follow-up, tumours showed enlargement or new lesions appeared.

CONCLUSION

In this series of CPS patients, tumours were all benign, multiple, and of hepatocellular origin, and different tumours were present simultaneously in two patients. Tumour enlargement or new nodules were common during follow-up.

Hyperintense lesions on gadoxetate disodium-enhanced hepatobiliary phase imaging

OBJECTIVE

The purpose of this article is to illustrate various focal hepatic lesions that may show hyperintensity on hepatobiliary phase images on gadoxetate disodium-enhanced MRI.

CONCLUSION

Hyperintense lesions on gadoxetate disodium-enhanced MRI include focal nodular hyperplasia (FNH) or FNH-like nodules, hepatocellular adenoma, dysplastic nodules, and hepatocellular carcinoma. Understanding the contrast enhancement patterns on hepatobiliary phase images and other imaging findings is important to ensure correct diagnosis.