Evaluation of computed tomography arterial portography scan timing using different bolus tracking methods.

Computed tomography arterial portography (CTAP) is widely used with a fixed scan timing and contrast medium quantity; however, these parameters are not necessarily optimal. In this study, CTAP scan timing was analyzed by different bolus tracking methods to monitor the inflow of the contrast medium in real-time. A total of 249 patients who underwent CTAP were assessed. In 30 patients, the CTAP scanning began 33 s after contrast medium injection started (fixed method). In 74 patients, the regions of interest (ROIs) were established at two places in the inferior vena cava above the hepatic vein (inferior vena cava-ROI method). In 145 patients, the ROI was established at two places in the liver parenchyma (liver parenchyma-ROI method). Scan timing was considered appropriate when the difference in the CT value between the hepatic and portal veins approached 0; this was observed significantly more with the liver parenchyma-ROI method than with the other methods. CTAP scan timing with the liver parenchyma-ROI method was better than that with the fixed and inferior vena cava-ROI methods.

Percutaneous Portal Vein Embolization Using a Simplified Sheathless 18-Gauge Trocar Needle Approach: Review of Efficacy and Safety.

PURPOSE: Portal vein (PV) embolization (PVE) is traditionally performed via a PV sheath with selective embolization of PV branches. Here, the efficacy and safety of PVE with the use of only an 18-gauge needle is reported. MATERIALS AND METHODS: Consecutive patients who underwent PVE from 2009 through 2017 were retrospectively reviewed. Forty-five patients (mean age, 60 y ± 7.6; 38 men) underwent 45 PVE procedures. Hepatocellular carcinoma, cholangiocarcinoma, and metastases accounted for 26 (58%), 13 (29%), and 6 (13%) patients, respectively. PVE was performed by puncturing a branch of right PV with an 18-gauge needle under US guidance. Via the same needle, direct portography was performed, followed by PVE with an N-butyl cyanoacrylate/Lipiodol mixture. Percentage increase of future liver remnant (FLR) volume and increase in ratio of FLR to total liver volume were estimated as measures of efficacy. Complications were reported according to Society of Interventional Radiology classification. Fluoroscopy time, procedure time, and dose-area product (DAP) were recorded. RESULTS: Technical success rate was 100%. The median DAP, fluoroscopy time, and procedure time were 74,387 mGy·cm2 (IQR, 90,349 mGy·cm2), 3.5 min (IQR, 2.10 min), and 24 min (IQR, 10.5 min). Among the 23 patients with complete CT volumetry data, mean increase in the ratio of FLR to total liver volume and percentage increase of FLR volume were 12.5% ± 7.7 and 50% ± 33, respectively. There were 3 minor complications (asymptomatic nonocclusive emboli in FLR) and 3 major complications (1 hepatic vein emboli, 1 subphrenic collection, and 1 hepatic infarct). CONCLUSIONS: PVE via a sheathless 18-gauge needle approach is feasible, with satisfactory FLR hypertrophy.

Evaluation of hepatic tumor portal perfusion using mesenteric angiography: A pilot study in 5 dogs.

BACKGROUND: Mesenteric angiography is a sensitive method for visualizing portal perfusion in the dog. OBJECTIVES: To evaluate hepatic portal perfusion in dogs with incompletely resectable hepatic tumors using mesenteric angiography. ANIMALS: Five client-owned dogs with incompletely resectable hepatic tumors evaluated with mesenteric angiography. METHODS: Retrospective case series. Electronic medical records at the Animal Medical Center were analyzed to identify dogs that underwent mesenteric portography to determine blood flow to nonresectable hepatic tumors and subsequently determine ideal routes for transarterial embolization, vascular stent placement, or both. The images obtained from mesenteric angiography were analyzed and compared to those obtained from computed tomography angiography. RESULTS: Portography was accomplished using direct mesenteric venography in 3 dogs with hepatocellular carcinoma (HCC), cranial mesenteric arteriography in 1 dog with hepatic adenoma or well-differentiated HCC, and via splenic arteriovenous fistula in 1 dog with diffuse hepatic hemangiosarcoma metastases. Mean pixel densities in areas of hepatic tumor growth identified statistically significant decreases in portal blood flow (P = .02) compared to normal hepatic parenchyma. CONCLUSIONS AND CLINICAL IMPORTANCE: Initial findings indicate that the blood supply to large and metastatic hepatic tumors in dogs may correlate with that in humans, such that the majority of the tumor blood supply arises from the hepatic artery and not the portal vein. Differences in blood supply between normal hepatic parenchyma and hepatic tumors might be exploited by developing selective tumor therapies such as arterial embolization or chemoembolization that largely spare normal liver tissue. Further investigation is warranted.

Splenic vein reconstruction is unnecessary in pancreatoduodenectomy combined with resection of the superior mesenteric vein-portal vein confluence according to short-term outcomes.

BACKGROUND: Superior mesenteric vein-portal vein confluence resection combined with pancreatoduodenectomy (SMPVrPD) is occasionally required for resection of pancreatic head tumors. It remains unclear whether such situations require splenic vein (SV) reconstruction for decompression of left-sided portal hypertension (LSPH). METHODS: The data from 93 of 104 patients who underwent pancreatoduodenectomy (PD) for pancreatic head malignancies were reviewed. Surgical outcomes in three groups-standard PD (control group), PD combined with vascular resection and SV preservation (SVp group), and SMPVrPD with SV resection (SVr group)-were compared. The influence of division and preservation of the two natural confluences (left gastric vein-portal vein and/or inferior mesenteric vein-SV confluences) on portal hemodynamics were evaluated using three-dimensional computed tomographic portography. RESULTS: No mortality occurred. The morbidity rates were not significantly different among the three groups (18/43, 8/21, and 7/29, respectively; p = 0.306). In the SVr group, three patients had gastric remnant venous congestion, and three had esophageal varices without hemorrhagic potential. No patients had splenomegaly, or severe or prolonged thrombocytopenia. These LSPH-associated findings were less frequently observed when the two confluences were preserved. CONCLUSIONS: SMPVrPD without SV reconstruction can be safely conducted. Additionally, preservation of these two confluences may reduce the risk of LSPH.

Extrahepatic Arteries Originating from Hepatic Arteries: Analysis Using CT During Hepatic Arteriography and Visualization on Digital Subtraction Angiography.

PURPOSE: To investigate the prevalence and site of origin of extrahepatic arteries originating from hepatic arteries on early phase CT during hepatic arteriography (CTHA) was accessed. Visualization of these elements on digital subtraction hepatic angiography (DSHA) was assessed using CTHA images as a gold standard. MATERIALS AND METHODS: A total of 943 patients (mean age 66.9 ± 10.3 years; male/female, 619/324) underwent CTHA and DSHA. The prevalence and site of origin of extrahepatic arteries were accessed using CTHA and visualized using DSHA. RESULTS: In 924 (98.0%) patients, a total of 1555 extrahepatic branches, representing eight types, were found to originate from hepatic arteries on CTHA. CTHA indicated the following extrahepatic branch prevalence rates: right gastric artery, 890 (94.4%); falciform artery, 386 (40.9%); accessory left gastric artery, 161 (17.1%); left inferior phrenic artery (IPA), 43 (4.6%); posterior superior pancreaticoduodenal artery, 33 (3.5%); dorsal pancreatic artery, 26 (2.8%); duodenal artery, 12 (1.3%); and right IPA, 4 (0.4%). In addition, 383 patients (40.6%) had at least one undetectable branch on DSHA. The sensitivity, specificity, and accuracy of visualization on DSHA were as follows: RGA, 80.0, 86.8, and 80.4%; falciform artery, 53.9, 97.7, and 80.0%; accessory LGA, 64.6, 98.6, and 92.3%; left IPA, 76.7, 99.8, and 98.7%; PSPDA, 100, 99.7, and 99.9%; dorsal pancreatic artery, 57.7, 100, and 98.8%; duodenal artery, 8.3, 99.9, and 98.7%; and right IPA, 0, 100, and 99.6%, respectively. CONCLUSION: Extrahepatic arteries originating from hepatic arteries were frequently identified on CTHA images. These arteries were frequently overlooked on DSHA.

Preconditioning by portal vein embolization modulates hepatic hemodynamics and improves liver function in pigs with extended hepatectomy.

BACKGROUND: Portal vein embolization is performed weeks before extended hepatic resections to increase the future liver remnant and prevent posthepatectomy liver failure. Portal vein embolization performed closer to the operation also could be protective, but worsening of portal hyper-perfusion is a major concern. We determined the hepatic hemodynamic effects of a portal vein embolization performed 24 hours prior to hepatic operation. METHODS: An extended (90%) hepatectomy was performed in swine undergoing (portal vein embolization) or not undergoing (control) a portal vein embolization 24 hours earlier (n = 10/group). Blood tests, hepatic and systemic hemodynamics, hepatic function (plasma disappearance rate of indocyanine green), liver histology, and volumetry (computed tomographic scanning) were assessed before and after the hepatectomy. Hepatocyte proliferating cell nuclear antigen expression and hepatic gene expression also were evaluated. RESULTS: Swine in the control and portal vein embolization groups maintained stable systemic hemodynamics and developed similar increases of portal blood flow (302 ± 72% vs 486 ± 92%, P = .13). Portal pressure drastically increased in Controls (from 9.4 ± 1.3 mm Hg to 20.9 ± 1.4 mm Hg, P < .001), while being markedly attenuated in the portal vein embolization group (from 11.4 ± 1.5 mm Hg to 16.1 ± 1.3 mm Hg, P = .061). The procedure also improved the preservation of the hepatic artery blood flow, liver function, and periportal edema. These effects occurred in the absence of hepatocyte proliferation or hepatic growth and were associated with the induction of the vasoprotective gene Klf2. CONCLUSION: Portal vein embolization preconditioning represents a potential hepato-protective strategy for extended hepatic resections. Further preclinical studies should assess its medium-term effects, including survival. Our study also supports the relevance of hepatic hemodynamics as the main pathogenetic factor of post-hepatectomy liver failure.

Portal Vein Thrombosis and Arterioportal Shunting Due To Chronic Cholangitis: A Rare Complication of Living-Donor Liver Transplant.

OBJECTIVES: We present a patient with portal vein thrombosis due to chronic cholangitis after undergoing a living-donor liver transplant. CASE PRESENTATION: A 52-year-old woman with a history of hepatitis B virus-related liver cirrhosis underwent a living-donor liver transplant. After the surgery, the patient had recurrent episodes of cholangitis because of common and intrahepatic bile duct stricture. Biliary stricture because of cholangitis eventually resulted in acute portal vein thrombosis. A stent was inserted by percutaneous transluminal portography. Blood flow through the portal vein progressively improved from the third through the 10th day after stent placement. The anticoagulation regimen was change to acetylsalicylic acid and clopidogrel hydrogen sulfate (Plavix). On poststenting day 10, a follow-up computed tomographic scan showed good patency of the main portal vein and no evidence of arterioportal shunting. CONCLUSIONS: Cholangitis after living-donor liver transplant is a rare cause of portal vein thrombosis. Regular follow-up examinations with color Doppler ultrasound are required to monitor portal vein flow in patients with biliary complications after living-donor liver transplant.

Therapeutic efficacy and stent patency of transhepatic portal vein stenting after surgery.

AIM: To evaluate portal vein (PV) stenosis and stent patency after hepatobiliary and pancreatic surgery, using abdominal computed tomography (CT). METHODS: Percutaneous portal venous stenting was attempted in 22 patients with significant PV stenosis (> 50%) - after hepatobiliary or pancreatic surgery - diagnosed by abdominal CT. Stents were placed in various stenotic lesions after percutaneous transhepatic portography. Pressure gradient across the stenotic segment was measured in 14 patients. Stents were placed when the pressure gradient across the stenotic segment was > 5 mmHg or PV stenosis was > 50%, as observed on transhepatic portography. Patients underwent follow-up abdominal CT and technical and clinical success, complications, and stent patency were evaluated. RESULTS: Stent placement was successful in 21 patients (technical success rate: 95.5%). Stents were positioned through the main PV and superior mesenteric vein (n = 13), main PV (n = 2), right and main PV (n = 1), left and main PV (n = 4), or main PV and splenic vein (n = 1). Patients showed no complications after stent placement. The time between procedure and final follow-up CT was 41-761 d (mean: 374.5 d). Twenty stents remained patent during the entire follow-up. Stent obstruction - caused by invasion of the PV stent by a recurrent tumor - was observed in 1 patient in a follow-up CT performed after 155 d after the procedure. The cumulative stent patency rate was 95.7%. Small in-stent low-density areas were found in 11 (55%) patients; however, during successive follow-up CT, the extent of these areas had decreased. CONCLUSION: Percutaneous transhepatic stent placement can be safe and effective in cases of PV stenosis after hepatobiliary and pancreatic surgery. Stents show excellent patency in follow-up abdominal CT, despite development of small in-stent low-density areas.

Endovascular Reconstruction of Extrahepatic Portal Vein in Noncirrhotic and Nonmalignant Chronic Portal Vein Thrombosis Secondary to an Iatrogenic Stenotic Lesion.

Portal vein (PV) thrombosis (PVT) in the absence of liver disease or thrombophilia is rare. We report a 57-year-old male with a history of stage 3 chronic kidney disease who presented at the emergency department 18 months after abdominal surgery with progressive abdominal pain and distention. Computed tomography revealed PVT with multiple collaterals and moderate ascites. He had undergone partial gastrectomy and gastrojejunal anastomosis at an outside facility for gastrointestinal stromal tumors that caused an iatrogenic stenotic lesion in the PV. The patient underwent balloon angioplasty and endovascular deployment of an 8 mm × 100 mm Viabahn covered stent (W. L. Gore and Associates, Flagstaff, Arizona) in the extrahepatic PV via a transhepatic approach; the device allowed complete restoration of prograde portal flow with clinical improvement. At 6 months from the intervention, he remains symptom-free with normal liver function tests and patent endoprosthesis on antiplatelet therapy.

Prediction of Embolization Area after Conventional Transcatheter Arterial Chemoembolization for Hepatocellular Carcinoma Using SYNAPSE VINCENT.

PURPOSE: Transcatheter arterial chemoembolization (TACE) is one of the most effective therapeutic options for hepatocellular carcinoma (HCC) and it is important to protect residual liver function after treatment as well as the effect. To reduce the liver function deterioration, we evaluated the automatic software to predict the embolization area of TACE in 3 dimensions. MATERIALS AND METHODS: Automatic prediction software of embolization area was used in chemoembolization of 7 HCCs. Embolization area of chemoembolization was evaluated within 1 week CT findings after TACE and compared simulated area using automatic prediction software. RESULTS: The maximal diameter of these tumors is in the range 12-42 mm (24.6 ± 9.5 mm). The average time for detecting tumor-feeding branches was 242 s. The total time to detect tumor-feeding branches and simulate the embolization area was 384 s. All cases could detect all tumor-feeding branches of HCC, and the expected embolization area of simulation with automatic prediction software was almost the same as the actual areas, as shown by CT after TACE. CONCLUSION: This new technology has possibilities to reduce the amount of contrast medium used, protect kidney function, decrease radiation exposure, and improve the therapeutic effect of TACE.

Diagnostic performance of gadoxetic acid (Primovist)-enhanced MR imaging versus CT during hepatic arteriography and portography for small hypervascular hepatocellular carcinoma.

To compare the diagnostic performance of gadoxetic acid-enhanced magnetic resonance imaging (MRI) with that of computed tomography (CT) during hepatic arteriography and arterial portography (CT HA/AP) for detecting hepatocellular carcinoma (HCC) from small hypervascular nodules.This retrospective study included 38 patients with 131 hypervascular nodules (≤2 cm) who had underwent MRI and CT HA/AP within a 2-week interval. Two observers analyzed MRI while other 2 observers analyzed CT HA/AP. Thereafter, MRI observers reviewed the CT HA/AP and magnetic resonance (MR) images again using both modalities. HCC was diagnosed by pathologic or imaging studies according to American Association for the Study of Liver Diseases (AASLD) criteria. Alternative free-response receiver operating characteristic (ROC) analysis was performed on a lesion-by-lesion basis. Diagnostic accuracy (area under the ROC curve [Az]), sensitivity, specificity, and positive and negative predictive values were calculated.The pooled Az was significantly higher for the combined modalities (0.946) than for MRI alone (0.9, P = 0.004), and for MRI than for CT HA/AP alone (0.827, P = 0.0154). Subgroup analysis for HCC ≤1 cm showed the sensitivity of the combined modalities (79.4%) was significantly higher than for MRI (52.9%) and CT HA/AP alone (50%) (both, P < 0.005). The specificity of the combined modalities was not different from MRI alone (98.8% vs. 97.3%, P = 0.5), but was significantly higher than for CT HA/AP alone (98.8% vs. 92.5%, P = 0.022).Hypervascular HCCs >1 to 2 cm can be diagnosed sufficiently by MRI. The combined modalities increased the diagnostic accuracy of HCCs ≤1 cm, compared with MRI or CT HA/AP alone.

Prognostic Significance of Concurrent Hypovascular and Hypervascular Nodules in Patients with Hepatocellular Carcinoma.

BACKGROUND: Hypovascular nodules often occur together with hypervascular hepatocellular carcinoma (HCC). However, it remains controversial whether hypovascular nodules associated with hypervascular HCC have any prognostic value. This study evaluated the prognostic impact of hypovascular nodules co-existing with hypervascular HCC as diagnosed by computed tomography during arterial portography (CTAP) and computed tomography during hepatic arteriography (CTHA), which can sensitively capture the dynamic changes in blood flow through the portal vein and hepatic artery in patients with early stage HCC. METHODS: A total of 152 patients with hypervascular HCC (≤ 30 mm, ≤ 3 nodules), who underwent initial local ablation, were analyzed retrospectively. All patients received CTAP and CTHA prior to treatment. Overall survival (OS) was compared among group A (hypervascular HCC only, 107 patients) and group B (hypovascular nodules and hypervascular HCC, 45 patients). RESULTS: Among all hypovascular nodules, 81% (46 of 57) developed hypervascularization within the follow-up period. The 1- and 2-year hypervascularization rates were 17% and 51%, respectively. OS was significantly longer for group A than for group B (P < 0.001). A Cox proportional-hazards model identified the presence of hypovascular nodules concurrent with hypervascular HCC as an independent poor prognostic factor. CONCLUSION: The prognosis of hypervascular HCC patients with hypovascular nodules detected during CTAP and CTHA is poor. Clinical HCC categories seem to be dissimilar between patients with and without hypovascular nodules.

Shunt porto-sistémico congénito en hígado no cirrótico como causante de síndrome confusional agudo reiterado: report of one case / Portosystemic shunt in a normal liver causing confusional states

Portosystemic shunts are rare vascularization disorders, and an uncommon cause of confusional states. We report an 87-year-old male with a previously normal cognitive status who was repeatedly admitted for sudden symptoms of disorientation and functional limitation. The patient had high ammonium levels which lead to the suspicion of the presence a portosystemic shunt, even in the absence of pre-existing liver disease. A contrast enhanced computed tomography of the abdomen confirmed the presence an abnormal communication of the right portal vein with the suprahepatic veins. The communication was embolized and the confusional states of the patient subsided.

Image fusion-guided portal vein puncture during transjugular intrahepatic portosystemic shunt placement.

PURPOSE: The purpose of this study was to assess the feasibility and utility of image fusion (Easy-TIPS) obtained from pre-procedure CT angiography and per-procedure real-time fluoroscopy for portal vein puncture during transjugular intrahepatic portosystemic shunt (TIPS) placement. MATERIALS AND METHODS: Eighteen patients (15 men, 3 women) with a mean age of 63 years (range: 48-81 years; median age, 65 years) were included in the study. All patients underwent TIPS placement by two groups of radiologists (one group with radiologists of an experience<3 years and one with an experience≥3 years) using fusion imaging obtained from three-dimensional computed tomography angiography of the portal vein and real-time fluoroscopic images of the portal vein. Image fusion was used to guide the portal vein puncture during TIPS placement. At the end of the procedure, the interventional radiologists evaluated the utility of fusion imaging for portal vein puncture during TIPS placement. Mismatch between three-dimensional computed tomography angiography and real-time fluoroscopic images of the portal vein on image fusion was quantitatively analyzed. Posttreatment CT time, number of the puncture attempts, total radiation exposure and radiation from the retrograde portography were also recorded. RESULTS: Image fusion was considered useful for portal vein puncture in 13/18 TIPS procedures (72%). The mean posttreatment time to obtain fusion images was 16.4minutes. 3D volume rendered CT angiography images was strictly superimposed on direct portography in 10/18 procedures (56%). The mismatch mean value was 0.69cm in height and 0.28cm laterally. A mean number of 4.6 portal vein puncture attempts was made. Eight patients required less than three attempts. The mean radiation dose from retrograde portography was 421.2dGy.cm2, corresponding to a mean additional exposure of 19%. CONCLUSION: Fusion imaging resulting from image fusion from pre-procedural CT angiography is feasible, safe and makes portal puncture easier during TIPS placement.

Graft Failure From Hepatic Veno-Occlusive Disease After a Liver Transplant: A Case Report.

OBJECTIVES: Hepatic veno-occlusive disease after liver transplant is rare but potentially fatal. Here, we describe a case of veno-occlusive disease occurring after a liver transplant patient, which resulted in graft failure. CASE REPORT: A 44-year-old woman developed severe ascites accompanied with jaundice, for 1 month after a liver transplant that could not be explicated by common complications. Veno-occlusive disease was diagnosed basing on clinical, pathologic, and radiologic findings. The definitive pathogenesis was difficult to determine. The patient could not show any response to medical therapy, and her deteriorated clinical condition developed to hepatic failure, which called for retransplant. CONCLUSIONS: Veno-occlusive disease after a liver transplant can result in graft failure, and re-transplant may be the only alternative resource in critical case.

Contrast enhanced computed tomography and reconstruction of hepatic vascular system for transjugular intrahepatic portal systemic shunt puncture path planning.

AIM: To describe a method for the transjugular intrahepatic portal systemic shunt (TIPS) placement performed with the aid of contrast-enhanced computed tomography (CECT) and three-dimensional reconstructed vascular images (3D RVIs), and to assess its safety and effectiveness. METHODS: Four hundred and ninety patients were treated with TIPS between January 2005 and December 2012. All patients underwent liver CECT and reconstruction of 3D RVIs of the right hepatic vein to portal vein (PV) prior to the operation. The 3D RVIs were carefully reviewed to plan the puncture path from the start to target points for needle pass through the PV in the TIPS procedure. RESULTS: The improved TIPS procedure was successful in 483 (98.6%) of the 490 patients. The number of punctures attempted was one in 294 (60%) patients, 2 to 3 in 147 (30%) patients, 4 to 6 in 25 (5.1%) patients and more than 6 in 17 (3.5%) patients. Seven patients failed. Of the 490 patients, 12 had punctures into the artery, 15 into the bile duct, eight into the gallbladder, and 18 through the liver capsule. Analysis of the portograms from the 483 successful cases indicated that the puncture points were all located distally to the PV bifurcation on anteroposterior images, while the points were located proximally to the bifurcation in the three cases with intraabdominal bleeding. The complications included three cases of bleeding, of whom one died and two needed surgery. CONCLUSION: Use of CECT and 3D RVIs to plan the puncture path for TIPS procedure is safe, simple and effective for clinical use.

Prospective diagnostic test accuracy comparison of computed tomography during arterial portography and Primovist magnetic resonance imaging in the pre-operative assessment of colorectal cancer liver metastases.

OBJECTIVES: To assess and compare the accuracy and inter-observer agreement for the detection of liver lesions using Primovist magnetic resonance imaging (pMRI) and computed tomography during arterial portography (CTAP). METHODS: Patients evaluated at St George Hospital Liver Unit for colorectal liver metastases (CRCLM) underwent CTAP as part of standard staging. pMRI was added to the pre-operative assessment. Two radiologists reported CTAP and two reported pMRI. The sensitivity and specificity of CTAP and pMRI were calculated using histopathology as the gold standard. RESULTS: Complete data were available for 62 patients corresponding to 219 lesions confirmed on histopathology. Agreement on the detection of lesions between the two radiologists that reported pMRI was higher than for CTAP (Kappa = 0.80 versus 0.74). Specificity of lesion detection for pMRI was 0.88 and 0.83 for CTAP (P = 0.112). Sensitivity for pMRI was 0.83 and 0.81 for CTAP. For patients who had chemotherapy before evaluation, pMRI had a significantly higher specificity than CTAP (0.79 versus 0.63, P = 0.011). CONCLUSIONS: pMRI is less invasive, has a good inter-observer agreement, has comparable sensitivity and specificity to CTAP in the pre-chemotherapy population and demonstrates better specificity in patients assessed post-chemotherapy. pMRI is a valid alternative to CTAP in the assessment of CRCLM.