Normal Hepatic Artery Research Articles

ACCESSORY RIGHT HEPATIC ARTERY AS PRINCIPAL, ARISING FROM PROPER HEPATIC ARTERY /CASE REPORT/

The good knowledge for the normal hepatic artery distribution and the possible anatomical variations is significant in liver transplantation in order for the vascularity not to be disturbed and to cause necrosis of the liver parenchyma postoperatively. Disruption of an anatomical artery variation is uncommon in liver hilum dissection, but non establishment of continuity in time of reconstruction is an important cause for postoperative complications such as acute liver failure and augment morbidity and mortality. The aim of this case report is to present a non published anatomical variation of accessory right hepatic artery arising from proper hepatic artery between the branching of gastroduodenal artery and bifurcation of the proper hepatic artery to right and left branches.

Doppler Ultrasound Findings in the Hepatic Artery Shortly After Liver Transplantation

The purpose of this article is to describe the Doppler waveform findings in the hepatic artery in the early posttransplantation period, both in the absence and presence of arterial complications. The presence of transient high-resistance Doppler waveforms in normal hepatic arteries is a common finding after grafting. Hepatic artery thrombosis and stenosis, and arterial steal syndromes can be diagnosed by Doppler in the early liver transplantation period.

Accuracy of Multidetector Computed Tomographic Angiography for Detecting Hepatic Artery Complications After Liver Transplantation

Aims The aim of this study was to evaluate the accuracy of multidetector computed tomographic angiography (MDCTA) for detecting hepatic artery complications after liver transplantation. Methods Between July 2001 and September 2006, 212 patients underwent liver transplantation including 110 (41 female and 69 male patients); of mean age, 24 years (range = 6 months to 66 years) who were assessed with MDCTA. First, arterial phase images obtained after intravenous injection of 150 mL of contrast at a rate of 4 mL/s were acquired using the bolus triggering technique. Then portal and late-phase images were obtained. Axial and coronal maximum intensity projection (MIP) images and volume-rendered images were produced from the axial image data. Arterial vascular complications were noted. Stenosis was defined as severe (>75%), moderate (≥50%), or mild (<50%) according to its diameter. Twenty-nine of the 38 individuals with hepatic artery complications detected by MDCTA had correlative digital subtraction angiography (DSA). Seven of 110 patients with normal hepatic artery and venous pathologies in MDCTA also had DSA to investigate venous complications. Results MDCTA showed hepatic artery complications in 38 of the 110 patients who were assessed with this modality. DSA confirmed the MDCTA findings in all but 1 of the 29 patients assessed with catheter angiography. Fourteen of the 38 individuals also underwent percutaneous interventions and treatment. Fifteen patients had early hepatic artery complications, and 23 late hepatic artery complications. The most common early complications were thrombosis (66.6%) and stenosis (26.6%). The most common late complications were stenosis (56.5%) and thrombosis (26%). If we evaluate the early and late complications, the incidence of late complications was greater than that of the early complications (61% vs 39%). There was no statistically significant difference in cadaveric and living donor liver transplants for early versus late or for type of complications. Conclusions MDCTA is noninvasive imaging modality that accurately shows a variety of vascular complications after liver transplantation. We suggest that if we suspect any vascular complication with Doppler ultrasound, we must perform MDCTA for diagnosis. If we detect severe/moderate stenosis, the patient must undergo DSA.

Liver Transplantation From a Donor Affected by Marfan's Syndrome

Marfan's Syndrome (MS) is a systemic inheritable connective tissue (CT) disease related to fibrillin-1 genetic mutation, which gives an abnormal consistency to the CT. This compromised structure of the CT is related to cardiovascular, skeletal, and ocular system complications (1, 2). A 49-year-old patient underwent liver transplantation (LT) for hepatitis C virus-related end-stage liver disease and hepatocellular carcinoma. The donor was a 17-year-old female with MS pronounced brain dead from postanoxic brain injury. Her clinical findings from MS were characterized by severe mitral valve prolapse and bone-joint abnormalities. She was not affected from any vascular manifestation of arterial degeneration; however, the liver was the only organ harvested. Histological hepatic artery analysis, performed over the procurement, appeared normal; therefore, the organ was considered suitable. Before procurement, the recipient received a thorough informed-consent about MS. During posttransplant follow-up, the graft hepatic artery was checked by serial ultrasound-Doppler scans, weekly for the first month and subsequently once per month; angio-computed tomography scan was performed on the sixth month. The vascular changes from MS mostly involve the main vessels (incidence ranged between 30% and 50%) because of the greater content of compromised CT within the vessel walls and to the higher pressure and blood flow the arteries are exposed to. The incidence of visceral artery changes is approximately 0.4−2% and is usually manifested with cystic medionecrosis (1–3). In the literature, only two hepatic artery complications are described in patients with MS. Santiago-Delpin et al. (4) described a case of incomplete MS with multiple aneurysms of the aorta and its branches, in which a hepatic artery aneurysm perforated into the common bile duct. Ruschen et al. (5) in 1984 published a case in which a spontaneous hepatic artery rupture occurred in a patient with MS. The FBN1-gene mutation persists in the transplanted graft and, theoretically, may increase the risk of vascular complications such as dilation, aneurysmal changes, dissection, and intimal tears (6). Our rationale to accept a donor with MS was based on the low incidence of hepatic artery complications and total absence of hepatic dysfunction in patients with MS. The normal hepatic artery biopsy also gave a crucial piece of information in the acceptance process. Farese et al. (6) suggested another potential complication occurring in this setting: the possibility of antibodies developed against mutated fibrillin-1 donor liver cells. To date, we have not detected any posttransplant liver dysfunction and the recipient has not presented graft rejection. In conclusion, LT from MS donors may represent an opportunity to expand the potential donor pool. Moreover, the mean age at death of patients affected from MS is 45 (±16) years old; therefore, the liver status of such a young donor should be better than common marginal donors (7, 8). The biopsy at the time of procurement should be the first step in accepting an organ from a patient with MS. Furthermore, we advocate a closer follow-up of the graft vessels by means of Doppler-ultrasound in patients receiving such a graft. After a follow-up of 10 months our recipient did not show signs of graft complications or hepatic artery changes. Fabrizio Di Benedetto Stefano Di Sandro Nicola De Ruvo Michele Masetti Liver and Multivisceral Transplant Center University of Modena and Reggio Emilia Modena, Italy Cristiano Quintini Department of General Surgery Cleveland Clinic Foundation Cleveland, OH Roberto Montalti Roberto Ballarin Giorgio E. Gerunda Liver and Multivisceral Transplant Center University of Modena and Reggio Emilia Modena, Italy

Imaging of Multistep Human Hepatocarcinogenesis by CT during Intra-Arterial Contrast Injection

Various types of hepatocellular nodules are seen in cirrhotic livers. In these nodules, two types of human hepatocarcinogenesis are now considered. One is de novo hepatocarcinogenesis and the other is the stepwise development from high-grade dysplastic nodule (DN), high-grade DN with well-differentiated HCC foci, and overt HCC. According to our analysis by CT during arterial portography (CTAP) and CT during hepatic arteriography (CTHA) and histological study, in accordance with the elevation of the grade of malignancy of the nodules, the portal tract including normal portal vein (intranodular portal supply) and hepatic artery (intranodular arterial supply through normal hepatic arteries) are decreased. On the other hand, abnormal artery (intranodular arterial supply through newly formed abnormal arteries) gradually increases. Therefore, we can estimate the grade of malignacy of the nodules from intranodular blood supply. To know this blood supply pattern is important for the early detection, characterization and treatment of early stage HCCs. We also revealed that there was a close correlation between the prognosis of the nodules and the blood supply patterns.

Advantage in using living donors with aberrant hepatic artery for partial liver graft arterialization.

In living-related partial liver transplantation, the feasibility and safety of using left-sided liver grafts from donors with aberrant hepatic arteries remains to be evaluated. Between 1996 and 2000, we harvested left-sided liver grafts from 101 living donors. Hepatic arterial variation in the donors was classified into three types: type I (n=69), normal anatomy; type II (n=24), aberrant left hepatic artery arising from the left gastric artery; and type III (n=8), replaced right hepatic artery arising from the superior mesenteric artery. We performed arterial reconstructions using the donor's left hepatic artery in 70 cases (69 in type I, 1 in type II), an aberrant left hepatic artery in 24 cases (23 in type II, 1 in type III), and the common hepatic artery in 7 cases (all in type III). The diameter and length of the anastomosed hepatic artery were larger (2.5+/-0.7 vs. 2.0+/-0.8 mm, P=0.03) and longer (42.0+/-14.7 vs. 9.0+/-7.3 mm, P<0.0001) in cases in which the aberrant left hepatic artery or common hepatic artery was used for the anastomosis (n=31) than in those using the left hepatic artery (n=70). Hepatic arterial occlusion occurred in nine patients, with the incidence of occlusion tending to be lower in the former cases in which aberrant left or common hepatic arteries were used (3.2% vs. 11.4% for the left hepatic artery group, P=0.15). Because thicker and longer arterial branches can be obtained in left-sided liver grafts with aberrant hepatic arteries than in grafts with normal left hepatic arteries, their use is advantageous for safe arterialization in partial liver grafts.

The value of portal vein pulsatility on duplex sonograms as a sign of portal hypertension in children with liver disease.

The purpose of this study was to determine the significance of portal vein pulsatility on duplex Doppler waveforms in children with end-stage hepatic failure undergoing liver transplantation. Thirty-eight children with end-stage hepatic decompensation were examined with color-assisted spectral Doppler waveform analysis of the hepatic artery and the portal vein. Correlation was made with age, duration of illness, clinical and pathologic diagnosis, and presence of portal hypertension. Findings were compared with those for six patients with acute viral hepatitis and 12 healthy control subjects. Portal vein pulsatility was noted in all 36 patients in whom portal vein flow was detected by Doppler imaging. The majority of these (34) had clinical or sonographic evidence of portal hypertension. In two patients, no portal vein flow was identified in the liver hilum; both had a large portosystemic shunt through collaterals or surgical graft. Significantly increased pulsatility of the hepatic artery waveform (resistive index [RI] = 0.89 +/- 0.15, p < .0001) was seen in patients with end-stage liver disease. In contrast, no portal vein pulsatility and normal hepatic artery pulsatility (RI = 0.60 +/- 0.11) was noted in all patients with acute hepatitis and control subjects. Portal vein waveform pulsatility is 94% sensitive and 90% specific for portal hypertension in end-stage liver disease.

Doppler velocity histogram analysis of hepatocellular carcinoma.

To study the characteristics of tumor blood flow, flow profiles from hepatocellular carcinomas (39 profiles) and normal hepatic arteries (23 profiles) were evaluated using velocity histograms obtained with Doppler ultrasound. The histograms were classified into three types: (1) high-peak, (2) flat, and (3) low-peak. Characteristically, the low-peak types and the flat types, with flows in opposing directions, were seen only in the tumor vessels. The turbulence in a phantom flow model was of the low-peak type. Spectral analysis revealed that the velocity profile of tumor blood flow was different from that of noncancerous flow and that tumor blood flow was characterized by turbulence.

Doppler ultrasound as a screen for hepatic artery thrombosis after liver transplantation.

Doppler ultrasound as a screen for hepatic artery thrombosis after liver transplantation.

Sonographic anatomy of the hepatic artery.

One hundred clinical abdominal sonographic examinations were assessed to determine the frequency with which various parts of the hepatic artery system were imaged. The common, proper, and right hepatic arteries were seen in a large percentage of cases (92%, 75%, and 73%, respectively). Sixty-one consecutive patients with dilated biliary ducts were evaluated to determine the relationship of hepatic artery branches to the biliary tree and portal venous system. Normal and variant hepatic artery anatomy is discussed. Knowledge of the hepatic artery system and its variations is useful in the sonographic assessment of problems involving the gallbladder, liver, pancreas, and portal venous system.

Computed tomography and angiography of cavernous hemangiomas of the liver.

Cavernous hemangioma is the most common benign tumor of the liver. Eighteen patients were studied by both computed tomography (CT) and angiography. The angiographic features were classic, consisting of normal hepatic arteries, no tumor vessels, and densely stained blood-filled spaces producing a "cotton-wool" appearance. Before contrast infusion, CT scans showed roughly spherical, well-demarcated low-density masses; afterward there was a peripheral zone of enhancement which varied in thickness and sometimes had a corrugated inner margin, though the center remained low in density and the overall size of the lesion did not change. The authors feel that the CT findings are characteristic and that in some cases angiography is unnecessary.