Radiological findings in ischaemic cholangiopathy

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.

Modified Appleby procedure for locally advanced pancreatic carcinoma: A primer for the radiologist

Pancreatic ductal adenocarcinoma (PDAC) is the most prevalent pancreatic neoplasm accounting for more than 90% of pancreatic malignancies. Surgical resection with adequate lymphadenectomy remains the only available curative strategy for patients with PDAC. Despite improvements in both chemotherapy regimen and surgical care, body/neck PDAC still conveys a poor prognosis because of the vicinity of major vascular structures, including celiac trunk, which favors insidious disease spread at the time of diagnosis. Body/neck PDAC involving the celiac trunk is considered locally advanced PDAC in most guidelines and therefore not eligible for upfront resection. However, a more aggressive surgical approach (i.e., distal pancreatectomy with splenectomy and en-bloc celiac trunk resection [DP-CAR]) was recently proposed to offer hope for cure in selected patients with locally advanced body/neck PDAC responsive to induction therapy at the cost of higher morbidity. The so-called "modified Appleby procedure" is highly demanding and requires optimal preoperative staging as well as appropriate patient preparation for surgery (i.e., preoperative arterial embolization). Herein, we review current evidence regarding DP-CAR indications and outcomes as well as the critical role of diagnostic and interventional radiology in patient preparation before DP-CAR, and early identification and management of DP-CAR complications.

Infarcts and ischemia in the abdomen: an imaging perspective with an emphasis on cross-sectional imaging findings

Infarcts and ischemia of abdominal organs may present with acute abdominal pain, and early diagnosis is crucial to prevent morbidity and mortality. Unfortunately, some of these patients present in poor clinical conditions to the emergency department, and imaging specialists are crucial for optimal outcomes. Although the radiological diagnosis of abdominal infarcts is often straightforward, it is vital to use the appropriate imaging modalities and correct imaging techniques for their detection. Additionally, some non-infarct-related abdominal pathologies may mimic infarcts, cause diagnostic confusion, and result in delayed diagnosis or misdiagnosis. In this article, we aimed to outline the general imaging approach, present cross-sectional imaging findings of infarcts and ischemia in several abdominal organs, including but not limited to, liver, spleen, kidneys, adrenals, omentum, and intestinal segments with relevant vascular anatomy, discuss possible differential diagnoses and emphasize important clinical/radiological clues that may assist radiologists in the diagnostic process.

Secondary sclerosing cholangitis: mimics of primary sclerosing cholangitis

Sclerosing cholangitis is a chronic cholestatic disease characterized by stricturing, beading, and obliterative fibrosis of the bile ducts. Sclerosing cholangitis is considered primary (PSC) if no underlying etiology is identified or secondary (SSC) if related to another identifiable cause. In this article, we will review the clinical features, pathogenesis, diagnosis, and imaging findings of PSC and SSC, with an emphasis on features that may aid in the distinction of these entities. We will also discuss various etiologies of SSC including recurrent pyogenic cholangitis, other infectious etiologies, ischemic damage, toxic insults, and immunologic, congenital, and miscellaneous causes, highlighting the unique imaging findings and clinical context of each diagnosis.

Prediction of bile duct injury after transarterial chemoembolization for hepatocellular carcinoma: Model establishment and verification

Objective

This study aimed to establish and validate a predictive model for bile duct injury in patients with hepatocellular carcinoma (HCC) after drug-eluting bead transarterial chemoembolization (DEB-TACE).

Methods

We retrospectively analyzed 284 patients with HCC treated with DEB-TACE at our hospital between January 2017 and December 2021, of whom 63 patients experienced postoperative bile duct injuries. Univariate and logistic multivariate regression analyses were performed to identify the risk factors for bile duct injury, as well as establish and internally validate the nomogram model. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve, calibration curve, Hosmer-Lemeshow goodness of fit test, decision curve analysis (DCA), and clinical impact curve (CIC) were used to assess the predictive power, clinical value, and practicability of the nomogram model.

Results

The incidence of bile duct injuries after DEB-TACE was 22.18% (63/284), with one injury occurring in every 2.86 sessions of DEB-TACE treatment. Univariate and logistic multivariate regression analyses indicated that a history of hepatectomy (odds ratio [OR]=2.285; 95% confidence interval [CI]=1.066-4.898; P<0.05), subjective angiographic chemoembolization endpoint level (OR=1.832; 95% CI=1.258-2.667; P<0.05), alkaline phosphatase (OR=1.005; 95% CI=1.001-1.010; P<0.05), and platelet count (OR=1.005; 95% CI=1.001-1.009; P<0.05) were independent risk factors for bile duct injury after DEB-TACE among patients with HCC. The risk nomogram model based on the above four variables was validated using the bootstrap method, showing consistency between the predicted and experimental values. Furthermore, the model performed well in the Hosmer-Lemeshow goodness-of-fit test (²=3.648; P=0.887). The AUC of this model was 0.749 (95% CI=0.682-0.817), with an overall accuracy of 69.01%, a positive predictive value of 73.02%, a negative predictive value of 67.87%, a sensitivity of 73.0%, and a specificity of 67.90%, suggesting that the nomogram model had good accuracy and discrimination. In addition, DCA and CIC revealed a high clinical value and practicability of the model.

Conclusion

Bile duct injury in patients with HCC treated with DEB-TACE is caused by multiple factors rather than a single factor. The nomogram prediction model used in this study had a good fitting degree and prediction efficacy, with high clinical value and practicability.

Hereditary Hemorrhagic Telangiectasia-A Case Series Experience from a Liver Transplant Center in Romania

Hereditary hemorrhagic telangiectasia (HHT) has significant morbidity due to multiorgan involvement and an unpredictable disease course. We analyzed the data of 14 patients diagnosed with HHT. The case series comprised 14 patients with a median age at presentation of 48 years old (41-74 years). In twelve patients (85.7%), the diagnosis was confirmed by using the Curacao Criteria. The most common reason for admission was epistaxis, with 9 patients (57%) presenting with nosebleed refractory to prolonged self-tamponade. The biochemical abnormalities identified were elevations in AP and gamma-GT; liver synthetic function was generally normal, even though 21% of patients had clinical or imaging findings for cirrhosis. Nosebleeds were the main reason for admission and significantly impacted quality of life through anemia and frequent hospital admissions. However, the visceral manifestations seemed to be more serious. The hepatic arteriovenous malformations (AVMs) appeared to remain asymptomatic or led to minimal changes for the majority of patients; some cases were associated with liver and biliary tract ischemia, necrosis leading to acute liver failure and even death. Hepatic AVMs can also lead to high-output heart failure due to arterio-venous shunting. The most frequent AVM was hepatic artery to hepatic vein, with secondary hepatic vein dilation and hemodynamic consequences.

Imaging features of COVID-19-associated secondary sclerosing cholangitis on magnetic resonance cholangiopancreatography: a retrospective analysis

Background

Despite emerging reports of secondary sclerosing cholangitis (SSC) in critically ill COVID-19 patients little is known about its imaging findings. It presents as delayed progressive cholestatic liver injury with risk of progression to cirrhosis. Diagnosis cannot be made based on clinical presentation and laboratory markers alone. Magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography (MRCP) can aid in the diagnosis. The aim of this study was to describe MRI/MRCP imaging features of COVID-19-associated SSC.

Results

Seventeen patients (mean age 60.5 years, 15 male) who underwent MRI/MRCP were included. All had been admitted to intensive care unit (ICU) (median duration of ICU stay 10 weeks, range, 2–28 weeks) and developed acute respiratory distress syndrome requiring mechanical ventilation. On imaging, all patients had intrahepatic bile duct strictures and 10 (58.8%) had associated upstream dilatation. Intrahepatic bile duct beading was seen in 14 cases (82.3%). Only one patient (5.9%) had extrahepatic bile duct stricturing. Patchy arterial phase hyperenhancement and high signal on T2- and diffusion-weighted images were seen in 7 cases (53.8%) and 9 cases (52.9%), respectively. Biliary casts were seen in 2 cases (11.8%). Periportal lymphadenopathy and vascular complications were not seen.

Conclusion

On MRI/MRCP, COVID-19-associated SSC presents with multiple intrahepatic bile duct strictures with or without upstream dilatation and intrahepatic bile duct beading. Surrounding hepatic parenchymal changes including alterations in enhancement and T2 signal are common. The extrahepatic biliary tree was typically spared and periportal lymphadenopathy was missing in all patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13244-022-01266-9.

MRI evaluation of bile duct injuries and other post-cholecystectomy complications

Laparoscopic cholecystectomy is one of the most common procedures performed each year and can be associated with various post-operative complications. Imaging is integral to diagnosis and management of patients with suspected cholecystectomy complications, and a thorough understanding of normal and abnormal biliary anatomy, risk factors for biliary injury, and the spectrum of adverse events is crucial for interpretation of imaging studies. Magnetic resonance cholangiography (MRC) enhanced with hepatobiliary contrast agent is useful in delineating biliary anatomy and pathology following cholecystectomy. In this article, we provide a protocol for contrast-enhanced MR imaging of the biliary tree. We also review the classification and imaging manifestations of post-cholecystectomy bile duct injuries in addition to other complications such as bilomas, retained/dropped gallstones, and vascular injuries.

The Risk Assessment and Clinical Research of Bile Duct Injury After Transcatheter Arterial Chemoembolization for Hepatocellular Carcinoma

Purpose

To retrospectively evaluate the risk factors and the clinical outcomes of bile duct injury after transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) and to evaluate factors that aid clinical detection and subsequent treatment of the injured bile duct.

Materials and Methods

All patients undergoing TACE for HCC were retrospectively reviewed for identification of bile duct injury. The clinical spectrum of all the patients analyzed including patients’ demographics, laboratory data, radiologic imaging and mode of treatment.

Results

From January 2015 to December 2017, a total of 21 patients (4.3%) out of 483 patients with 693 TACE procedures were identified to have bile duct injury at our single institution. There were 17 males and 4 females, with a mean age of 59.8±11.6 years (range 34–84). About 14.3% (3/21) patients show the high-density shadow around the bile duct wall in one week non-enhanced CT, and 76.2% (16/21) cases ALP>200 U/L, all these patients showed bile duct injury on the subsequent follow-up CT. Post-TACE follow-up blood biochemistry showed that alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and gamma glutamyl transpeptidase (GGT) increased significantly compared with pre-TACE level. The incidence of various types of bile duct injuries on CT was intrahepatic bile duct dilatation (57.1%), biloma (25.7%) and hepatic hilar biliary strictures (17.1%), respectively. Patients with prior hepatectomy as well as proximal arterial chemoembolization carried a higher risk of post-TACE bile duct injury in terms of microvascular damage to the peribiliary capillary plexus.

Conclusion

Bile duct injury complicating TACE is not caused by a single factor, but by a variety of factors, and is closely related to the microvascular compromise of the bile ducts and subsequent chronic biliary infection. Lipiodol deposited along the bile duct wall and the sharp rise of ALP>200 U/L in one week after TACE can predict bile duct injury and early intervention may prevent the occurrence of serious complications. The probability of bile duct injury in patients with prior hepatectomy and proximal arterial chemoembolization increases significantly.

Pathophysiology and Imaging Findings of Bile Duct Necrosis: A Rare but Serious Complication of Transarterial Therapy for Liver Tumors

Simple Summary

Bile duct necrosis (BDN) is rare but serious complication of transarterial therapy for liver tumors. During development of BDN, ischemia of the peribiliary vascular plexus (PBP) induces the disruption of the bile duct epithelial protection mechanism, causing necrosis of the surrounding tissue by the detergent action of exuded bile acids, and eventually a biloma forms. Once BDN starts, persistent tissue damage to the surrounding bile duct is induced by imbibed bile acids, and portal vein thrombosis may also be observed. On CT images, BDN shows similar findings to intrahepatic bile duct dilatation, and, therefore, it is sometimes misdiagnosed. Clinicians should be aware that although BDN and biloma can usually be treated conservatively, in the presence of symptoms such as moderate or severe infection or interval growth of the biloma, prompt treatment is essential to avoid lethal abscess formation and sepsis.

Abstract

Bile duct necrosis (BDN) with biloma formation is a type of ischemic bile duct injury that is one of the serious complications associated with transarterial therapies, such as transcatheter chemoembolization therapy (TACE), and radioembolization for hepatocellular carcinoma (HCC) and hepatic arterial infusion chemotherapy (HAIC) for metastatic liver cancer from colorectal carcinoma. In terms of the occurrence of BDN and subsequent biloma formation, ischemic injury to the peribiliary vascular plexus (PBP), the supporting vessel of bile duct epithelium, is thought to be intimately associated. In this paper, we first describe the anatomy, blood supply, and function of the intrahepatic bile duct, and then illustrate the pathophysiology of BDN, and finally present the imaging findings of BDN. Under the process of BDN formation, ischemia of the PBP induces the disruption of the bile duct epithelial protection mechanism that causes coagulation and fibrinoid necrosis of the surrounding tissue by the detergent action of exuded bile acids, and eventually a biloma forms. Once BDN occurs, persistent tissue damage to the surrounding bile duct is induced by imbibed bile acids, and portal vein thrombosis may also be observed. On pre-contrast and contrast-enhanced computed tomography (CT), BDN shows similar findings to intrahepatic bile duct dilatation, and, therefore, it is sometimes misdiagnosed. Differentiation of imaging findings on CT and ultrasound (US)/magnetic resonance (MR) imaging/MR cholangiopancreatography (MRCP) is important for correct diagnosis of BDN.