Anastomosis between the hepatic artery and the extrahepatic collateral or between extrahepatic collaterals: observation on angiography

Ischemic hepatitis with infectious endocarditis: A case report

A 58-year-old woman was admitted to Suzuka General Hospital with fever. She was diagnosed with infectious endocarditis based on the presence of anterior mitral leaflet vegetation on the echocardiography analysis and isolation of Pseudomonas guariconensis by blood culture. During treatment, the hepatic enzymes levels, including aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) were increased without any abdominal symptoms. Prolonged prothrombin time (PT) and prothrombin time international normalized ratio were observed, and acute hepatic failure was diagnosed. However, the hepatic injury resolved spontaneously with restoration of the PT value after the hepatic enzymes (AST, ALT, LDH and ALP) peaked. Diffusion-weighted imaging of hepatic magnetic resonance imaging showed diffuse high intensity of the entire liver except for part of the left lobe. The hepatic injury was diagnosed as ischemic hepatitis caused by embolization from the vegetation associated with infectious endocarditis. The recovery from hepatic ischemia was thought to be due to hepatic blood supply from extrahepatic collateral blood. After antibiotic treatment, the patient underwent resection of the vegetation on the anterior mitral valve leaflet. Hepatic artery occlusion is rare, but it may cause severe hepatic complications. During follow-up of infectious endocarditis, clinicians should be aware of the potential for whole organ ischemic damage caused by vessel occlusion, as well as hepatic ischemic damage.

Blood supply to the caudate lobe of the liver from the right inferior phrenic artery: observation by cone-beam computed tomography during arteriography

PURPOSE

To retrospectively evaluate blood supply to the caudate lobe of the liver from the right inferior phrenic artery (RIPA) using cone-beam computed tomography during arteriography (CBCTA-RIPA).

METHODS

CBCTA-RIPA examinations during transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) were collected from 2448 procedures in 787 patients. The exclusion criteria were (1) major artifacts, (2) TACE of hepatic arterial branches before performing CBCTA-RIPA, and (3) repeated CBCTA-RIPA studies in the same patient. Blood supply to three subsegments, the Spiegel lobe (SP), paracaval, and caudate process, was evaluated on CBCTA-RIPA images. The origins and routes of branches supplying the caudate lobe were also evaluated by three-dimensional vessel-tracking software.

RESULTS

Forty-seven CBCTA-RIPA examinations in 47 patients (38 with a history of TACE [repeated TACE group] and nine without it [initial TACE group]) were eligible, including five who had previously undergone hepatectomy. Seven had caudate lobe HCCs. Blood supply to the caudate lobe was demonstrated in 21 (44.7%) patients: in 50% (19/38) and 22.2% (2/9) of the repeated and initial TACE groups, respectively. The caudate arteries had previously been embolized in eight patients, the RIPA branch in three, and both in one. Forty-one proximal branches mainly supplied the dorsal part of the SP. All branches but five reached there through the inferior vena cava (IVC) ligament. The RIPA supplied eight of nine caudate lobe HCCs, totally (n = 7) or partially (n = 1).

CONCLUSION

The proximal RIPA branches mainly supply the dorsal SP through the IVC ligament, especially in the repeated TACE group.

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.

Ultraselective conventional transarterial chemoembolization: When and how?

Ultraselective conventional transarterial chemoembolization (cTACE), defined as cTACE at the most distal portion of the subsubsegmental hepatic artery, is mainly performed for hepatocellular carcinoma (HCC) ≤5 cm. Distal advancement of a microcatheter enables injection of a larger volume of iodized oil into the portal vein in the limited area under non-physiological hemodynamics. As a result, the reversed portal flow into the tumor through the drainage route of the tumor that occurs when the hepatic artery is embolized is temporarily blocked. By adding gelatin sponge slurry embolization, both the hepatic artery and portal vein are embolized and not only complete necrosis of can be achieved. Ultraselective cTACE can cure small HCCs including less hypervascular tumor portions and replace surgical resection and radiofrequency ablation in selected patients.

Hepatic Artery Resection for Bismuth Type III and IV Hilar Cholangiocarcinoma: Is Reconstruction Always Required?

OBJECTIVE

The objective of the study is to examine the feasibility of hepatic artery resection (HAR) without subsequent reconstruction (RCS) in specified patients of Bismuth type III and IV hilar cholangiocarcinoma.

METHODS

We retrospectively reviewed 63 patients who underwent hepatic artery resection for Bismuth type III and IV hilar cholangiocarcinoma. These patients were subsequently enrolled into two groups based on whether the artery reconstruction was conducted. Postoperative morbidity and mortality, and long-term survival outcome were compared between the two groups.

RESULTS

There were 29 patients in HAR group and 34 patients in the HAR + RCS group. Patients with hepatic artery reconstruction tended to have longer operative time (545.6 ± 143.1 min vs. 656.3 ± 192.8 min; P = 0.013) and smaller tumor size (3.0 ± 1.1 cm vs. 2.5 ± 0.9 cm; P = 0.036). The R0 resection margin was comparable between the HAR group and HAR + RCS group (86.2 vs. 85.3%; P > 0.05). Twelve patients (41.4%) with 24 complications in HAR group and 13 patients (38.2%) with 25 complications in HAR + RCS group were recorded (P = 0.799). The postoperative hepatic failure rate (13.8 vs. 5.9%) and postoperative mortality rate (3.4% vs. 2.9%) were also comparable between the two groups. In the HAR group, the overall 1-, 3-, and 5-year survival rates were 72, 41, and 19%, respectively; while in the HAR + RCS group, the overall 1-, 3-, and 5-year survival rates were 79, 45, and 25%, respectively (P = 0.928).

CONCLUSIONS

Hepatic artery resection without reconstruction is also a safe and feasible surgical procedure for highly selected cases of Bismuth type III and IV hilar cholangiocarcinoma.

Isolated Arteries Originating from the Intrahepatic Arteries: Anatomy, Function, and Importance in Intervention

Isolated hepatic arteries are defined as hepatic terminal arterioles that are not accompanied by portal venules or bile ductules and penetrate the liver parenchyma and distribute to the hepatic capsule and intrahepatic hepatic veins. Abundant communications exist between intra- and extrahepatic arteries through isolated arteries and capsular arterial plexus. They play a principal role in the development of subcapsular hemorrhage and arterial collateral formation following transcatheter arterial chemoembolization for liver cancers. The anatomy, function, and clinical importance of isolated hepatic arteries in interventional radiology, especially regarding subcapsular hemorrhage and arterial collateral formation, are highlighted in this article.

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%.

Efficacy of automated tumor-feeder detection software using cone-beam computed tomography technology in transarterial embolization through extrahepatic collateral vessels for malignant hepatic tumors

AIM

We evaluated the performance of automated tumor-feeder detection (AFD) software using cone-beam computed tomography technology in identifying tumor-feeders of extrahepatic collaterals.

METHODS

AFD was prospectively used in superselective transarterial chemoembolization (TACE) or embolization (TAE) of extrahepatic collaterals for 29 hepatocellular carcinomas and one liver metastasis (mean tumor diameter ± standard deviation, 28 ± 15.6 mm) in 25 patients. The detectability of extrahepatic tumor-feeders with non-selective digital subtraction angiography (DSA) and AFD was evaluated and compared using a χ(2) -test. Tumor response of target lesions in each patient at 2-3 months after treatment was evaluated using the modified Response Evaluation Criteria in Solid Tumors. Complications were also evaluated.

RESULTS

Of 46 tumor-feeders, non-selective DSA and AFD could identify 26 and 44, respectively (P < 0.001). Regarding the origin of tumor-feeders, both non-selective DSA and AFD could identify 14 of 15, six of seven and two of two tumor-feeders of the right inferior phrenic, omental and right renal capsular artery, respectively. In the cystic and left gastric or right colic artery, AFD could identify 13 of 13 and nine of nine tumor-feeders but non-selective DSA could identify only three of 13 and one of nine, respectively (P < 0.001). Complete response was obtained in 15 patients, partial response in six, stable disease in three and progressive disease in one. No severe complications developed except for right pleural effusion after embolization of the right inferior phrenic artery.

CONCLUSION

AFD has a sufficient ability to identify extrahepatic tumor-feeders and may improve the safety and local effects of TACE/TAE of extrahepatic collaterals.

Transcatheter arterial chemoembolization for hepatocellular carcinoma fed by the cystic artery: A report of 45 cases

AIM: To evaluate the safety, technical success rate, and effectiveness of transcatheter arterial chemoembolization (TACE) for unresectable hepatocellular carcinoma (HCC) fed by the cystic artery.

METHODS: Treatment of 45 tumors in 45 patients fed by the cystic artery was attempted with TACE. Thirty-six patients had previously undergone one to eight TACE sessions (mean, four sessions), and the duration after initiation of treatment of HCC was 4 to 69 mo (mean, 24). In 9 patients, parasitization of the cystic artery was revealed at initial angiography. TACE was performed only when the microcatheter could be inserted into the tumor feeding branch and the stain of the gallbladder wall disappeared. The therapeutic effects and complications were retrospectively analyzed.

RESULTS: Twenty-eight tumors were completely fed by the cystic artery and 17 were fed by both the hepatic artery and cystic artery. Attenuation or occlusion of the hepatic artery was observed in 60% (n = 27) of tumors. The tumor feeding branch arising from the cystic artery could be successfully embolized in 32 tumors (71%) of 32 patients without severe complications. Adequate iodized oil accumulation was achieved in 28 tumors (62%) of 28 patients. Local progression was observed in 6 (21%) of these 28 tumors treated by TACE alone during a mean follow-up period of 18 mo. Percutaneous therapy (n = 6), radiation (n= 4), and TACE after cholecystectomy (n = 3) were added for tumors with incomplete or unsuccessful TACE.

CONCLUSION: TACE via the cystic artery was safe and technically possible in 71% of patients. If adequate iodized oil accumulation is obtained, which was achieved in 62% of our patients, sufficient therapeutic effect may be expected.

Arterial blood supply to the caudate lobe of the liver from the proximal branches of the right inferior phrenic artery in patients with recurrent hepatocellular carcinoma after chemoembolization

PURPOSE

To evaluate the arterial blood supply to the caudate lobe of the liver from the proximal branches of the right inferior phrenic artery (RIPA) in patients with recurrent hepatocellular carcinoma after transcatheter arterial chemoembolization (TACE).

MATERIALS AND METHODS

Thirteen patients, including 10 who had a history of TACE of the caudate artery (A1), underwent TACE of the proximal RIPA branches. Iodized oil distribution was evaluated by computed tomography (CT) 1-week after TACE. Angiographic findings were also evaluated.

RESULTS

Previously embolized A1 was occluded (n = 15) or attenuated (n = 2). In one of three patients without A1 TACE, A1 was also attenuated. TACE was performed at the first branch of the proximal RIPA (n = 8), the first branch of the anterior branch (n = 6), and the first branch of the posterior branch (n = 1), respectively. Iodized oil was mainly distributed into the dorsal part of the Siegel lobe (SP) (n = 10), the caudate process (n = 1), and both (n = 2). In three of seven patients who had undergone serial RIPA angiography, RIPA parasitization to SP was suspected before A1 TACE.

CONCLUSION

The proximal RIPA branches mainly supply the SP when A1 is attenuated.

Inferior phrenic arteries: angiographic anatomy, variations, and catheterization techniques for transcatheter arterial chemoembolization

The inferior phrenic artery (IPA) is the most common extrahepatic collateral vessel to hepatocellular carcinoma (HCC); however, there are many anatomical variations in its origin and branches. In addition, the IPA is frequently reconstructed through several pathways, mainly through the retroperitoneal network, because of the occlusion of its orifice due to atherosclerosis or previous catheter manipulation. Infrequently, selective catheterization into the IPA is impossible even using a microcatheter, particularly in the IPA that originates from the proximal or distal portion of the celiac trunk or from the aorta with an acute angle. In this article, we describe anatomical variations of the IPA and catheterization techniques, such as a catheter with a large side hole and a catheter with a cleft, to facilitate catheterization into the IPA that is difficult using a conventional coaxial technique. Radiologists should have sufficient knowledge of such variations and catheterization techniques to perform transcatheter arterial chemoembolization for HCCs through the IPA effectively and safely.

The march of extrahepatic collaterals: analysis of blood supply to hepatocellular carcinoma located in the bare area of the liver after chemoembolization

The purpose of this study was to evaluate changes in vascular supply to hepatocellular carcinoma (HCC) located in the bare area of the liver in patients who were mainly treated with chemoembolization. Twenty-six patients with HCC showing a mean diameter of 3.1 +/- 1.4 cm (mean +/- standard deviation) were mainly treated with chemoembolization. All patients underwent 2.7 +/- 2.3 chemoembolization sessions over 40.1 +/- 25.2 months. Tumor feeding branches demonstrated in each chemoembolization session were retrospectively evaluated. Initially, 18 tumors (59.2%) were supplied by the hepatic artery (H) and 8 (30.8%) by both the hepatic and the extrahepatic arteries (H + C). Fourteen tumors (53.8%) recurred at the posterior aspect of the tumor and were supplied by H (n = 4), H + C (n = 5), and extrahepatic collaterals (C) (n = 5). Several tumors recurred despite repeated chemoembolization, and these were supplied by H (n = 1), H + C (n = 7), and C (n = 2) at the second recurrence, by H (n = 1), H + C (n = 2), and C (n = 3) at the third, by H + C (n = 2) and C (n = 2) at the fourth, by H + C (n = 2) and C (n = 2) at the fifth, and by H (n = 1) and C (n = 1) at the sixth. One tumor was supplied by H at the seventh and by H + C at the eighth recurrence. As the number of local recurrences increased, the feeding vessel shifted from H to C. Especially, the right inferior phrenic artery (IPA) and renal capsular artery (RCA) supplied the tumor early, while the small right RCAs, adrenal arteries, and intercostal and lumbar artery supplied late recurrences in turns. In conclusion, HCCs located in the bare area are frequently supplied by extrahepatic vessels initially, while recurrence after chemoembolization is mainly due to extrahepatic blood supply. The right IPA and RCA are common feeding vessels demonstrated early, while other extrahepatic collateral supply from the retroperitoneal circulation occurs in turns during the later course.