Posterior Hepatic Artery Research Articles

Association of Early Bifurcation of Hepatic Artery With Arterial Injury in Right-Sided Living-Donor Hepatectomy: Retrospective Analysis of 500 Cases.

The aim of this study was to explore the incidence of early bifurcation of the right hepatic artery (RHA) and the right posterior hepatic artery (RPHA), which is crucial in right lobe graft (RLG) and right posterior sector graft (RPSG) procurement for living-donor liver transplantation. Early bifurcation of the hepatic artery tends to induce oversight of one of the bifurcated arteries and its injury in RLG/RPSG procurement. Unrecognizable on conventional 3-dimensional (3-D) images, its significance is underestimated. We enrolled 500 patients who underwent preoperative imaging for scheduled surgeries at two major transplant centers. All-in-one 3-D images consisting of the hepatic artery, portal vein, and bile duct were constructed. Early bifurcation of the RHA and the RPHA was defined as the arteries bifurcating proximal to the cutting line of the right hepatic duct and the right posterior duct, respectively. Early bifurcation of the RHA was seen in 11.3% of cases of an infra-portal RPHA and in 46.0% of cases of a supraportal RPHA ( P < 0.001). Early bifurcation of the RPHA was encountered in 35.3% of cases of an infra-portal RPHA, in no cases of a supra-portal RPHA, and in 100% of cases in which the arteries to segment 6/7 arose individually from the RHA. The overall incidence of early bifurcation was 19.9% for RHA and 43.6% for RPHA. Early bifurcation of the RHA and the RPHA is frequently encountered and requires caution for RLG/RPSG procurement. Special attention should be paid to supraportal RPHA for RLG procurement.

Quality of superior mesenteric and hepatic artery dissection in robotic pancreatoduodenectomy for pancreatic cancer.

This video manuscript by Ikoma and colleagues demonstrates their approach to the superior mesenteric artery and hepatic artery periadventitial dissection. The quality of superior mesenteric artery and hepatic artery dissections should be maintained in robotic pancreatoduodenectomy when performed for pancreatic cancer, to provide the best possible oncological outcomes.

Extended left trisegmentectomy combined with the three main hepatic veins ligation and inferior vena cava (IVC) resection for intrahepatic cholangiocarcinoma (ICC)

Purpose: ICC represents 10-15 % of all malignant hepatic neoplasms. Tumours infiltrating confluence of hepatic veins and IVC are often considered inoperable, especially in elderly patients, since maintainance or reconstruction of venous outflow would require ante situm resection or total vascular exclusion (TVE). Methods: We present the case of a 75 yo woman with history of pulmonary embolism in chronic oral anticoagulant treatment, incidentally diagnosticated with a hepatic mass infiltrating the confluence of hepatic veins and IVC. An extended left trisegmentectomy was performed, with ligation of the three main hepatic veins and IVC resection. Venous outflow of the remnant was guaranteed by preservation of the right inferior hepatic vein (RIHV). Results: Two units of packed red blood cells were transfused. Post operative course was complicated with grade A liver failure. Patient was discharged in 8 pod with normal liver function tests. Diagnosis of biliary type adenocarcinoma pT2N0M0 G2 was made after histological examination. Conclusion: RIHV draining the posteroinferior area of the right liver is described in 17-20 % of population. In 1987, Makuuchi proposed theoretically four types of hepatectomy with resection of the main right hepatic vein (RHV) and preservation of the RIHV. In 1991, Blumgart performed first the procedure, calling this new operation subtotal hepatectomy. Only 9 cases have been described in literature ever since. In 3 of these cases the IVC was also infiltrated. In 3 cases, the surgical procedure was preceded by left portal vein and/or RHV embolization to obtain liver remnant hypertrophy. In 2 cases the operation was performed in 2 steps (ALLPS). In our case, we combined the anterior approach with a modified Hanging Manouver to suspend and resect the liver cranially to the RIHV outlet, then proceeding with ligation of the three main hepatic veins and IVC resection on a tangential clamping. In this way it was possible to perform surgery without total vascular exclusion (TVE). This approach was well tolerated hemodynamically and more feasible than ante situm resection or TVE. Critical aspects remain the section line irregularity and the hepatic congestion due to the venous outflow block which causes more venous bleeding during the parenchymal transection. Another aspect of the procedure is the evaluation of the liver remnant congestion, which in our case was excluded by a clamp test of the posterior hepatic artery and of the RHV stump.

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.

Laparoscopic right hepatectomy and distal MHV resection after portal vein embolization for intraductal papillary neoplasm of bile duct

Summary Objectives: Laparoscopic right hepatectomy is technically demanding procedure particularly for liver tumor. The report of this procedure for cholangiocarcinoma is limited. Besides, following portal vein embolisation (PVE), parenchymal transection is more difficult because of shifting of parenchymal transection plane from atrophy-hypertrophy phenomenon of PVE. And also PVE may induced inflammation around right portal pedicle making individual inflow vascular control is more challenging. We present the case of pure laparoscopic right hepatectomy and distal MHV resection using individual inflow vascular control for patient with intraductal papillary neoplasm of bile duct that involved distal MHV. Preoperatively, the patient underwent portal vein embolization. Methods: After careful searching for intra- and extra-hepatic metastases, cholecystectomy was performed to facilitate right portal pedicle exposure. Individual dissection and ligation of right portal vein, right anterior hepatic artery and right posterior hepatic artery were performed sequentially. Limited liver mobilization was performed to facilitate parenchymal transection. Ultrasonic device and Cavitron Ultrasonic Surgical Aspirator were used for parenchymal transection. Intraoperative ultrasonography was used for identify the point that MHV will be transected. Right hepatic duct was encircled and then divided and sutured. After completed parenchymal transection, right hepatic vein was divided by using stapling devices. Right lobe liver was mobilized completely and placed in plastic bag and removed through Pfannelstiel incision. Results: Pure laparoscopic right hepatectomy was performed successfully without intra-operative complications or blood transfusion. Operative time was 360 minutes and estimated blood loss was 150 ml. Pathology revealed moderately differentiated-intrahepatic cholangiocarcinoma, papillary type, uninvolved all resection margins. Patient was discharged on postoperative day 6 without peri-operative complications. Conclusions: Pure laparoscopic right hepatectomy using individual inflow vascular control is feasible procedure for intraductal papillary neoplasm of bile duct following PVE.

Living donor liver transplantation using left trisection graft with caudate lobe

Summary Background: Due to small remnant volume or anatomical variation, a right liver graft may be precluded in adult living donor liver transplantation (LDLT). Right posterior section, right anterior section graft, or dual donor grafts have been proposed as alternative grafts of right and left liver grafts. Here, we report a case of LDLT using left trisection graft with caudate lobe. Methods: The recipient was a 55-years old female with hepatitis B virus associated liver cirrhosis. The donor had a type III portal vein (PV) anomaly. Donor’s right hepatic artery (HA) was extrahepatically divided into right anterior and posterior HA and left HA was originated from left gastric artery. Preoperative cholangiography showed trifurcation of bile duct. Left trisection graft with caudate lobe was measured 620 gram that was 0.88% of graft to recipient weight ratio. Results: With J shaped incision, hilar dissection of the donor was performed to isolate the left and right anterior and posterior branches of the HA and PV. Then, the liver was transected in a plane that was demarcated on the liver surface, temporarily occluding the right posterior branch of the HA and PV. We encountered 1 PV opening, 1 hepatic vein opening, 3 HAs, and 3 bile duct openings in the left trisection graft with caudate lobe that were safely anastomosed in the recipient. There was no complication in donor and recipient side after operation. Conclusions: Although it was a complex operation, left trisection graft with caudate lobe might be a feasible option for special situations involving donors unsuitable for right liver donation.

Atherosclerosis of the right posterior hepatic artery in a patient with hilar cholangiocarcinoma undergoing left trisectionectomy: a case report of a therapeutic pitfall

BackgroundWe experienced a rare case of benign arterial stricture of the right posterior hepatic artery (RPHA) caused by atherosclerosis in a patient with hilar cholangiocarcinoma.Case presentationA 75-year-old man was referred to our hospital for the detailed investigation of serum hepatobiliary enzyme elevation. The patient had a history of hypertension, type 2 diabetes mellitus, and an operative history of coronary artery bypass grafting 10 years before. Endoscopic retrograde cholangiography found strictures of the right and left hepatic ducts with involvement of right anterior and posterior bile ducts. Adenocarcinoma was evident by brush cytology. We diagnosed these findings as hilar cholangiocarcinoma and planned left trisectionectomy including bile duct reconstruction. Although the tumor and RPHA were not adjacent, preoperative multidetector computed tomography revealed a stricture of the RPHA that was 5.6 mm in length. We suspected that atherosclerosis caused the stricture, and we performed digital subtraction angiography and intravascular ultrasonography that showed stricture of the RPHA accompanied by thick plaques in the arterial wall. We placed a bare-metal stent in the RPHA and then performed left trisectionectomy. Since this patient developed bile leakage postoperatively, percutaneous drainage was performed. The bile leakage was successfully controlled, and the patient was discharged 3 months after surgery. Unfortunately, 4 months after hepatectomy, he was re-hospitalized with multiple pyogenic liver abscesses. We performed intensive multimodal treatment for the liver abscesses and stabilized the disease; however, we eventually lost this patient due to liver failure 14 months after surgery.ConclusionTo the best of our knowledge, there is no previous literature on atherosclerosis of the RPHA, which was evident preoperatively in our case. Because arterial complications may lead to critical biliary complications in patients who undergo left trisectionectomy, we first performed prophylactic arterial stent placement. We speculate that existing chronic microscopic injury of the peribiliary plexus might have caused the liver abscesses. We successfully diagnosed atherosclerosis of the RPHA preoperatively. However, further investigation of patients is warranted to determine if left trisectionectomy is contraindicated in these patients.

Laparoscopic extended posterior sectorectomy for metastatic adrenocortical carcinoma: a minimally invasive approach to parenchymal preservation

Background: Parenchymal preservation contributes to improved morbidity and mortality after hepatic resection. Additionally, randomized data supports minimally invasive (MIS) approaches to hepatic resection, resulting in shortened hospitalization, reduced postoperative morbidity, and improved quality of life. The Wakabayashi complexity index for laparoscopic hepatectomy guides patient selection, but the combination of MIS and parenchymal preservation for complex hepatic resections is seldom performed. Methods: A 65-year old male with adrenocortical carcinoma was treated with a laparoscopic left adrenalectomy in 2012. Surveillance MRI 5 years later identified a new 1.7 cm lesion located adjacent to the right hepatic vein in segment 7 (Figure). Percutaneous biopsy was consistent with metastatic adrenocortical carcinoma. Given the prolonged disease-free interval, extended right posterior sectorectomy was recommended. Results: The patient was placed in a split leg French position. A 3-D laparoscope was used and 4 port sites were required. Taking advantage of patient anatomy, the right posterior hepatic artery and portal vein were ligated and divided within the porta hepatis. The translation of open parenchymal transection techniques with crush-clamping, energy, and staplers facilitated safe laparoscopic dissection between the anterior and posterior sectors, with control of intrahepatic vascular structures and ultimate division of the right hepatic vein at its origin. Conclusion: Parenchymal preservation leveraging MIS technique facilitated complete resection of an isolated adrenocortical carcinoma metastasis. Laparoscopic extended posterior sectorectomy allowed for rapid progression through postoperative milestones with early discharge and salvage of the majority of the anterior sector, thereby reducing this patient’s risk for postoperative liver failure and mortality.

The Pitfalls of Left Trisectionectomy or Central Bisectionectomy for Biliary Cancer: Anatomical Classification Based on the Ventral Branches of Segment VI Portal Vein Relative to the Right Hepatic Vein

BackgroundsSome patients have P6a running on the ventral side (Ventral-P6a), relative to the right hepatic vein (RHV). Study DesignForty-one patients who underwent left trisectionectomy or central bisectionectomy for biliary cancer were enrolled. We compared the anatomical features using 3D images and surgical outcomes between patients with Ventral-P6a (n = 17) and those with P6a running on the dorsal side relative to the RHV (Dorsal-P6a; n = 25). Moreover, the liver volume by hand-tracing 2D axial images was compared to the volume calculated using the 3D images. ResultsThe frequency of complete exposure of RHV on the transection plane was less in Ventral-P6a (12 vs. 76%; p < 0.001), and the frequency of supraportal type of right posterior hepatic artery (RPHA, 29 vs. 4%, p = 0.020), the presence of inferior RHV (47 vs. 12%, p = 0.011), and the angle between the transection plane of segment VI and VII (S6–S7angle, 29.0° vs. 4.9°; p < 0.001) were greater in Ventral-P6a than in Dorsal-P6a. In Dorsal-P6a, the volume of posterior section calculated using 2D images was greater than that calculated using 3D images (404 vs. 370 mL; p = 0.004). The incidence of daily diuretic administration in Dorsal-P6a was greater than in Ventral-P6a (88 vs. 54%, p = 0.035). Conclusion and RelevanceIn Ventral-P6a, the complete exposure of RHV was rare in left trisectionectomy or central bisectionectomy. Surgeons should preoperatively recognize the course of RPHA, the presence of inferior RHV, and the S6–S7angle. In Dorsal-P6a, the volume of posterior section, which tended to be overestimated using 2D images, was smaller than that in Ventral-P6a.

Doppler Characteristics of Recurrent Hepatic Artery Stenosis.

We sought to assess midterm sonographic findings in patients after stenting for hepatic artery stenosis. Thirty-nine hepatic artery stent procedures were performed for hepatic artery stenosis after liver transplantation between September 2009 and December 2013. Thirty cases were technically successful and met the minimum follow-up time (76 days, defined by earliest diagnosed stenosis). Routine ultrasound surveillance was obtained on all patients, and statistical analysis of the findings in the patency and restenosis groups was performed. Of the 30 cases, restenosis occurred 9 times in 6 patients. Mean follow-up was 677 days. Mean time to restenosis was 267 days. Five cases (56%) were identified within the first 6 months after stent placement. Four cases (44%) were recognized in the second year after stent placement. Prior to the sonographic diagnosis of restenosis, the mean resistive indices of the main (.64 versus .57, P < .0001), left (.63 versus .54, P < .0001), right anterior (.60 versus .52, P < .0001), and right posterior (.60 versus .53, P = .001) hepatic artery branches differed among patency and restenosis groups, respectively. The mean peak systolic velocity also differed significantly between the 2 groups: 254 cm/sec in patients with eventual restenosis versus 220 cm/sec in patients without restenosis (P = .02). The sonographic evaluation of hepatic artery stenosis remains critical during the first 2 years after stent placement. While the vast majority of patients do not restenose, resistive index and peak systolic velocity differed significantly between the 2 groups and may be prognostic surveillance markers for the development of restenosis.

Anatomic features of independent right posterior portal vein variants: Implications for left hepatic trisectionectomy

No authors have reported on the anatomic features of the independent right posterior portal vein variant and its relevance to left hepatic trisectionectomy. The purpose of this study was to review vasculobiliary systems according to portal vein anatomy, to clarify the anatomic features of the right posterior portal vein variant, and to discuss its operative implications for left hepatic trisectionectomy. In a radiologic study, the 3-dimensional anatomy of the portal vein, hepatic artery, and bile duct were studied in 200 patients who underwent computed tomography. In a surgical study, medical records were retrospectively reviewed for 463 patients who underwent hepatectomy for perihilar cholangiocarcinoma. In the radiologic study, an independent right posterior portal vein variant was observed in 19 patients. The following observations were made in association with the portal vein variant: (1) a supraportal or combined type right posterior hepatic artery was never found; (2) an infraportal right posterior bile duct was observed at a significantly greater frequency than in patients with normal portal vein anatomy; and (3) the volume of the right posterior sector was significantly larger than in normal portal vein anatomy (37.4 ±6.1% vs 27.3 ±5.1%, P<.001). In the surgical study, the independent right posterior portal vein variant was observed in 41 (8.9%) patients. Of the 135 patients who underwent left hepatic trisectionectomy, 28 (20.7%) had this portal vein variant. Independent right posterior portal vein variants exhibit anatomic features that are advantageous for performing left hepatic trisectionectomy.

Surgical anatomy of the right hepatic artery in Rouviere's sulcus evaluated by preoperative multidetector-row CT images.

BackgroundLymph node dissection in Rouviere’s sulcus (RS) is essential during left-sided hepatectomy and caudate lobectomy for hilar cholangiocarcinoma. However, the small segmental or subsegmental arteries (SA/SSA) are often encountered in RS and must be preserved to prevent critical complications, such as liver infarction or liver failure. The aim of this study is to elucidate the anatomy of SA/SSA around RS, which should be understood preoperatively.MethodsBetween January 2008 and April 2013 from a total of 124 consecutive patients with hilar cholangiocarcinoma, preoperative multidetector-row computed tomography (MDCT) images were obtained at our institution and evaluated. The bifurcation patterns of the SA/SSA, the courses of the posterior SA/SSA and the bifurcation site of the SA/SSA were investigated using MDCT images.ResultsThe typical form, in which right hepatic artery (RHA) bifurcated into the anterior (Aant) and posterior (Apost) hepatic artery and thereafter, Aant/Apost bifurcated into the SA and SSA, was observed in 75 patients (60.5 %). On the other hand, the atypical forms, in which the SA/SSA were independently branched off from RHA before the main bifurcation of the Aant and Apost, were observed in 43 patients (34.7 %). The prior branched arteries supplied the whole or ventral area of segment VI (A6 or A6a) in 11 patients (8.9 %), which was most commonly observed in the atypical form. 15 patients (34.9 %) of the 43 patients with atypical form had partially supraportal posterior branches, that showed early-bifurcated posterior SA/SAA following supraportal course, while the other posterior SA/SSA followed infraportal course. The SA/SSA were extrahepatically bifurcated in 82 patients (66.1 %), comprised of all 43 atypical form and 39 of typical form, while the SA/SSA were intrahepatically bifurcated in remaining 36 patients of typical forms (29.0 %).ConclusionThe extrahepatic bifurcation of the SA/SSA from RHA was relatively common. The early-bifurcated SA/SSA was often observed (34.7 % of total cohort) and, in 34.8 % of those atypical forms, posterior SA/SSA from RHA followed a supraportal course. The detailed preoperative knowledge of the anatomy, including SA/SSA, is crucial for left-sided hepatectomy for hilar cholangiocarcinoma.

In Vivo Evaluation of Feeding Arteries of Tumors in Dorsal Sector of the Liver.

Background:The identification of the dorsal sector of the liver and its detailed vascular anatomy is of primary importance for surgical practice and segmental transcatheter arterial chemoembolization.Objectives:This study aimed to investigate the feeding arteries of tumors in dorsal sector of the liver.Patients and Methods:Computed tomography (CT) and digital subtraction angiography (DSA) images of eleven patients with tumors of the dorsal sector of the liver were analyzed retrospectively. The hepatic arteries that probably supplied the tumors were observed in DSA images. The case number of each hepatic artery feeding to the tumors was calculated. A scoring method was used to estimate each hepatic artery contribution to the tumor stain in DSA images. The accumulative scores were employed to evaluate the blood supply of feeding arteries of the tumors.Results:The data of the study revealed that right posterior hepatic artery (RPHA) (n = 9), middle hepatic artery (MHA) (n = 8), left medial hepatic artery (LMHA) (n = 6), right anterior hepatic artery (RAHA) (n = 5), and caudate hepatic artery (CaHA) (n = 3) were the feeding arteries of the tumors in dorsal sector in eleven patients. The accumulative scores of RPHA, MHA, RAHA, and LMHA were 23, 17, 11, and 7 points, respectively (χ2 = 6.827, P = 0.078, Friedman test). The total scores of right hepatic artery (RHA) branches and left hepatic artery (LHA) branches were 51 and 11 points, respectively (Z = -2.764, P = 0.006, Wilcoxon rank test).Conclusion:The RPHA, MHA, RAHA, and LMHA might be the main feeding arteries of the tumors in dorsal sector of the liver.

A successful case of pancreaticoduodenectomy with resection of the hepatic arteries preserving a single aberrant hepatic artery for a pancreatic neuroendocrine tumor: report of a case

A 65-year-old male with a pancreatic neuroendocrine tumor presenting with a duodenal ulcer was referred to our department. The tumor involved the common hepatic artery, gastroduodenal artery, left hepatic artery and the right posterior hepatic artery, but not the right anterior hepatic artery originating from the superior mesenteric artery. The hepatic arteries, except the aberrant right anterior hepatic artery, were embolized using coils 18 days before the surgery. The patient underwent pancreaticoduodenectomy with resection of the tumor-encased hepatic arteries, while preserving the aberrant artery. The patient was discharged uneventfully on postoperative day 13 with no ischemic complications. A histopathological examination revealed a grade 2 pancreatic neuroendocrine tumor according to the classification of the World Health Organization, and the surgical margin was negative. The patient developed hepatic metastases 16 months after surgery; hence, hepatic resection was performed. The present surgical strategy is applicable in patients with relatively low-grade pancreatic malignancies involving major hepatic arteries.

Pitfall of Right Lateral Sector Graft Procurement

Selection of a right lateral sector graft for adult-to-adult living donor liver transplantation (LDLT) has become feasible (1, 2). Herein, a case of right lateral sector graft procurement for liver transplantation is presented in which technical difficulties were encountered because of an anomaly of the right posterior hepatic artery. A 21-year-old male patient volunteered to serve as a live donor for liver transplantation for his brother who was suffering from fulminant hepatitis. A volumetric analysis revealed that only a right lateral sector graft would be suitable (3). Preoperative computed tomography revealed a supraportal right posterior hepatic artery, i.e., the right posterior hepatic artery running cranially over the right anterior portal vein (Fig. 1A, B), and the vascular anomaly was confirmed intraoperatively (Fig. 1C). Isolation of the right posterior hepatic artery was difficult during procurement of the graft because it ran between the right posterior portal vein and the posterior bile duct. Furthermore, the distal part of the right posterior hepatic artery was very thin, and the dissection between the perivascular tissue and the distal part of the right posterior hepatic artery was technically difficult, and had risk of injury by approach from the hepatic hilum.FIGURE 1: A, computed tomographic image showing the right posterior hepatic artery running cranially over the right anterior portal vein, i.e., supraportal right posterior hepatic artery (arrowhead). B, the three-dimensional reconstruction image of the computed tomography. The view is from the caudal side of the patient similar to the intraoperative view. The arrowhead indicates the supraportal right posterior hepatic artery. C, the intraoperative findings confirmed the preoperative imaging findings. The arrowhead indicates the supraportal right posterior hepatic artery. RHA, right hepatic artery; RAHA, right anterior hepatic artery; RPHA, right posterior hepatic artery; RPV, right portal vein; RAPV, right anterior portal vein; RPPV, right posterior portal vein.Therefore, after hilar dissection, the hepatic parenchymal transection was completed. At this stage, the right lateral sector was connected only via the posterior portal pedicle and the right hepatic vein. Under intraoperative cholangiography, the posterior duct was carefully divided. Probably because the dissection between the perivascular tissue and the distal part of the right posterior hepatic artery was insufficient, during division of the posterior duct, the distal part of the right posterior hepatic artery was injured. The right hepatic artery was temporarily clamped and the right lateral sector graft was procured by dividing the right posterior hepatic artery, the posterior portal vein, and the right hepatic vein, in that order. The right posterior hepatic artery was divided at the peripheral side after it had crossed the right anterior portal vein. Implantation of the right lateral sector graft was successfully carried out. The only problem was that the blood flow of the initial end-to-end anastomosis between the recipient hepatic artery and donor right posterior hepatic artery was insufficient. Therefore, a re-anastomosis was performed after trimming the anastomosis line and finally sufficient blood flow was obtained. The postoperative course was uneventful in both the donor and the recipient. Five hundred eleven LDLTs were performed at the institution between January 1996 and August 2013. During this period, a right lateral sector graft was procured in 27 cases (5.3%). The case presented herein was the only one with this type of vascular anomaly. Yoshioka et al. have reported encountering this type of anomaly during extended left hepatectomy for cholangiocarcinoma (4). The reported incidence of supraportal right posterior hepatic artery is 5.4%. The reported incidence of infraportal hepatic artery for segment 6 and supraportal hepatic artery for segment 7, i.e., the combined type of anomaly, is 6.4%. Because the right anterior portal vein cannot be cut during a donor operation, the difficulty posed by this anomaly is even greater during right lateral sector graft procurement than during surgery for cholangiocarcinoma. In cases with the combined type of anomaly, reconstruction of the right posterior hepatic artery is necessary. This case underscores the importance of paying attention to the course of the right posterior hepatic artery during right lateral sector graft procurement. Because supraportal right posterior hepatic artery can cause accidental arterial injury, complete transection before cutting of the posterior portal pedicle is recommended. Takashi Kokudo 1 Kiyoshi Hasegawa1 Yasuhiko Sugawara1 Norihiro Kokudo1,2 1Hepato-Biliary-Pancreatic Surgery Division and Artificial Organ and Transplantation Division Department of Surgery Graduate School of Medicine The University of Tokyo Tokyo, Japan

Delayed, life-threatening hemorrhage after self-expandable metallic biliary stent placement: clinical manifestations and endovascular treatment

Life-threatening, delayed hemorrhage after self-expandable metallic stent (SEMS) insertion for malignant biliary obstruction is very rare. Clinical manifestations, radiologic characteristics, treatment, and prognosis of this complication are not well-known. To present the clinical manifestations, radiologic findings, and endovascular treatment of life-threatening, delayed hemorrhage secondary to SEMS placement. A total of six patients (five men and one woman; mean age, 65.5 years) with life-threatening, delayed arterial bleeding after SEMS placement for malignant bile duct obstruction were recruited between 2000 and 2011 from three different hospitals in Korea. The original SEMS placement in all patients utilized either percutaneous (n = 3) or endoscopic approaches (n = 3). We retrospectively reviewed the clinical presentations, computed tomography (CT) and angiographic findings, endovascular treatments, and prognoses of these patients. All patients presented with life-threatening gastrointestinal bleeding such as melena (n = 4), hematochezia (n = 1), and hematemesis (n = 1). Mean time period between biliary metallic stent insertion and presentation with bleeding was 75 days (range, 15-152 days). All stents were encased by primary or metastatic cancer along with nearby arteries on CT images. Digital subtraction angiogram (DSA) revealed pseudoaneurysm close to the stent (n = 2), in-stent pseudoaneurysm (n = 2), arteriobiliary fistula (n = 1), or pseudoaneurysm with arteriobiliary fistula (n = 1). The origins of hemorrhage were the gastroduodenal artery (n = 3), the aberrant right posterior hepatic artery from the gastroduodenal artery (n = 2), and the right hepatic artery (n = 1). Hemorrhages were successfully controlled after intra-arterial coil embolization in five patients followed by placement of a stent graft and direct puncture N-butyl-2-cyanoacrylate (NBCA) embolization in one patient. Life-threatening, delayed hemorrhage within a metallic biliary stent may occur if a stent is placed across the bulky bile duct tumor or tumor encases the stent. Bleeding can be successfully treated with endovascular treatment. However, the overall prognosis was poor.

A Case of Ruptured Mycotic Hepatic Artery Aneurysm Successfully Treated Using Arterial Embolization

Mycotic hepatic artery aneurysms (HAAs) have become very rare due to antibiotics. Untreated, they have a high possibility of rupture and mortality. In this paper, on the case of a 67-year-old male who had severe right-upperquadrant abdominal pain and a history of infective endocarditis is reported. The computed tomography (CT) and arterial angiography findings led to a diagnosis of a ruptured mycotic HAA. The CT showed an HAA and the formation of an intrahepatic hematoma caused by aneurysmal rupture. The arterial angiography showed a mycotic HAA that arose from the right posterior hepatic artery. Percutaneous transcatheter arterial embolization was used to successfully treat the HAA. Since then, the patient has been doing well, without symptoms.

“Supraportal” Right Posterior Hepatic Artery: An Anatomic Trap in Hepatobiliary and Transplant Surgery

A supraportal right posterior hepatic artery (RPHA), which runs cranially to the right portal vein and goes to the liver, has never been described. The course of the RPHA to the right portal vein was evaluated, using (1) computed tomography (CT) arteriography and portography in 300 patients who underwent multidetector row CT (radiologic study) and (2) operative records in 203 patients who underwent left-sided hepatectomy for perihilar cholangiocarcinoma (surgical study). In the radiologic study, an infraportal type RPHA was observed in 239 (79.7%) patients, a supraportal type in 35 (11.7%), and a combined type in 26 (8.7%). In the surgical study, an infraportal type was observed in 179 (88.2%) patients, a supraportal type in 11 (5.4%), and a combined type in 13 (6.4%). In two patients with the combined type RPHA, the supraportal hepatic artery of the right posterior superior segment (A7) was injured during surgery. In another two patients with advanced carcinoma involving the supraportal PRHA, combined hepatic artery resection and reconstruction was necessary. Overall, in 4 (17.4%) of the 24 hepatectomized patients with supraportal or combined type RPHA, iatrogenic injury during surgery or cancer invasion of the hepatic artery occurred due to the course of the RPHA itself. In contrast, 179 hepatectomized patients with infraportal type RPHA did not have such course-dependent complications. The supraportal RPHA runs just beneath the right hepatic duct, which may function as an anatomic trap during hepatobiliary and transplant surgery.

Three-dimensional C-arm Cone-beam CT: Applications in the Interventional Suite

C-arm cone-beam computed tomography (CT) with a flat-panel detector represents the next generation of imaging technology available in the interventional radiology suite and is predicted to be the platform for many of the three-dimensional (3D) roadmapping and navigational tools that will emerge in parallel with its integration. The combination of current and unappreciated capabilities may be the foundation on which improvements in both safety and effectiveness of complex vascular and nonvascular interventional procedures become possible. These improvements include multiplanar soft tissue imaging, enhanced pretreatment target lesion roadmapping and guidance, and the ability for immediate multiplanar posttreatment assessment. These key features alone may translate to a reduction in the use of iodinated contrast media, a decrease in the radiation dose to the patient and operator, and an increase in the therapeutic index (increase in safety-vs-benefit ratio). In routine practice, imaging information obtained with C-arm cone-beam CT provides a subjective level of confidence factor to the operator that has not yet been thoroughly quantified.

Establishment of a Guideline for the Safe Management of Anatomical Hepatic Artery Variations While Performing Major Hepato-pancreatico-biliary Surgery

Purpose: Hepato-pancreatico-biliary (HPB) surgeons often must make decisions regarding hepatic artery (HA) resection while performing major HPB surgery. The purpose of this report was to review and summarize HA resection experience with a focus on vascular preservation during major HPB surgery and to develop a useful algorithm in dealing with these needs. Methods: We reviewed 1,324 cases that had available computed tomographic and angiographic findings and summarized the problematic HA variations encountered in major HPB surgery. In reviewing our series and previous studies, we have created a set of guidelines that enables a pragmatic approach to the unique variations in HA and the risks of cancer invasion. Results: Challenging HA variations during major HPB surgery were found in 25.7% of the cases and included variations of common HA from superior mesenteric artery (SMA), gastroduodenal artery (GDA), aorta, celiaco-mesenteric (CM) trunk or left gastric artery (LGA) (3.70%), the variations of the right HA from SMA, GDA, aorta, celiac axis (CA) including CM trunk or LGA (12.76%), the variations of the left HA from LGA, CA or GDA (4.46%), and the mixed types of the aberrant left medial HA and/or left lateral HA and/or right anterior HA and/or right posterior HA (2.11%). Conclusion: Surgeons should have knowledge of the anatomically variable vasculature of the HA when planning for major HPB surgery. Preoperative imaging studies can aid and should be performed in anticipation of potential HA variations during major HPB surgery.