Pictorial review. Hepatic vascular shunts: embryology and imaging appearances

Improvement of liver histology in hepatic sarcoidosis due to treatment with corticosteroids and ursodeoxycholic acid: a case report

We report the case of a 48-year-old male with a history of pulmonary and ocular sarcoidosis. Non-caseating granulomas, identified histologically, are the most characteristic manifestation of sarcoidosis. Hepatic sarcoidosis is difficult to diagnose using radiological imaging. In the patient reported in this study, ultrasound and contrast-enhanced computed tomography scans identified multiple intra-abdominal lymphadenopathies, with evidence of liver and splenic infiltrations. The first liver biopsy revealed non-caseating granulomatous hepatitis consistent with hepatic sarcoidosis. The patient was treated with ursodeoxycholic acid (UDCA), but his laboratory parameters did not improve. Prednisone was initiated at a dose of 30 mg daily and slowly tapered. At a dose of 12.5 mg daily, marked improvements in the fibrotic and sarcoid-like lesions were noted at the second biopsy. A third biopsy was performed, with the patient on a prednisone taper of 5 mg/day showed mild fibrous expansion in the portal tracts and mild parenchymal necro-inflammatory lesions. However, overall, fibrosis marker levels remained stable over the course of treatment. A fourth biopsy was performed after a 5-year course of 5 mg/day prednisone. This revealed minimal lobular inflammation without fibrosis. Thus, treatment of this patient with corticosteroids and UDCA resulted in marked improvements in his biochemical and histological parameters.

The Portal Vein: A Comprehensive Review

Radiologists are familiar with the appearances of a normal portal vein; variations in its anatomy are commonplace and require careful consideration due to the implications for surgery. These alterations in portal vein anatomy have characteristic appearances that are clearly depicted on CT, MR, and US images. Similarly, there are numerous congenital and acquired disorders of the portal vein that are deleterious to its function and can be diagnosed by using imaging alone. Some of these conditions have subtle imaging features, and some are conspicuous at imaging but poorly understood or underrecognized. The authors examine imaging appearances of the portal vein, first by outlining the classic and variant anatomy and then by describing each of the disorders that impact portal vein function. The imaging appearances of portal vein abnormalities discussed in this review include (a) occlusion from and differentiation between bland thrombus and tumor in vein and the changes associated with resultant hepatic artery buffer response changes, cavernous transformation of the portal vein, and portal biliopathy; (b) ascending thrombophlebitis of the portal vein (pylephlebitis); (c) portal hypertension and its causes and sequelae; (d) the newly described disease entity portosinusoidal vascular disorder; and (e) intra- and extrahepatic shunts of the portal system, both congenital and acquired (including Abernethy malformations), and the associated risks. Current understanding of the pathophysiologic processes of each of these disorders is considered to aid the approach to reporting. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Portal Vein Variations, Clinical Correlation, and Embryological Explanation: A Review Article

Portal vein (PV) is a large vein that collects blood from the abdominal part of gall bladder, pancreas, alimentary tract, and spleen and transports to the liver. One of the parts of the extraembryonic venous system, the vitelline veins, is where PV starts. In about five weeks of gestation, a venous plexus is formed, and variations in this plexus lead to portal variance. The junction of superior mesenteric and splenic veins is typically where the vein begins to network. There are five types of branching patterns of the right PV: conventional branching, trifurcation branching, early branching, separate segment 7 branching, and separate segment 6 branching. To perform pancreatic, duodenal, and liver surgeries, knowledge of variations in PV formation is important. For surgical and interventional operations to be accurate, it is crucial to understand the architecture of the PV and its anomalies. As distinct regions of the brain connect with one another, portal architecture is frequently observed in imaging investigations. Portal hypertension is characterized as an increase in blood pressure in the portal venous system (PVS) in the context of severe liver disease, such as cirrhosis. Non-invasive methods for examining the anatomy and anomalies of the PV include ultrasound, computed tomography (CT), and magnetic resonance (MR). There are many abnormalities of PVS that have been discussed in the articles such as Congenital PV Absence; PV Branches Congenitally Grow in Structure; Hypoplasia, Atresia, and Stenosis of the PV; and Portosystemic Shunts.

Vessel network extraction and analysis of mouse pulmonary vasculature via X-ray micro-computed tomographic imaging

In this work, non-invasive high-spatial resolution three-dimensional (3D) X-ray micro-computed tomography (μCT) of healthy mouse lung vasculature is performed. Methodologies are presented for filtering, segmenting, and skeletonizing the collected 3D images. Novel methods for the removal of spurious branch artefacts from the skeletonized 3D image are introduced, and these novel methods involve a combination of distance transform gradients, diameter-length ratios, and the fast marching method (FMM). These new techniques of spurious branch removal result in the consistent removal of spurious branches without compromising the connectivity of the pulmonary circuit. Analysis of the filtered, skeletonized, and segmented 3D images is performed using a newly developed Vessel Network Extraction algorithm to fully characterize the morphology of the mouse pulmonary circuit. The removal of spurious branches from the skeletonized image results in an accurate representation of the pulmonary circuit with significantly less variability in vessel diameter and vessel length in each generation. The branching morphology of a full pulmonary circuit is characterized by the mean diameter per generation and number of vessels per generation. The methods presented in this paper lead to a significant improvement in the characterization of 3D vasculature imaging, allow for automatic separation of arteries and veins, and for the characterization of generations containing capillaries and intrapulmonary arteriovenous anastomoses (IPAVA).

Congenital Intrahepatic Arterioportal Fistula: Extremely Rare Cause of Melena and Chronic Diarrhea in Children

Congenital intrahepatic arterioportal fistulas are rare causes of presinusoidal portal hypertension in children. A rare case of arterioportal fistula in an infant is being reported. This report also highlights the need for long-term surveillance in such cases, despite being a benign pathology.

Canine intrahepatic portosystemic shunt insertion into the systemic circulation is commonly through primary hepatic veins as assessed with CT angiography

Congenital intrahepatic portosystemic shunts (IHPSS) in dogs are traditionally classified as right, left, or central divisional. There are few descriptive studies regarding the variation of IHPSS within these categories. This multicenter, analytical, cross-sectional study aimed to describe a large series of dogs with CT angiography (CTA) of IHPSS, hypothesizing that there would be variation to the existing classification. Ninety CTA studies were assessed for IHPSS type, insertion, and the relationship of the insertion to the primary hepatic veins. Ninety-two percent of IHPSS inserted into a primary hepatic vein (HV) or phrenic vein, 8% inserted directly into the ventral aspect of the intrahepatic caudal vena cava. The most common IHPSS type was a single right divisional (44%), including those inserting via the right lateral HV or the caudate HV. Left divisional IHPSS (33%) inserted into the left HV or left phrenic vein. Central divisional IHPSS (13%) inserted into the quadrate HV, central HV, dorsal right medial HV, or directly into the ventral aspect of the intrahepatic caudal vena cava. Multiple sites of insertion were seen in 9% of dogs. Within left, central, and right divisional types, further subclassifications can therefore commonly be defined based on the hepatic veins with which the shunting vessel communicates. Relating IHPSS morphology to the receiving primary HV could make IHPSS categorization more consistent and may influence the type and method of IHPSS attenuation recommended.

Quantitative analysis of hepatic macro- and microvascular alterations during cirrhogenesis in the rat

Cirrhosis represents the end-stage of any persistent chronically active liver disease. It is characterized by the complete replacement of normal liver tissue by fibrosis, regenerative nodules, and complete fibrotic vascularized septa. The resulting angioarchitectural distortion contributes to an increasing intrahepatic vascular resistance, impeding liver perfusion and leading to portal hypertension. To date, knowledge on the dynamically evolving pathological changes of the hepatic vasculature during cirrhogenesis remains limited. More specifically, detailed anatomical data on the vascular adaptations during disease development is lacking. To address this need, we studied the 3D architecture of the hepatic vasculature during induction of cirrhogenesis in a rat model. Cirrhosis was chemically induced with thioacetamide (TAA). At predefined time points, the hepatic vasculature was fixed and visualized using a combination of vascular corrosion casting and deep tissue microscopy. Three-dimensional reconstruction and data-fitting enabled cirrhogenic features to extracted at multiple scales, portraying the impact of cirrhosis on the hepatic vasculature. At the macrolevel, we noticed that regenerative nodules severely compressed pliant venous vessels from 12 weeks of TAA intoxication onwards. Especially hepatic veins were highly affected by this compression, with collapsed vessel segments severely reducing perfusion capabilities. At the microlevel, we discovered zone-specific sinusoidal degeneration, with sinusoids located near the surface being more affected than those in the middle of a liver lobe. Our data shed light on and quantify the evolving angioarchitecture during cirrhogenesis. These findings may prove helpful for future targeted invasive interventions.

Prenatal diagnosis of intra hepatic arterio venous fistula: case report and review of the literature

AIM

To describe the prenatal features and management of a congenital intra hepatic fistula.

MATERIAL AND METHODS

Case report Results: Congenital intra hepatic fistula are extremely rare. The prenatal ultrasound seiology is described.

CONCLUSION

Prenatal diagnosis of these anomalies may improve pre and post natal management.

Congenital Extrahepatic Portosystemic Shunt (Abernethy Malformation Type Ib) With Associated Hepatocellular Carcinoma: Case Report and Literature Review

Abernethy malformation, also termed congenital portosystemic shunt and congenital absence of portal vein is the result of malformation of the splanchnic venous system. Congenital portosystemic shunts are divided into extra- and intrahepatic shunts. Two shunts have been defined: Type I is characterized by the complete diversion of portal blood into the vena cava with an associated congenital absence of the portal vein. Type II is defined by an intact but diverted portal vein through a side-to-side, extrahepatic connection to the vena cava. The clinical manifestations of Abernethy malformation are diverse with a typical presentation consisting of hypoxia and hepto-pulmonary syndrome. Histologically, focal nodular hyperplasia, nodular regenerative hyperplasia, liver adenoma, hepatoblastoma, and hepatocellular carcinoma have all been reported. Herein, we report a case of Abernethy malformation, type Ib, in a 12-month-old male who was found to have a small hepatocellular carcinoma at the time of explant. The immunohistochemical characteristics in relation to the genetic aspects are discussed. To our knowledge, this is the first reported case of hepatocellular carcinoma developing in a patient who is under the age of 5 years with Abernethy malformation.

Altered Doppler flow patterns in cirrhosis patients: an overview

Doppler ultrasonography of the hepatic vasculature is an integral part of evaluating precirrhotic and cirrhotic patients. While the reversal of the portal venous flow is a well-recognized phenomenon, other flow patterns, although not as easily understood, may play an important role in assessing the disease status. This article discusses the different characteristic flow patterns observed from the portal vein, hepatic artery, and hepatic vein in patients with liver cirrhosis or related complications and procedures. Knowledge of these different flow patterns provides additional information that may reinforce the diagnosis of cirrhosis, help in staging, and offer prognostic information for determining the direction of therapy. Doppler ultrasonography is invaluable when liver transplantation is being considered and aids in the diagnosis of cirrhosis and portal hypertension.

Rare, spontaneous trans-splenic shunt and intra-splenic collaterals with attendant splenic artery aneurysms in an adult patient with compensated cirrhosis and portal hypertension

We present a rare case of spontaneous trans-splenic shunt and intra-splenic collaterals in a patient with liver cirrhosis and portal hypertension. The shunt and presence of cirrhosis and portal hypertension was incidentally detected by abdominal computed tomographic imaging during evaluation for abdominal pain. There has been a single report on the presence of trans-splenic shunt in two children with extra-hepatic portal venous obstruction but no cases that report intra-splenic collaterals: to the best of our knowledge, this is the first reported case of spontaneous trans-splenic shunt in the presence of intra-splenic collaterals and incidental multiple splenic artery aneurysms that developed in an adult with compensated cirrhosis and portal hypertension.