Blood supply of the main bile duct from the caudate artery and medial subsegmental artery of the hepatic artery: Evaluation using images obtained during transcatheter arterial chemoembolization for hepatocellular carcinoma

Radiological Vascular Anatomy of the Caudate Lobe of the Liver Required for Transarterial Chemoembolization of Hepatocellular Carcinoma

The caudate lobe is located between the bilateral hepatic lobes and is divided into three subsegments: the Spiegel lobe, paracaval portion, and caudate process. The caudate artery arises from various sites of the bilateral hepatic arteries as an independent branch, common trunk, or arcade. Extrahepatic arteries can enter the caudate lobe mainly by the right inferior phrenic artery. The caudate artery also supplies the main bile duct and posterior aspect of segment IV. Although catheterization into the caudate artery is occasionally difficult because of its small size and sharp angulation, selective embolization of a tumor feeder is a significant prognostic factor in patients with hepatocellular carcinoma originating there. Therefore, we should recognize the peculiarity of its vascular anatomy and should be familiar with catheterization and embolization techniques.

Complications Related to Transarterial Treatment of Hepatocellular Carcinoma: A Comprehensive Review

Currently, various types of transarterial treatments are performed for hepatocellular carcinoma from the early to advanced stages. Its indications and efficacy have been widely investigated. However, procedure-related complications have not been updated in the literature, although new types of transarterial treatments, such as drug-eluting bead transarterial chemoembolization and transarterial radioembolization, are common in daily practice. Herein, a comprehensive literature review was carried out, and complications were organized according to the organs affected and treatment modalities.

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.

Benign Biliary Stricture after Yttrium-90 Radioembolization for Hepatocellular Carcinoma

PURPOSE

To determine the frequency and possible causative factors of benign biliary stricture after radioembolization in patients with hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

This retrospective study comprised 232 patients with HCC who underwent yttrium-90 radioembolization between October 2015 and September 2019. Benign biliary stricture was defined as biliary ductal dilatation of segmental or lobar biliary ducts on follow-up images. Clinical and radiologic characteristics were compared using χ² test or independent t test.

RESULTS

Mean target perfused tissue dose was 224.6 Gy ± 106.8 (median, 205.7 Gy; range, 47.0-694.7 Gy). Of 232 patients, 15 (6.5%) had benign biliary stricture, which was detected from 3 weeks to 10.3 months (mean, 3.9 months; median, 3.2 months). Whereas 5 patients did not have any symptoms or signs associated with benign biliary stricture, 10 patients had cholangitis and/or laboratory abnormality requiring biliary drainage procedures and intravenous antibiotic therapy. Selective radioembolization through a caudate artery was performed in 55 (23.7%) patients. The incidence of benign biliary stricture was 16.4% (9/55) and 3.4% (6/177) in patients with and without selective radioembolization through a caudate artery, respectively (P = .002).

CONCLUSIONS

Benign biliary stricture following yttrium-90 radioembolization may be common among patients receiving selective treatment via a caudate artery.

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.

Selective Chemoembolization of Caudate Lobe Hepatocellular Carcinoma: Anatomy and Procedural Techniques

Transarterial chemoembolization is the most common treatment for unresectable hepatocellular carcinomas (HCCs). However, when an HCC is located in the caudate lobe, many interventional radiologists are reluctant to perform chemoembolization and percutaneous ablation owing to the tumor's complex vascular supply and deep location. With the advent of C-arm CT, rendering the three-dimensional display of the hepatic artery and detecting the tumor-feeding vessels are possible and can help guide interventional radiologists to the tumor. The common origins of the caudate artery include the right hepatic artery, left hepatic artery, right anterior hepatic artery, and right posterior hepatic artery. The origins of the tumor-feeding arteries of a caudate lobe HCC can vary depending on the tumor's subsegmental location. Caudate lobe HCCs are commonly fed by multiple caudate arteries that are connected. In addition, extrahepatic collateral arteries frequently supply recurrent tumors in the caudate lobe. The caudate artery can supply portal vein thrombi or biliary tumor thrombi in patients with HCC. Several techniques such as preshaping the microcatheter or using the shepherd's hook technique are needed to catheterize the caudate artery in complex cases. Although uncommon, bile duct stricture is a serious complication following selective chemoembolization through the caudate artery. Identification and catheterization of the caudate artery have become possible in most patients by using C-arm CT and a fine microcatheter system, respectively. The authors review the anatomy of the caudate artery with C-arm CT and describe basic technical considerations in selective chemoembolization for caudate lobe HCCs. Unusual circumstances that require catheterization and techniques used for catheterizing the caudate artery are also described. Online supplemental material is available for this article. ^©RSNA, 2019.

Excretion of necrotic hepatocellular carcinoma tissues into the biliary system after transcatheter arterial chemoembolization

AIM

To evaluate the incidence and condition of necrotic tumor excretion into the biliary system in patients with hepatocellular carcinoma (HCC) >5 cm treated with conventional transcatheter arterial chemoembolization (TACE).

METHODS

Eighty-three patients who underwent TACE for newly developed HCC >5 cm without an intraductal tumor thrombus and were followed-up by computed tomography for longer than 6 months were eligible. According to the location, the maximum tumors were divided into central (in contact with the left or right hepatic duct, n = 39) or peripheral (not in contact with them, n = 44). When high-density material in the biliary system that was not seen on pretreatment computed tomography was identified, it was determined as excreted necrotic tumor tissue containing iodized oil. The incidence, interval between TACE and occurrence of the necrotic tumor excretion, and clinical course were evaluated.

RESULTS

Tumor excretion into the biliary system was identified in nine (10.8%) patients with a central tumor (mean diameter, 85.0 ± 29.6 mm) 28-433 days (mean, 219.3 ± 128.2) after the initial TACE. In one patient, the necrotic tumor cast caused cholangitis 1203 days after the initial TACE, and was endoscopically removed. Infection of the embolized tumor developed in two cases and percutaneous drainage was carried out 105 and 158 days later, respectively.

CONCLUSIONS

Excretion of necrotic tumors into the biliary system after TACE was not rare in patients with centrally located HCC >5 cm. The detached tumor rarely caused symptoms and the communication between the tumor and bile duct caused the infection of tumors.

Semiquantitative prediction of early response of conventional transcatheter arterial chemoembolization for hepatocellular carcinoma using postprocedural plain cone-beam computed tomography

AIM

To investigate whether plain cone-beam computed tomography (CT) immediately after conventional transcatheter arterial chemoembolization (c-TACE) can help to predict tumor response semiquantitatively in patients with hepatocellular carcinoma (HCC).

METHODS

Analysis was carried out retrospectively on 262 targeted HCCs in 169 patients treated with c-TACE. Dynamic CT was performed at baseline and 1-4 months after c-TACE. Receiver-operating characteristic curve analysis was undertaken to evaluate whether voxel values of cone-beam CT could predict a complete response and to identify the cut-off value. Final tumor response assessment and early prediction using the retention pattern of iodized oil, the cut-off value of the density, and the combination of the cut-off density value and retention pattern of iodized oil in HCCs on postprocedural cone-beam CT were compared.

RESULTS

Complete response was obtained in 72.9% of lesions. According to the pattern of iodized oil uptake, the sensitivity, specificity, and accuracy for predicting complete response were 85.9%, 70.4%, and 81.7%, respectively by excellent uptake on cone-beam CT. The area under the curve was 0.86 with the optimal cut-off at a voxel value of 200.13. According to not only the density but also the homogeneity of iodized oil retention, the sensitivity, specificity, and accuracy values for predicting complete response were 86.4%, 95.8%, and 88.9%, respectively. The predictive accuracy was significantly better than that of the pattern of iodized oil retention only (P = 0.019).

CONCLUSION

The combination of density and visual estimate of homogeneity is superior to either alone in predicting tumor response of c-TACE in HCC patients.

Superselective Conventional Transarterial Chemoembolization for Hepatocellular Carcinoma: Rationale, Technique, and Outcome

Conventional transarterial chemoembolization with ethiodized oil and gelatin sponge (GS) particles is a standard technique for hepatocellular carcinoma. Ethiodized oil can temporarily block tumor sinusoids, portal venules, hepatic sinusoids, and arterial microcommunications. By adding GS embolization, strong ischemic effects not only on the tumor but also on the surrounding liver parenchyma can be achieved. Superselective conventional transarterial chemoembolization is mainly indicated for patients with Child-Pugh scores of 5-8, tumors ≤ 7 cm, and ≤ 5 lesions. According to a Japanese nationwide survey, the 5-year survival rate of patients with Child-Pugh class A and a single tumor was 52%.

Study of relationship between the blood supply of the extrahepatic bile duct and duct supply branches from gastroduodenal artery on imaging and anatomy

Background:

Liver transplantation has become the treatment of choice for patients with end-stage acute or chronic hepatic disease. Bile duct complications are common events after liver transplantation. The aim of this study was to evaluate the blood supply of the human bile duct and identify the underlying mechanisms of bile duct complications after liver transplantation.

Methods:

The duct supply branches from gastroduodenal artery and blood supply of extrahepatic bile duct system were re-evaluated through selective hepatic angiography from 600 patients. In addition, 33 cadavers were injected with latex casting material into the common hepatic artery, then the extrahepatic bile duct and the branches from the common hepatic artery were carefully dissected to visualize the gastroduodenal artery and its branching to the extrahepatic bile duct.

Results:

The bile duct artery arose from the branch of the gastroduodenal artery in 8.1% (49/600). Of these 49 individuals, the bile duct artery was supplied by the gastroduodenal artery (61.22%, 30/49), the proper hepatic artery (14.29%, 7/49), or both the gastroduodenal artery and the proper hepatic artery (24.49%, 12/49). In our study of 33 cadavers, the percentage that the bile duct artery arose from the gastroduodenal artery was 27.27%. The blood supply to the bile extrahepatic bile ducts was divided into different segments and formed longitudinal and arterial network anastomosed on the walls of the duct.

Conclusions:

There is a close relationship between the duct supply branches from gastroduodenal artery and the blood supplying patterns of the extrahepatic bile duct system. In liver transplant surgery, the initial part of the gastroduodenal artery is preferred to be preserved in the donor liver. It is of great significance to improve the success rate of operation and reduce complications.

Tracking Navigation Imaging of Transcatheter Arterial Chemoembolization for Hepatocellular Carcinoma Using Three-Dimensional Cone-Beam CT Angiography

PURPOSE

New tracking navigation imaging software was used to evaluate the usefulness of three dimensional (3D) CT angiography for transcatheter arterial chemoembolization (TACE) in patients with hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Fifty-two patients with 73 HCCs were enrolled in this study retrospectively. Rotational angiography was performed from the hepatic artery for evaluation of the tumor feeding vessels. Arteries feeding the tumor were traced automatically by adjusting the region of interest around the targeted tumor on axial and coronal images using tracking navigation imaging with 3D cone-beam CT angiography.

RESULTS

Using final selective angiographic findings as the gold standard, the detection of feeding vessels was 90.4% (66/73) for tracking navigation imaging and 50.7% (37/73) for celiac trunk angiography. This difference was statistically significant (Wilcoxon rank sum test, p < 0.001). The sensitivity, specificity, positive predictive value, and negative predictive value for the detection of feeding arteries were 97.1% (66/68), 80.0% (4/5), 98.5% (66/67), and 66.7% (4/6), respectively. The kappa coefficient had a value of 0.638 (95% CI: 0.471-0.805), which is considered to indicate a good degree of agreement. With the assistance of tracking navigation imaging, the disease control rate of TACE for HCC was 67.3% (35/52) according to the modified Response Evaluation Criteria in Solid Tumors. During follow-up periods of 1-11 months, 10 patients (19.2%) remained cancer-free after TACE.

CONCLUSION

Tracking navigation imaging with 3D cone-beam CT angiography should be useful for TACE in HCC patients with complicated feeding arteries.