Hepatic Arterial Flow Research Articles

Gastroduodenal artery disconnection during liver transplantation decreases non-anastomotic stricture incidence

BackgroundThe hepatic artery is the only blood source nourishing the biliary duct and associated with biliary complication after liver transplantation (LT). Gastroduodenal artery (GDA) disconnection increased proper hepatic artery flow. Whether this procedure attenuates biliary non-anastomotic stricture (NAS) is not clear. MethodsA total of 241 patients with LT were retrospectively analyzed. The patients were divided into the GDA disconnection (GDA-) and GDA preservation (GDA+) groups. Propensity score matching (PSM) was administrated to reduce bias. Logistic regression was conducted to analyze risk factors for biliary NAS before and after PSM. Postoperative complications were compared. Kaplan-Meier survival analysis and log-rank tests were performed to compare overall survival. ResultsIn all, 99 patients (41.1%) underwent GDA disconnection, and 49 (20.3%) developed NAS. Multivariate logistic regression revealed that GDA preservation (OR = 2.24, 95% CI: 1.11-4.53; P = 0.025) and model for end-stage liver disease (MELD) score > 15 (OR = 2.14, 95% CI: 1.12-4.11; P = 0.022) were risk factors for biliary NAS. PSM provided 66 pairs using 1:2 matching method, including 66 GDA disconnection and 99 GDA preservation patients. Multivariate logistic regression after PSM also showed that GDA preservation (OR = 3.15, 95% CI: 1.26-7.89; P = 0.014) and MELD score > 15 (OR = 2.41, 95% CI: 1.08-5.36; P = 0.031) were risk factors for NAS. When comparing complications between the two groups, GDA preservation was associated with a higher incidence of biliary NAS before and after PSM (P = 0.031 and 0.017, respectively). In contrast, other complications including early allograft dysfunction (P = 0.620), small-for-size graft syndrome (P = 0.441), abdominal hemorrhage (P = 1.000), major complications (Clavien-Dindo grade ≥ 3, P = 0.318), and overall survival (P = 0.088) were not significantly different between the two groups. ConclusionsGDA disconnection during LT ameliorates biliary NAS incidence and may be recommended for application in clinical practice.

Assessment of liver blood flow regulation mechanism by ultrasound

The constancy of hepatic blood flow is important for several homeostatic roles. This paper reviews studies related to liver blood flow regulation mechanism. The liver has mechanism maintain a constant hepatic blood flow and compensate for portal flow changes. A reduction in portal flow leads to reduced intrahepatic distending pressure, resulting the hepatic arterial buffer response causes dilation of the hepatic artery, thus buffering the Portal flow change. This mechanism is exclusive to this specific vascular bed and offer a great illustration of multiple integrative regulation of a significant homeostatic organ. Ultrasound provides noninvasive accurate information on the liver hemodynamic and assess the flow in the hepatic artery and the portal vein specially diameter of vessels. Aim: The aim of this study was to evaluate the dual hepatic blood supply in normal individual and compared altered in the hepatic artery buffer response with chronic hepatic diseases. Materials and methods: The current review focuses on researches that evaluate the mechanisms involved in maintaining a steady hepatic arterial buffer response (HBF), such as the impact of portal blood flow on hepatic artery flow, or assessing the intrinsic regulation of hepatic arterial blood flow by measure the hepatic arterial buffer response intraoperative in patients with or without cirrhosis using an ultrasound transit-time flowmetry, or by duplex ultrasound, Moreover studies to understand the role of hepatic flow in liver atrophy.

Impact of the presence of median arcuate ligament on biliary complications after liver transplantation.

The presence of median arcuate ligament (MAL) during orthotopic liver transplantation (OLT) may cause a significant reduction in the arterial hepatic flow. The aim of the present study is to investigate the impact of MAL on biliary complications in patients who underwent OLT. We performed a retrospective case-control study among patients who underwent OLT in Geneva University Hospital between 2007 and 2017, depending on the presence or absence of MAL. The matching was performed according to age, gender, lab-MELD score at the time of OLT and type of donor (living or dead). The presence of MAL was assessed by an expert liver radiologist on the preoperative CT angiographic evaluation. The incidence of MAL was 6.1% (19 patients). Baseline characteristics were comparable between the two groups. No significant difference in biliary complications was found between patients with and without MAL (37% and 24%, respectively). No patient presented hepatic artery thrombosis. After logistic regression, in patients with MAL, the MAL release and gastroduodenal artery preservation compared to no treatment, showed an odds ratio for post-OLT biliary complications of 1.5 and 1.25, respectively. There was no difference in overall graft survival and in hazard for biliary complications between patients with and without MAL. In the present study, we did not find any difference in the prevalence of biliary and arterial complications between patients with and without MAL. The choice of MAL treatment did not influence in a significant way the overall outcome and development of complications. However, if, at the end of arterial reconstruction, the arterial flow is not adequately established, MAL needs to be treated with the least invasive technique.

Effects of endoscopic injection sclerotherapy for esophagogastric varices on portal hemodynamics and liver function

ObjectivesTo identify patients suitable for endoscopic injection sclerotherapy (EIS) by evaluating their portal hemodynamics and liver function.MethodsWe selected 58 patients with esophagogastric varices (EGV) and liver cirrhosis (LC) related to either hepatitis C virus (C) (n = 19), hepatitis B virus (n = 2), alcohol (AL) (n = 20), C + AL (n = 6), non-alcoholic steatohepatitis (n = 6), others (n = 3), or non-LC (n = 2). All patients underwent EIS. We measured their portal venous tissue blood flow (PVTBF) and hepatic arterial tissue blood flow (HATBF) using xenon computed tomography before and after EIS. We classified them into increased group and decreased group according to the PVTBF to identify the predictors that contribute to PVTBF increase post-EIS.ResultsLow value of indocyanine green retention at 15 min (ICG-R15), the absence of paraesophageal veins, and low baseline PVTBF/HATBF (P/A) ratio predicted increased PVTBF in the multivariate logistic analysis (odds ratio (OR) 10.46, p = 0.0391; OR 12.45, p = 0.0088; OR 13.57, p = 0.0073). The protein synthetic ability improved 1 year post-EIS in increased group. Cox proportional hazards regression identified alcohol drinking (hazard ratio; 3.67, p = 0.0261) as an independent predictor of EGV recurrence.ConclusionsPatients with low ICG-R15, low P/A ratio, and the absence of paraesophageal veins were probable predictors of PVTBF improvement post-EIS. In addition, the improvement of hepatic hemodynamics likely enhanced liver function following EIS.

Contemporary Management of Median Arcuate Ligament in Liver Transplantation.

We undertook a systematic review according to the Cochrane systematic review protocol and Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We analyzed the incidence of MAL, investigations, treatment options, and potential complications associated with MAL intervention in patients undergoing OLT. After the exclusion criteria were implemented, the dataset from the final 21 manuscripts yielded 117 patients who underwent a liver transplant in the presence of MAL. The incidence of MAL in patients undergoing OLT is between 1.6% and 12%. In 63.2% of cases, an open approach for MAL intervention was undertaken. Hepatic artery thrombosis developed in 17% (7) patients without MAL intervention versus 2.6% (2) after MAL intervention. Seven grafts (5.9%) were lost after OLT in patients with MAL. Three (3.9%) patients developed arterial stenosis post-MAL intervention. We propose an algorithm for intraoperative assessment and management of liver transplant arterial inflow in the presence of MAL based on the hepatic artery flow changes with respiration, following clamping of the recipient gastroduodenal artery. In the presence of a 30%-50% flow variation on respiration, the arterial inflow should be established preserving additional inflow from the recipient gastroduodenal artery. Consider an open MAL release if the flow remains insufficient. A poor arterial flow with no variation with respiration and lack of evidence of aortoiliac atherosclerosis indicates the need for arterial jump graft.

Effect of norepinephrine infusion on hepatic blood flow and its interaction with somatostatin: an observational cohort study

BackgroundNorepinephrine (NE) is a α1-adrenergic mediated vasopressor and a key player in the treatment of perioperative hypotension. Apart from modulating systemic hemodynamics, NE may also affect regional blood flow, such as the hepatic circulation, which contains a wide variety of adrenergic receptors. It may alter regional vascular tonus and hepatic blood flow (HBF) by reducing portal vein flow (PVF) or hepatic arterial flow (HAF). The aim of this study was to assess the effects of NE on HBF.MethodsPatients scheduled for pancreaticoduodenectomy were included. All patients received standardized anesthetic care using propofol and remifentanil and were hemodynamically stabilized using a goal-directed hemodynamic strategy guided by Pulsioflex™. On surgical indication, somatostatin (SOMATO) was given to reduce pancreatic secretion. HBF measurements were performed using transit-time ultrasound (Medistim™). Baseline hemodynamic and HBF measurements were made after pancreatectomy, at T1. Afterwards, NE infusion was initiated to increase mean arterial pressure (MAP) by 10 – 20% of baseline MAP (T2) and by 20 – 30% of baseline MAP (T3). HBF and hemodynamic measurements were performed simultaneously at these three time-points.ResultsA total of 28 patients were analyzed. Administration of NE significantly increased MAP but had no effect on cardiac index. NE infusion reduced total HBF in all patients (p < 0.01) by a reduction HAF (p < 0.01), while the effect on PVF remained unclear. Post-hoc analysis showed that SOMATO-treated patients had a significant lower PVF at baseline (p < 0.05), which did not change during NE infusion. In these patients, reduction of total HBF was primarily related to a reduction of HAF (p < 0.01). In untreated patients, NE infusion reduced total HBF both by a reduction HAF (p < 0.01) and PVF (p < 0.05).ConclusionAdministration of NE reduced total HBF, by decreasing HAF, while the effect on PVF remained unclear. SOMATO-treated patients had a lower PVF at baseline, which remained unaffected during NE infusion. In these patients the decrease in total HBF with NE was entirely related to the decrease in HAF. In SOMATO-untreated patients PVF also significantly decreased with NE.Trial registrationStudy protocol EC: 2019/0395.EudraCT n°: 2018–004,139-66 (25 – 03 – 2019).Clin.trail.gov: NCT03965117 (28 – 05 – 2019).

Isolated cavaportal hepatic chemoperfusion using melphalan in the treatment of uveal melanoma liver metastases

A rare clinical observation of using hyperthermic isolated hepatic chemoperfusion is considered in the setting of a pathologically altered hepatic arterial blood flow in focal hepatic lesions caused by uveal melanoma metastases. The technical feasibility and safety of performing hyperthermic isolated hepatic chemoperfusion through the portal vein against the background of the altered hepatic arterial bed were demonstrated.

Cardiovascular Mapping in Cirrhosis From the Compensated Stage to Hepatorenal Syndrome: A Magnetic Resonance Study.

Arterial vasodilation and hyperdynamic circulation are considered hallmarks of the pathophysiological mechanisms of decompensation in cirrhosis. However, detailed characterization of peripheral, splanchnic, renal, and cardiac hemodynamic have not previously been published in a spectrum from healthy stage to advanced decompensated liver disease with hepatorenal syndrome-acute kidney injury (HRS-AKI). We included 87 patients with cirrhosis and 27 healthy controls in this prospective cohort study. The population comprised patients with compensated cirrhosis (n = 27) and decompensated cirrhosis (n = 60); patients with decompensated cirrhosis were further separated into subsets of responsive ascites (33), refractory ascites (n = 16), and HRS-AKI (n = 11). We measured portal pressure and assessed regional blood flow by magnetic resonance imaging. Patients with compensated cirrhosis experienced higher azygos venous flow and higher hepatic artery flow fraction of cardiac index than controls ( P &lt; 0.01), but other flow parameters were not significantly different. Patients with decompensated cirrhosis experienced significantly higher cardiac index ( P &lt; 0.01), higher superior mesenteric artery flow ( P = 0.01), and lower systemic vascular resistance ( P &lt; 0.001) compared with patients with compensated cirrhosis. Patients with HRS-AKI had the highest cardiac output and lowest renal flow of all groups ( P &lt; 0.01 and P = 0.02, respectively). Associations of single hemodynamic parameters were stronger with model for end-stage liver disease than with portal pressure. The regional cardiocirculatory changes seem closely linked to clinical symptoms with 3 distinguished hemodynamic stages from compensated to decompensated cirrhosis and, finally, to HRS-AKI. The attenuated renal perfusion despite high cardiac output in patients with HRS-AKI challenges the prevailing pathophysiological hypothesis of cardiac dysfunction as a causal factor in HRS-AKI. Finally, magnetic resonance imaging seems an accurate and reliable noninvasive method to assess hemodynamics and has potential as a diagnostic tool in patients with cirrhosis.

Spontaneous Intrinsic Hepatic Vascular Oscillations

The liver is well known as a large blood reservoir that can shift both stressed and unstressed volumes passively and actively in response to changes in portal venous and hepatic arterial blood flow, inflow and outflow blood pressures, autonomic nervous stimulation, and various humoral and pathophysiological factors. Not described is the characteristic of the liver to intrinsically modulate its own vascular pressure and volume independent of extrinsic factors.METHODSMale Holtzman rats (n=5) were anesthetized (30 mg/kg sodium pentobarbital, i.p.) and heparinized (500 IU/kg, i.v.), the portal vein and inferior vena cava were isolated and cannulated, the liver was flushed with room temperature normal saline, and the liver quickly removed. Each liver was mounted on a scale in a 37°C chamber (95% O2‐5% CO2) and pump‐perfused (Masterflex) with donor rat blood at a baseline 1 ml/min/g of tissue. The hepatic venous pressure (Phv) was regulated by raising and lowering the blood reservoir. At each Time (see table), portal venous oscillations were counted over 3 to 12 min and the portal venous wavelet pulse pressures (Ppv) were measured over at least 40 wavelets.RESULTSThe portal venous pressures of 3 of the 5 livers oscillated spontaneously. One lasted only 26 min while the others went on for over 200 min. The characteristics of these oscillations varied widely from animal to animal, but there usually was an irregular cycle length and uneven wavelet magnitude that tended to degrade to a diminished size with higher frequency over time (see Figure 1). Rat Time (Min) Maneuver Mean Portal Venous Pulse Pressure (mmHg) Frequency (Wavelets/Min) Frequency (Hz) Cycle Length (Sec) 1 0 Baseline 2.1 ± 0.9 (SD) 8.08 0.135 7.42 95 Baseline 1.5 ± 0.8 16.10 0.268 3.73 107 Change Phv 2.5 ± 1.3 17.00 0.283 3.53 (0 to 10 mmHg) (P&lt;0.001 vs. 95 Min Baseline) 180 Baseline 1.3 ± 0.5 18.67 0.311 3.21 2 0 Baseline 0.8 ± 0.4 14.42 0.240 4.16 60 Baseline 0.4 ± 0.3 20.00 0.333 3.00 130 Baseline 0.4 ± 0.2 23.78 0.396 2.52 3 0 Baseline 0.6 ± 0.3 8.67 0.144 6.92 CONCLUSIONSThis is a very limited data set, providing more questions than answers, but it opens a curiosity to much more investigation to understand the function of these intrinsic hepatic vascular oscillations under normal, reflex, and pathophysiological conditions.

Effect of meal intake for evaluating hepatic artery by Doppler ultrasonography in liver transplants: Does fasting matter for screening hepatic artery due to hemodynamic changes in splanchnic circulation?

The aim of this study is to assess the utility of fasting on Doppler ultrasonography findings of hepatic artery in liver transplants. Liver transplant patients without vascular abnormalities were prospectively evaluated between December 2017 and January 2020. Doppler sonography was used to describe hemodynamic changes in response to a standard meal. The diameter, peak systolic velocity, blood flow, resistive index (RI) of the main hepatic artery and portal vein peak velocity were measured. The mean hepatic arterial diameter of 44 patients was higher in the fasting group (4.5mm) than in the postprandial group (3.3mm) (p<.05). The mean hepatic arterial blood flow decreased (from .276 to .127 L/min) and hepatic arterial RI increased (from .66 to .71) following meal ingestion (p<.05). Hepatic arterial velocity was significantly lower and portal venous velocity was higher after oral intake. Meal ingestion has an important effect on hepatic artery Doppler features in liver transplants. Therefore, Doppler ultrasound evaluation should be considered after appropriate fasting due to postprandial responses of liver transplant.

First-Trimester Fetal Hepatic Artery Examination for Adverse Outcome Prediction.

Objective: To assess whether there are differences in first-trimester fetal hepatic artery flows depending on pregnancy outcomes. Methods: The prospective study conducted in 2012–2020 included 1841 fetuses from singleton pregnancies assessed during the routine first-trimester ultrasound examination (between 11- and 14-weeks’ gestation). Also, each fetus was examined to determine their hepatic artery flows by measuring the artery’s pulsatility index (HA-PI) and peak systolic velocity (HA-PSV). Results: The fetuses that were classified as belonging to the adverse pregnancy outcome group (those with karyotype abnormalities and congenital heart defects) were characterized by a significantly lower HA-PI and higher HA-PSV compared to normal outcome fetuses. Conclusion: Hepatic artery flow assessment proved to be a very useful tool in predicting adverse pregnancy outcomes, in particular karyotype abnormalities and congenital heart defects.

Hepatic artery flow, inspired oxygen, and hemoglobin determine liver tissue saturation measured with visible diffuse reflectance spectroscopy (vis‐DRS) in an in vivo swine model

Prompt diagnosis of vascular compromise following pediatric liver transplantation and restoration of oxygen delivery to the liver improves organ survival. vis-DRS allows for real-time measurement of liver tissue saturation. The current study used vis-DRS to determine changes in liver saturation during clinically relevant conditions of reduced oxygen delivery. In an in vivo swine model (n=15), we determined liver tissue saturation (St O2 ) during stepwise reduction in hepatic artery flow, different inspiratory oxygen fraction (FiO2 ), and increasing hemodilution. A custom vis-DRS probe was placed directly on the organ. Liver tissue saturation decreased significantly with a decrease in hepatic artery flow. A reduction in hepatic artery flow to 25% of baseline reduced the St O2 by 15.3±1.4% at FiO2 0.3 (mean±SE, p<.0013), and by 8.3±1.9% at FiO2 1.0 (p=.0013). After hemodilution to 7-8g/dl, St O2 was reduced by 31.8%±2.7%, p<.001 (FiO2 0.3) and 26.6±2.7%, p<.001 (FiO2 : 1.0) respectively. Portal venous saturation during low hepatic artery flow was consistently higher at FiO2 1.0. The gradient between portal venous saturation and liver tissue saturation was consistently greater at lower hemoglobin levels (7.0±1.6% per g/dl hemoglobin, p<.001). Vis-DRS showed prompt changes in liver tissue saturation with decreases in hepatic artery blood flow. At hepatic artery flows below 50% of baseline, liver saturation depended on FiO2 and hemoglobin concentration suggesting that during hepatic artery occlusion, packed red blood cell transfusion and increased FiO2 may be useful measures to reduce hypoxic damage until surgical revascularization.

Diagnosis and treatment of splenic artery steal syndrome after liver transplantation

AbstractIntroductionSplenic artery steal syndrome is a phenomenon which cause graft ischaemia and dysfunction after liver transplantation.Case PresentationA 31 year old women underwent living donor liver transplantation (LDLT) with a diagnosis of cryptogenic liver cirrhosis. In postoperative follow‐up liver enzymes were elevated. Dynamic computed tomography and digital subtraction angiography revealed splenic artery steal syndrome. Splenic artery ligation was performed for treatment.DiscussionThe diagnosis of splenic artery steal syndrome is made by the presence of slowed hepatic artery flow compared to the splenic artery without hepatic artery thrombosis or stenosis on digital subtraction angiography.ConclusionAlthough interventional radiological procedures are the first‐line treatment method, surgical treatment methods (splenectomy, splenic artery ligation) are successful in increasing hepatic artery flow.

Preliminary Results of Hepatic Blood Flow Modulation in an Experimental Model of Hepatectomy – Implications for Hepatic Artery Buffer Response Modulation

Introduction: Portal hyperperfusion of the remnant liver has been implicated in post hepatectomy liver failure (PHLF) following major hepatectomy by inducing arterial vasoconstriction, also called Hepatic Artery Buffer Response (HABR). We aimed to compare the effect of a selective A2Aadenosine receptor agonist Regadenoson to a porto-caval (P-C) shunt in an experimental model of hepatectomy in piglets on hepatic blood flow modulation. Methods: A cohort study with cross-over design of serial doppler measurements in landrace pigs weighing 25-30 Kg was performed; all subjects underwent laparotomy and baseline measurements were taken. Thereafter extended left hepatectomy with P-C shunt was performed and measurements were repeated. Finally, the P-C shunt was occluded and all animals were administered intra-arterially 400mcg of regadenoson, prior repeating measurements. Results: The baseline portal vein and hepatic artery flow were 28.5 ± 7.47 ml/sec and 118.66 ± 19.28 ml/sec respectively. After hepatectomy a significant increase of the portal vein flow by 91.8% while the hepatic artery flow increase only by 26.4%, signifying activation of the HABR. Opening of the P-C shunt decreased the portal vein flow by 24.69% and a more pronounced decrease of hepatic artery flow (34.22%). After occlusion of the portocaval shunt and administration of regadenoson there was a minor decrease of the portal flow by 13.71% while there was a significant drop of the hepatic artery flow by 55.33%, thus more effectively decreasing arterial vasoconstriction (p<0.005). Conclusion: Regadenoson can more effectively decrease hepatic artery flow than PC shunt, thus signifying a potential role in the management of PHLF.

Diagnostic Imaging of Biliary Atresia

담도폐쇄증은 신생아 담즙 정체의 드물지만 중요한 원인이다. 적절한 치료와 예후를 위해서는 정확한 조기 진단이 중요하다. 본 종설에서는 초음파 검사, MRI, 간담도 핵의학스캔, 담관조영술 등의 영상 검사에서 담도폐쇄증의 영상 소견을 검토하였다. 지금까지 알려진 주요 영상의학적 소견들은 담낭의 비정상적인 모양과 크기, 간문맥 주변의 비후를 나타내는 ‘triangular cord’ sign, 총담관이 보이지 않고, 간동맥 혈류가 증가하는 소견 등과 함께 동반된 기형의 유무들을 보이는 것이다. 담도폐쇄증의 진단을 위해 초음파 검사, MRI, 간담도 핵의학스캔, 담관조영술 등의 여러 영상 검사들을 시행하며, 1차 영상 검사로 초음파 검사가 중요하다. 본 종설에서는 각 영상 검사들에서 지금까지 알려진 담도폐쇄증의 소견들과 함께 조기 신생아기에서 담도폐쇄증 진단의 어려움, 그리고 간 섬유화를 예측하기 위한 영상의 역할도 검토하였다. 본 종설이 담도폐쇄증 진단에 도움이 되길 바란다.

Two pumps or one pump? A comparison of human liver normothermic machine perfusion devices for transplantation.

Normothermic machine perfusion provides continuous perfusion to ex situ hepatic grafts through the portal vein and the hepatic artery. Because the portal vein has high flow with low pressure and the hepatic artery has low flow with high pressure, different types of perfusion machines have been employed to match the two vessels' infusion hemodynamics. We compared transplanted human livers perfused through a 2-pump (n=9) versus a 1-pump perfusion system (n=6) where a C-clamp is used as a tubing constrictor to regulate hemodynamics. There was no significant difference between groups in portal vein or hepatic artery flow rate. The 1-pump group had more hemoglobin in the perfusate. However, there was no significant difference in plasma hemoglobin between the 2-pump and 1-pump groups at each time point or in the change in levels, proving no hemolysis occurred due to C-clamp tube constriction. After transplantation, the 2-pump group had two cases of early allograft dysfunction (EAD), whereas the 1-pump group had no EAD. There was no graft failure or patient death in either group during follow-up ranging from 20-52months. Our data show that the 1-pump design provided the same hemodynamic output as the 2-pump design, with no additional hemolytic risk, but with the benefits of lower costs, easier transport and faster and simpler setting.

Hepatic pseudolesions caused by alterations in intrahepatic hemodynamics

Hepatic pseudolesion may occur in contrast-enhanced computed tomography and magnetic resonance imaging due to the unique haemodynamic characteristics of the liver. The concept of hepatic arterial buffer response (HABR) has become mainstream for the understanding of the mechanism of the reciprocal effect between hepatic arterial and portal venous flow. And HABR is thought to be significantly related to the occurrence of the abnormal imaging findings on arterial phase of contrast enhanced images, such as hepatic arterial-portal vein shunt and transient hepatic attenuation difference, which mimic hypervascular tumor and may cause clinical problems. Third inflow to the liver also cause hepatic pseudolesion, and some of the cases may show histopathologic change such as focal hyperplasia, focal fatty liver, and focal sparing of fatty liver, and called pseudotumor. To understand these phenomena might be valuable for interpreting the liver imaging findings.

Quantitative contrast-enhanced ultrasound for the evaluation and early detection of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy with high mortality mainly due to pre-existing liver disease and delay in diagnosis, limiting treatment options. Currently, the state-of-the-art diagnostic metric for HCC is LiRADS (Liver Imaging Reporting and Data System), a qualitative image assessment based on the bolus transit characteristics of microbubbles that stratifies liver tumors suspected for HCC. However, with contrast-enhanced ultrasound, liver tumor perfusion can be quantifiably characterized to identify abnormal arterial flow after an initial portal venous and hepatic arterial flow reduction in the liver, which are typical features of HCCs. The image intensity in a region of interest (ROI) in the HCC is used to form a time-intensity curve (TIC) of the bolus transit (wash-in/washout). A lognormal curve is fitted to the TIC and parameters related to blood flow in the tumor are extracted. Respiratory gating and motion compensation are applied to the video loops before forming the TIC to remove noise and improve the accuracy of the HCC perfusion measurements. Parametric images of the rise time and peak intensity provide an HCC classification algorithm. Utilizing this approach, we provide an improvement to the LiRADS method for an earlier and more accurate diagnosis of HCC.

SPLENIC ARTERY SYNDROME AFTER LIVER TRANSPLANTATION – PREDICTIVE FACTORS: EXPERIENCE OF A CENTER

Splenic artery syndrome (SAS) is described as a decrease in hepatic artery (HA) flow associated with increased flow in the splenic artery (SA). The present study aim was to identify predictive factors of SAS. A retrospective study was conducted in 70 patients, undergoing liver transplantation (LT) between 03/2010 until 08/2016. The case group (n=27) corresponded to the patients who developed SAS and the control group (n=43) to the patients who didn’t develop. The donor, recipient and graft variables were collected. Significant differences were observed in relation to spleen volume 1137,4±512,9) cm3 vs 523,9±258,1cm3, spleen volume/ liver volume ratio 0,9±0,3 vs 0,4±0,2, difference in caliber between SA and HA 2,1±1,6mm vs 0,8±1,5mm, and the ratio between spleen volume and body mass index (BMI) of the recipient 47,9±24,5 vs 18,9±8,8 between the case and control group respectively. In case group the mean difference between pre-embolization and post-embolization resistive index (RI) was 0.2±0.1, which demonstrates a significant improvement after embolization of the SA (p<0.001, CI: 95% 0.11-0.25). In logistic regression, the retained variable was only the spleen volume (p<0.05), and the cut-off point was 1023.9 cm3. It’s possible to conclude that spleen volume is a risk factor for SAS. It’s also important to note that significant differences between groups were evident in relation to the ratio spleen volume/liver volume and difference in caliber between SA and HA in the pre-LT. In this sense, it’s relevant in future studies to develop a prospective methodological design in order to analyze the predictive value of these variables.

Resection and reconstruction of pancreatic artery aneurysms caused by the compression of the celiac trunk by the median arcuate ligament: a report of two cases

BackgroundSome patients with the compression of the celiac trunk by the median arcuate ligament (MAL) suffer pancreatic artery aneurysms (PAAs) due to excessive blood flow from the superior mesenteric artery. These aneurysms are in peril because they are prone to rupture irrespective of size. Here, we present two cases of resection and reconstruction of PAAs caused by the compression of the celiac trunk by the MAL.Case presentationPatient 1 was a 44-year-old man who was first diagnosed to have a visceral artery aneurysm with a diameter of 4 cm accidentally found by ultrasound examination at a regular medical check-up. Contrast-enhanced CT revealed the compression of the celiac trunk by the MAL and a PAA originating from the first jejunal artery. First, laparoscopic excision of the MAL followed by a stent placement into the celiac trunk was performed. Although the stent was patent, the PAA still grew. The patient underwent resection and reconstruction of the PAA. Reconstruction of the pancreatic arterial arcade was needed because clamping of the inferior pancreaticoduodenal artery (IPDA) resulted in disappearance of the hepatic arterial blood flow. The follow-up CT 2 years and 9 months after the operation revealed no recurrence of aneurysms and the patent anastomosis. Patient 2 was a 68-year-old man who presented with an epigastric pain. Contrast-enhanced CT revealed the compression of the celiac trunk by the MAL and a PAA approximately 6 cm in diameter originating from the IPDA. The PAA was surrounded by a relatively low-intensity area, suggesting impending rupture of the PAA. The patient underwent resection and reconstruction of the PAA under an emergency situation. Reconstruction of the pancreatic arterial arcade was needed because clamping of the inflow IPDA resulted in disappearance of the hepatic blood flow. The follow-up CT 1 year and 8 months after the operation revealed no recurrence of aneurysms and the patent anastomosis.ConclusionsAlthough long-term follow-up is needed, resection and reconstruction is one of the therapeutic choices for PAAs caused by the compression of the celiac trunk by the MAL in order to prevent catastrophic aneurysm rupture.