Segmental Hepatic Artery Research Articles

Main versus segmental hepatic artery angioembolization in patients with traumatic liver injuries: A Western Trauma Association multicenter study

IntroductionHepatic angioembolization is highly effective for hemorrhage control in hemodynamically stable patients with traumatic liver injuries and contrast extravasation. However, there is a paucity of data regarding the specific location of angioembolization within the hepatic arterial vasculature and its implications on patient outcomes. MethodsA post-hoc analysis of a multicenter prospective observational study across 23 centers was performed. Adult patients undergoing main hepatic artery angioembolization or segmental hepatic artery angioembolization within 8 hours of arrival were included. The primary outcome was liver-related complications, defined as perihepatic fluid collection, bile leak/biloma, pseudoaneurysm, hepatic necrosis, and/or hepatic abscess. Secondary outcomes were liver-related complication interventions, length of stay, and mortality. ResultsA total of 55 patients underwent hepatic angioembolization, with 23 (41.8%) undergoing main hepatic artery angioembolization and 32 (58.2%) receiving segmental hepatic artery angioembolization. Both groups were comparable in age, vitals, mechanism of injury, liver injury grade distribution, and injury severity score (all P > .05). The main hepatic artery angioembolization group had greater rates of overall liver-related complications (65.2% vs 31.2%, P = .039), specifically perihepatic fluid collection (26.1% vs 6.3%, P = .040) and bile-leak/biloma (34.8% vs 12.5%, P = .048). Main hepatic artery angioembolization had greater rates of 2 or more liver-related complications (47.8% vs 9.4%, P = .001) and readmission within 30 days (30.4% vs 9.4%, P = .046). No significant differences were observed in hospital length of stay and mortality (all P > .05). ConclusionsMain hepatic artery angioembolization is associated with increased rates of liver-related complications, multiple liver-related complications, and readmission within 30 days compared with segmental hepatic artery angioembolization. Thus, main hepatic artery angioembolization should be reserved for use only when segmental hepatic artery angioembolization is not feasible, albeit with significantly increased morbidity.

Development of a Novel Ex Vivo Porcine Hepatic Segmental Perfusion Proof-of-Concept Model Towards More Ethical Translational Research.

Introduction Ex vivo machine perfusion describes the technique where organs are continuously perfused and oxygenated extracorporeally (at physiological conditions) to maintain the organs' viability. To our knowledge, there are currently no reported studies describing ex vivo perfusion of a single hepatic segment. Here, we describe the development of a porcine ex vivo hepatic segmental perfusion model to demonstrate proof of concept and support further research into the ex vivo perfusion of the human liver using discarded tissue. Methods Whole livers were retrieved from abattoir-derived pigs and connected to a normothermic extracorporeal perfusion circuit. Constant segmental perfusion via the common or segmental hepatic artery and portal vein with heparinised autologous blood was established. The viability of the perfused organ was assessed by monitoring perfusion pressures, flow rates and histology samples. Results Following perfusion and optimisation of the model for three hepatic segments, the third perfusion demonstrated viable hepatocytes centrally after 4 hof segmental perfusion. Conclusion Ex vivo hepatic segmental perfusion is technically challenging but its success in a porcine model and the principles learned should facilitate the development of an analogous human model using discarded tissue following formal liver resections. The model would usea healthy liver segment following a major formal resection such as a hemi-hepatectomy and ex vivo perfusion performed via a segmental hepatic artery and portal vein. If successful this model would represent a significant development and enableethical translation research to assess the response of human livers to a variety of stressors, including toxicity and infection.

A O03 Ex vivo perfusion of isolated human liver segments: the development of a novel model for ethical, translational research

Abstract Background Ex vivo perfusion techniques for human organs, in particular for the human liver, have been extensively studied for decades. Although ex vivo perfusion of human organs has been widely studied in the context of organ preservation and transplantation, it has also proven to be an invaluable tool in the development of novel models for translational pre-clinical research. Not only do these models allow more accurate study of human organ response to noxious external stimuli, but they also represent a far more ethical alternative to live animal experimentation.Although split-liver perfusion of the left or right hepatic lobe is well described in literature, ex vivo perfusion of isolated liver segments has not been previously attempted. A successful hepatic segmental perfusion model would provide a unique opportunity to study inflammation, response to infection and novel therapeutic approaches.The overall aim of this study was to establish an experimental ex vivo hepatic perfusion model on surgically resected human liver segments as a platform to evaluate and study organ preservation and function. The development of an ex vivo perfusion model of human liver segments would produce the ideal platform to study treatment effects without needing to sacrifice animals. Methods Patients were recruited as part of the TIMOLD (Tissue Models for Liver Disease) clinical trial (ClinicalTrials.gov Identifier: NCT05255042; 8/9/2021). Patients recruited were those aged eighteen or over undergoing elective liver resections at a single hepatobiliary unit. Nine human liver segments were retrieved following hemi-hepatectomy for colorectal liver metastases or hepatocellular carcinoma. A healthy segment was resected from the diseased specimen in theatre and a segmental hepatic artery and portal vein was cannulated immediately and flushed with ice cold heparinised preservation solution. Four segments were perfused with 600ml O negative expired red blood cells (HL-RBC) and five segments were perfused with 250ml Oxyglobin diluted with 250ml Volplex (HL-OXY). All segments were administered several drugs to provide metabolic support and optimise perfusion owing to their anticoagulant, antioxidant, and anti-inflammatory properties. Segments were perfused on a bespoke normothermic machine perfusion circuit for 4–6 hours. Perfusion parameters were monitored throughout perfusion and hourly hepatic venous blood gases were taken to monitor glucose and lactate levels. Hourly core biopsies were also taken for H&E staining and interpreted by a consultant histopathologist. Data is reported as the median (range) and statistical analysis has been performed using the Mann-Whitney U test on Graphpad Prism. Results HL-RBC (n=4) had a median pre-perfusion weight of 216 (146–1330) grams whilst HL-OXY (n=5) had a median weight of 269(128–367) grams (p>0.05). HL-RBC segments had a median warm ischaemic (WI) time of 76.5(68–81) minutes and a median cold ischaemic (CI) time of 97 (35–119) minutes. HL-OXY segments had a median WI time of 5 (3–80) minutes and a median CI time of 38 (28–63) minutes (p>0.05). Median portal venous resistance was lower for the HL-OXY group (0.076mmHg/ml/min) in comparison to the HL-RBC group (0.62mmHg/ml/min); p<0.05. There was no significant difference in hepatic arterial resistance between the two groups (HL-RBC 3 mmHg/ml/min; HL-OXY 2.38 mmHg/ml/min; p>0.05). HL-OXY had a lower median lactate of 4.54mmol/L in comparison to HL-RBC (14.7mmol/L) throughout perfusion (p<0.05). HL-OXY segments also had a lower median glucose of 5.9mmol/L compared to 9.65mmol/L for HL-RBC (p<0.05). 1/4 HL-RBC segments had normal histology after 6 hours of perfusion. 2/4 segments showed evidence of necrosis after 2 hours (one with established cirrhosis), and 1/4 segment demonstrated necrosis after 3 hours of perfusion. 4/5 HL-OXY segments demonstrated normal histology after 6 hours of perfusion. One segment, with known cirrhosis, demonstrated necrosis after two hours of perfusion. Conclusions We present here, for the first time, the development of a successful ex vivo isolated hepatic segmental perfusion model. We demonstrate, in the development of this model, that bovine haemoglobin glutamer-200 (Oxyglobin) is a superior oxygen carrier to expired O negative red blood cells in the ex vivo perfusion of isolated human hepatic segments. The HL-OXY group demonstrated a significantly lower portal venous resistance in comparison to HL-RBC, although there was no difference in arterial resistance. Furthermore, HL-OXY segments had lower median glucose and lactate levels during perfusion compared to HL-RBC segments. 4 of 5 segments perfused with Oxyglobin demonstrated viable hepatocytes on histopathological analysis after 6 hours of perfusion. The segment demonstrating early necrosis was one with established cirrhosis on pre-perfusion histology. We describe a protocol for the successful ex vivo perfusion of non-cirrhotic human hepatic segments. Human liver is routinely resected in tertiary hepatobiliary units and much of the specimen discarded. The paradigm presented here identifies a readily available ethical source of human liver with minimal warm ischaemia. This facilitates optimal conditions for translational research, is cost-effective and avoids animal experimentation.

The Safety and Efficacy of Hepatic Transarterial Embolization Using Microspheres and Microcoils in Patients with Symptomatic Polycystic Liver Disease.

Purpose: We investigated the long-term safety and efficacy of hepatic transarterial embolization (TAE) in patients with symptomatic polycystic liver disease (PLD). Materials and Methods: A total of 26 patients were included, mean age of 52.3 years (range: 33–78 years), undergoing 32 TAE procedures between January 2012 and December 2019 were included in this retrospective study. Distal embolization of the segmental hepatic artery was performed with 300–500 µm embolic microspheres associated with proximal embolization using microcoils. The primary endpoint was clinical efficacy, defined by an improvement in health-related quality of life using a modified Short Form-36 Health Survey and improvement in symptoms (digestive or respiratory symptoms and chronic abdominal pain), without invasive therapy during the follow-up period. Secondary endpoints were a decrease in total liver volume and treated liver volume and complications. Results: Hepatic embolization was performed successfully in 30 of 32 procedures with no major adverse events. Clinical efficacy was 73% (19/26). The mean reduction in hepatic volume was −12.6% at 3 months and −27.8% at the last follow-up 51 ± 15.2 months after TAE (range: 30–81 months; both ps < 0.01). The mean visual analog scale pain score was 5.4 ± 2.8 before TAE and decreased to 2.7 ± 1.9 after treatment. Three patients had minor adverse events, and one patient had an adverse event of moderate severity. Conclusion: Hepatic embolization using microspheres and microcoils is a safe and effective treatment for PLD that improves symptoms and reduces the volume of hepatic cysts.

A Motion Artifact Correction Algorithm for Cone-Beam CT in Patients with Hepatic Malignancies Treated with Transarterial Chemoembolization

PurposeTo evaluate the effect of a motion artifact correction algorithm (MACA) on cone-beam computed tomography (CT) during transarterial chemoembolization for hepatic malignancies. Materials and MethodsFrom June 2020 to March 2021, 42 patients with mild-to-severe motion artifacts detected using single cone-beam CT scans were evaluated retrospectively. The image quality of native and motion-corrected data was compared. The maximum intensity, sharpness, and full width at half maximum (FWHM) of 5 segmental hepatic arteries were quantitatively measured. The overall quality of maximum intensity projection (MIP) images, conspicuity of tumor-supplying arteries, and need for selective angiography to ascertain the vascular anatomy were qualitatively evaluated by multiple readers. Paired t and Wilcoxon signed rank tests were used to compare the parameters. ResultsThe mean maximum intensity and sharpness increased from 2,792.01 HU ± 451.36 to 3,148.40 HU ± 594.46 and from 0.31 ± 0.02/mm to 0.34 ± 0.02/mm, respectively, using the MACA (both P < .001). The MACA decreased the mean FWHM from 2.02 mm ± 0.27 to 1.78 mm ± 0.26 (P < .001). The overall quality of the MIP images and the conspicuity of the tumor-supplying artery were enhanced from 2.5 to 3.0 points and from 3.0 to 4.0 points, respectively (both P < .001). Selective angiography was expected to be omitted in 7 cases (16.7%, 7/42) after using the MACA. ConclusionsThe MACA significantly improved both quantitative and qualitative image quality of cone-beam CT in selected patients with motion artifacts during transarterial chemoembolization for hepatic malignancies.

Случай рецидива травматической гемобилии после селективной эмболизации сегментарной печеночной артерии

The article describes a rare case of recurrent hemobilia after previously performed selective embolizationof a segmental hepatic artery. A 33-year-old man underwent open (laparotomic) suturing of the injury dueto a rupture of segments VI-VII of the liver, but 3 weeks after the operation, the patient developed signs ofgastrointestinal bleeding. According to the results of ultrasound, duodenoscopy, MSCT and celiacography, afalse aneurysm of the segmental artery of the VII-VIII segments of the liver was revealed, in connection withwhich the embolization of the feeding artery was performed, and hemobilia was stopped. Two weeks afterembolization, a recurrence of hemobilia was noted; repeated celiacography revealed an arteriobiliary fistulathrough the wall of a false aneurysm. Selective catheterization of the artery of the right lobe of the liver wasperformed and embolization was performed - a complete shutdown of the target artery was achieved, however,there was a flow of contrast into the aneurysm through collaterals from the arteries of the left lobe of the liver,which required additional embolization of the artery of the left lobe of the liver. After the procedure, the signsof gastroduodenal bleeding stopped.

Anatomic Variations of the Hepatic Artery in 5625 Patients.

To analyze the origin and anatomic course of the hepatic arteries by using digital subtraction angiography (DSA) and multidetector CT in a large study sample. This retrospective study included 5625 patients who underwent liver CT and chemoembolization between January 2005 and December 2018 (mean age, 60 years ± 11 [range, 11-99 years]; 4464 males). The CT and DSA images were reviewed to evaluate the visceral arterial anatomy for variations in the celiac axis and hepatic arteries. Aberrant right hepatic arteries (aRHAs) and aberrant left hepatic arteries (aLHAs) were defined on the basis of their origin and anatomic course. Statistical analyses were performed to evaluate the association between aRHAs and aLHAs and the association between variations in the hepatic artery and celiac axis. Right hepatic arteries were categorized as being aRHAs (if originating from the proximal to middle common hepatic artery, gastroduodenal artery, superior mesenteric artery [SMA], celiac axis, aorta, splenic artery, or left gastric artery [LGA]) or as being aLHAs (if arising from the LGA, celiac axis, aorta, or SMA). The prevalence of aRHAs (15.63%; 879 of 5625) and the prevalence aLHAs (16.32%; 918 of 5625) were similar. Patients with an aRHA were more likely to have an aLHA than those without an aRHA (29.01% vs 13.97%; P < .001), and patients with an aLHA were more likely to have an aRHA than those without an aLHA (27.78% vs 13.26%; P < .001). There was no association between the hepatic arterial variations and celiac axis variations. A hypothetical anatomic model summarizing the observed variations was created. A comprehensive list of hepatic arterial variations and a three-dimensional hypothetical model for the observed variations were described.Keywords: CT, Angiography, Liver, Anatomy, Arteries© RSNA, 2021 Supplemental material is available for this article. See also commentary by Sutphin and Kalva in this issue.

Abstract No. 544 Evaluation of software predicting selective liver perfusion for embolization planning

To evaluate the accuracy of a liver embolization planning software (Liver ASSIST V.I. with Virtual Parenchymography prototype, GE Healthcare, Chicago, IL) to automatically predict perfused liver volume from any virtual selective injection point on a proximally enhanced planning cone-beam CT (CBCT). Planning CBCTs acquired proximally and associated selective CBCT couples from patients undergoing liver embolization in two centers were included in this retrospective study. Inclusion criteria were as follows: perfused liver parenchyma volume on the selective CBCT > 100cc and with adequate enhancement to allow for manual contouring. Perfused liver parenchyma was contoured manually on all selective CBCTs, defining the ground truth volume. The Virtual Perfused Volume (VPV) was obtained with the software by selecting the virtual injection point on the proximal CBCT matching the actual injection point of the associated selective CBCT. Software accuracy was evaluated by comparing the VPV to the ground truth volume after registering the proximal and selective CBCTs based on liver borders. Software accuracy is reported as relative volumetric error (%) and Dice spatial overlap coefficient (%). Results are expressed as mean [interquartile range]. 32 CBCT couples were included in 18 patients. Proximal CBCTs were acquired from the common (52%), right (18%), left (9%) or segmental (21%) hepatic arteries. Selective CBCTs were acquired from the right (12%), left (19%), and third or greater order right (65%) or left (4%) hepatic artery, with an average perfused liver parenchyma volume of 512cc [192, 699]. Software was successful in automatically computing VPV in all cases. Relative volumetric error and Dice coefficient were 15% [5%-20%] and 77% [73%-84%] in the entire cohort. In the sub-analysis on the 27 couples with proximal CBCTs acquired from the common, right or left hepatic artery, relative volumetric error and Dice coefficient were 12% [4%-18%] and 78% [74%-84%], with no significant difference between centers (P = .31 and .13). Preliminary evaluation of selective perfused liver volume prediction from proximal CBCTs showed acceptable accuracy. This software could help identify optimal embolization strategy based on a single proximal CBCT, avoiding multiple selective acquisitions for liver embolization planning. Further studies are warranted to demonstrate its benefits for radioembolization CBCT-based volumetry, reducing the need for distal vessel catheterization during mapping, and streamlining dosimetry workflow.

Hepatic Artery Embolization for Postoperative Hemorrhage: Importance of Arterial Collateral Vessels and Portal Venous Impairment

PurposeTo investigate the association between hepatic ischemic complications and hepatic artery (HA) collateral vessels and portal venous (PV) impairment after HA embolization for postoperative hemorrhage. Materials and MethodsFrom October 2003 to November 2019, 42 patients underwent HA embolization for postoperative hemorrhage. HA collateral vessels were classified according to visualization after embolization (grade 1, none; grade 2, 1–4 segmental HA; and grade 3, ≥4 segmental HA). Transhepatic portal vein stent placements were performed in the same session for 5 patients (11.9%) with poor HA collateral vessels (grade 1 or 2) and compromised PV flow (>70% stenosis). Hepatic ischemic complications were analyzed for relevance to HA collateral vessels and PV compromise. ResultsAfter HA embolization, HA flow was found to be preserved (grade 3) through intra- and/or extrahepatic collateral vessels in 23 patients (54.8%), and hepatic complications did not occur regardless of PV flow status (0%). Of the 19 patients (45.2%) with poor HA collateral vessels (grade 1 or 2), segmental hepatic infarction occurred in 2 of 15 patients (13.3%) with preserved PV flow (10 naïve and 5 stented). The remaining 4 patients with poor HA collateral vessels and untreated compromised PV flow experienced multisegmental hepatic infarction (n = 3) or hepatic failure (n = 1) (100%) (P < .005). ConclusionsAfter HA embolization, preserved HA flow (≥4 segmental HA) lowered the risk of hepatic complications regardless of the PV flow. Based on these findings, transhepatic PV stent placement seems to be an effective intervention for the prevention of hepatic complications in cases of poor HA collateral vessels and compromised PV flow.

Percutaneous Implantation of a Microcatheter-Port System for Hepatic Arterial Infusion Chemotherapy of Unresectable Liver Tumors: Technical Feasibility, Functionality, and Complications.

To evaluate the feasibility and safety of percutaneously implanted arterial port catheter systems for hepatic arterial infusion of chemotherapy (HAI) in patients with unresectable liver malignancies. From October 2010 to August 2018, arterial port catheters for HAI were percutaneously implanted in 43 patients with unresectable liver malignancies. Three different catheter placement techniques were compared: a conventional end-hole catheter placed in the common hepatic artery (technique 1, n = 16), a side-hole catheter with the tip fixed in the gastroduodenal artery (technique 2, n = 18), and a long-tapered side-hole catheter with the tip inserted distally in a segmental hepatic artery (technique 3, n = 6). Catheter implantation was successful in 40 (93%) of the 43 patients. Complications related to catheter placement were observed in 10 (23%) patients; 5 (83%) of the 6 major complications were resolved, as well as all 4 minor complications. Catheter migration and occlusion occurred in 9 (22.5%) patients. Catheter migration was more frequent with technique 1 (n = 6) than with technique 2 (n = 1), although the difference was not significant (p = 0.066). Percutaneous arterial port catheter implantation for HAI is highly feasible and carries a low risk of complications.

First In Vivo Test of Thermoembolization: Turning Tissue Against Itself Using Transcatheter Chemistry in a Porcine Model.

Embolotherapies are commonly used for management of primary liver cancer. Explant studies of treated livers, however, reveal an untreated tumor in a high fraction of cases. To improve on this, we propose a new concept referred to as thermoembolization. In this technique, the embolic material reacts in local tissues. Highly localized heat energy is released simultaneously with the generation of acid in the target vascular bed. Combined with ischemia, this should provide a multiplexed attack. We report herein our initial results testing the feasibility of this method in vivo. Institutional approval was obtained, and three outbred swine were treated in a segmental hepatic artery branch (right or left medial lobe) with thermoembolic material (100, 400, or 500µL). Solutions (2 or 4mol/L) of an acid chloride were made using ethiodized oil as the vehicle. Animals were housed overnight, scanned by CT, and euthanized. Necropsy samples of treated tissue were obtained for histologic analysis. All animals survived the procedure. Vascular stasis occurred rapidly in all cases despite the small volumes used. The lower concentration (2mol/L) penetrated more distally than the 4mol/L solution. At CT the following day, vascular casts of ethiodized oil were observed, indicating recanalization had not occurred. Histology specimens demonstrated coagulative necrosis centered on the vessel lumen extending for several hundred microns with a peripheral inflammatory infiltrate. Thermoembolization is a new technique for embolization with initial promise. However, results indicate much work must be done to optimize the technique.

Pressure-Directed Embolization of Hepatic Arteries in a Porcine Model Using a Temporary Occlusion Balloon Microcatheter: Proof of Concept

The purpose of this project was to test the hypothesis that temporary hepatic artery balloon occlusion would favorably alter the distribution of particle emboli within the targeted and nontargeted downstream vascular compartments. Five Yorkshire pigs underwent transfemoral placement of balloon microcatheters into selected segmental hepatic arteries. A collection catheter was surgically introduced into a downstream hepatic artery branch. Blood pressures at the femoral artery sheath and the collection catheter were obtained with the microcatheter balloon deflated and inflated. Identical quantities of calibrated 250- and 400-µm microspheres were injected via the balloon microcatheter when inflated, then deflated. Each animal underwent up to four paired microsphere embolizations. Microspheres collected from the intrahepatic collection catheter were counted manually by light microscopy. Inflation of the balloon microcatheter in the segmental hepatic artery resulted in a consistent and significant decrease in blood pressure (mean: 30mmHg; range 23-43mmHg; p<0.05) in the downstream vascular compartment. The number of microspheres selectively delivered to the targeted intrahepatic collection catheter was significantly greater when the balloon microcatheter was inflated rather than deflated in all 20 paired embolic deliveries (by 2.4-fold, mean; p=0.0002), despite delivery of the same total number of microspheres. Balloon occlusion significantly reduces blood pressure in the downstream vascular compartment, resulting in increased delivery of emboli to a targeted intrahepatic arterial collection catheter relative to other portions of the embolized vascular compartment, likely due to blood flowing into this compartment from neighboring hepatic and extrahepatic arteries.

Superselective intra-arterial hepatic injection of indocyanine green (ICG) for fluorescence image-guided segmental positive staining: experimental proof of the concept.

Intraoperative liver segmentation can be obtained by means of percutaneous intra-portal injection of a fluorophore and illumination with a near-infrared light source. However, the percutaneous approach is challenging in the minimally invasive setting. We aimed to evaluate the feasibility of fluorescence liver segmentation by superselective intra-hepatic arterial injection of indocyanine green (ICG). Eight pigs (mean weight: 26.01±5.21kg) were involved. Procedures were performed in a hybrid experimental operative suite equipped with the Artis Zeego®, multiaxis robotic angiography system. A pneumoperitoneum was established and four laparoscopic ports were introduced. The celiac trunk was catheterized, and a microcatheter was advanced into different segmental hepatic artery branches. A near-infrared laparoscope (D-Light P, Karl Storz) was used to detect the fluorescent signal. To assess the correspondence between arterial-based fluorescence demarcation and liver volume, metallic markers were placed along the fluorescent border, followed by a 3D CT-scanning, after injecting intra-arterial radiological contrast (n=3). To assess the correspondence between arterial and portal supplies, percutaneous intra-portal angiography and intra-arterial angiography were performed simultaneously (n=1). Bright fluorescence signal enhancing the demarcation of target segments was obtained from 0.1mg/mL, in matter of seconds. Correspondence between the volume of hepatic segments and arterial territories was confirmed by CT angiography. Higher background fluorescence noise was found after positive staining by intra-portal ICG injection, due to parenchymal accumulation and porto-systemic shunting. Intra-hepatic arterial ICG injection, rapidly highlights hepatic target segment borders, with a better signal-to-background ratio as compared to portal vein injection, in the experimental setting.

Assessment of the parenchymal blood volume by C-arm computed tomography for radioembolization dosimetry

PurposeAim of the study was to evaluate the impact of parenchymal blood volume (PBV) C-arm CT in transarterial radioembolization (TARE) planning procedure regarding the appropriateness of segmental blood supply from selective catheter positions defined by angiographic images compared to PBV mapsto determine the influence of changed target volumes on dose calculation. Material and methodsA total of 22 consecutive patients (median age, 62 years) underwent a TARE planning procedure were included in this retrospective study. Selective angiograms and selective PBV C-arm CT (right and left liver lobe) were evaluated in a blinded fashion, regarding segmental hepatic artery variants. Volumetry of target volume and dosimetry of glass and resin microspheres were performed. ResultsClassification of segment IV and segment I to the corresponding target vascular bed supply was correct in 91.0% (20/22) and 86.4% (19/22) for angiography and C-arm CT, respectively. Except one case, all other liver segments were classified properly to the left and right hepatic arterial supply. Based on the mismatch of the angiographic and the C-arm CT approach, changes of target volume were evident in 27.3% of patients, resulting in a mean mismatch volume of 90±54ml (range, 51–198ml) and a percentage of dose differences of 14.2±11.8% and 12.6±10.6% for the right and 12.5±8.5% and 11.1±7.8% for the left liver lobe in glass and resin microspheres, respectively. ConclusionThe C-arm CT approach is superior to the angiographic determination of vascular supply of specific liver segments for dosimetry before radioembolization. Especially for unexperienced interventional radiologists or for a complex anatomy, C-arm CT improves individualized dosimetry concepts.

Balloon-occluded arterial stump pressure before balloon-occluded transarterial chemoembolization

Objective To evaluate balloon-occluded arterial stump pressure (BOASP), which is responsible for effective balloon-occluded transarterial chemoembolization (B-TACE), at each hepatic arterial level before B-TACE using a 1.8-French tip microballoon catheter for unresectable hepatocellular carcinoma (HCC). Material and methods The BOASP at various embolization portions was retrospectively investigated. “Selective” and “non-targeted” BOASP was defined as the BOASP at the subsegmental or segmental artery and the lobar artery, respectively. Results The measurement of the BOASP was carried out in 87 arteries in 47 patients. BOASP > 64 mmHg was revealed in the caudate lobe artery (A1) and the left medial segmental (A4), right anterior superior segmental (A8), anterior segmental, right and left hepatic arteries. Significant difference was noted in the incidence of BOASP above 64 mmHg between “non-targeted” and “selective” BOASP (p = 0.01). “Non-targeted” BOASP was significantly greater than “selective” BOASP (p = 0.0147). In addition, the BOASP in A1, 4, 8 and the anterior segmental arteries were significantly greater than in the other subsegmental and segmental arteries (p = 0.0007). Conclusion “Non-targeted” B-TACE should be avoided to perform effective B-TACE and “selective” B-TACE at A1, 4, 8 and the anterior segmental arteries may become less effective than at the other segmental or subsegmental arteries.

Cone-Beam CT Hepatic Arteriography in Chemoembolization for Hepatocellular Carcinoma: Angiographic Image Quality and Its Determining Factors

PurposeTo analyze image quality and the factors that determine it for cone-beam computed tomography (CT) hepatic arteriography in chemoembolization for hepatocellular carcinoma (HCC). Materials and MethodsFrom September 2009–December 2010, 399 consecutive patients referred for chemoembolization of HCC were scheduled for cone-beam CT scan. There were 12 patients (3%) excluded because of difficulty with breath-hold. Of the 387 patients who underwent cone-beam CT hepatic arteriography, 100 patients were ultimately included in the study according to inclusion criteria. Maximum intensity projection images were scored for image quality of each segmental hepatic artery. Potential determining factors for image quality were diaphragmatic motion, portal vein enhancement, and hepatic artery-to-parenchyma enhancement ratio. The flow rate of contrast media, x-ray delay, and location of the catheter tip were also evaluated. ResultsIt was possible to trace at least subsegmental hepatic arteries in 625 of 700 segments (89.3%) on cone-beam CT hepatic arteriography. Diaphragmatic motion, prominent portal vein enhancement, and low hepatic artery-to-parenchyma enhancement ratio worsened image quality (P < .001, P = .022, and P = .017). Owing to cardiac motion artifacts, image quality of the left lateral segments (S2 and S3) was poorer compared with the remaining hepatic segments (S4–S8). ConclusionsIn most cases, the quality of cone-beam CT hepatic arteriography images was good enough to trace subsegmental hepatic arteries at a minimum. Respiratory and cardiac motion, portal vein enhancement, and hepatic artery-to-parenchyma enhancement ratio significantly affected the image quality of cone-beam CT hepatic arteriography.

Abstract No. 335 - Initial clinical experience with a novel microcatheter-deliverable vascular plug

PurposeTo discuss and evaluate the efficacy of the MVP™ Micro Vascular Plug system, a self-expanding vessel occlusion device, in peripheral and neurovascular applications.Materials and MethodsA retrospective review was conducted of six cases from August to September 2013, two cases of neurotrauma and four cases of hepatic arterial mapping prior to Y90 radioembolization. All six cases utilized the MVP-3 Micro Vascular Plug system for embolization, a self-expanding occlusion device comprised of nitinol and a partial PTFE cover intended for vessels ranging from 1.5 to 3.0 mm in diameter deliverable through a 0.021 inch inner diameter microcatheter.ResultsPrompt and complete occlusion of the target vessels was observed in all six cases without a necessity for a secondary embolization agent. Target vessels included vertebral, lingual, segmental hepatic, gastroduodenal, and supraduodenal arteries. Two vascular plugs were required in one of the neurointerventions given the complexity of the traumatic injury. No significant migration of the plugs was observed.ConclusionThe MVP™ Micro Vascular Plug system, currently available in the United States in a 3-mm system and deliverable through a 0.021 inch microcatheter, was effective in prompt occlusion of target vessels in both peripheral and neurovascular applications. PurposeTo discuss and evaluate the efficacy of the MVP™ Micro Vascular Plug system, a self-expanding vessel occlusion device, in peripheral and neurovascular applications. To discuss and evaluate the efficacy of the MVP™ Micro Vascular Plug system, a self-expanding vessel occlusion device, in peripheral and neurovascular applications. Materials and MethodsA retrospective review was conducted of six cases from August to September 2013, two cases of neurotrauma and four cases of hepatic arterial mapping prior to Y90 radioembolization. All six cases utilized the MVP-3 Micro Vascular Plug system for embolization, a self-expanding occlusion device comprised of nitinol and a partial PTFE cover intended for vessels ranging from 1.5 to 3.0 mm in diameter deliverable through a 0.021 inch inner diameter microcatheter. A retrospective review was conducted of six cases from August to September 2013, two cases of neurotrauma and four cases of hepatic arterial mapping prior to Y90 radioembolization. All six cases utilized the MVP-3 Micro Vascular Plug system for embolization, a self-expanding occlusion device comprised of nitinol and a partial PTFE cover intended for vessels ranging from 1.5 to 3.0 mm in diameter deliverable through a 0.021 inch inner diameter microcatheter. ResultsPrompt and complete occlusion of the target vessels was observed in all six cases without a necessity for a secondary embolization agent. Target vessels included vertebral, lingual, segmental hepatic, gastroduodenal, and supraduodenal arteries. Two vascular plugs were required in one of the neurointerventions given the complexity of the traumatic injury. No significant migration of the plugs was observed. Prompt and complete occlusion of the target vessels was observed in all six cases without a necessity for a secondary embolization agent. Target vessels included vertebral, lingual, segmental hepatic, gastroduodenal, and supraduodenal arteries. Two vascular plugs were required in one of the neurointerventions given the complexity of the traumatic injury. No significant migration of the plugs was observed. ConclusionThe MVP™ Micro Vascular Plug system, currently available in the United States in a 3-mm system and deliverable through a 0.021 inch microcatheter, was effective in prompt occlusion of target vessels in both peripheral and neurovascular applications. The MVP™ Micro Vascular Plug system, currently available in the United States in a 3-mm system and deliverable through a 0.021 inch microcatheter, was effective in prompt occlusion of target vessels in both peripheral and neurovascular applications.

8:16 AM Abstract No. 130 - Hepatotoxicity and mortality following transarterial chemoembolization with doxorubicin-eluting beads in patients with hepatocellular carcinoma and marginal hepatic reserve

Purpose To determine incidence and risk factors of irreversible hepatotoxicity after transarterial chemoembolization (TACE) with doxorubicin-eluting beads (DEB) for hepatocellular carcinoma (HCC) in a patient population with high prevalence of hepatic dysfunction. Materials and Methods Records of 48 consecutive patients with HCC who underwent 76 DEB-TACE procedures from 2011-2012 were retrospectively reviewed. Forty-seven (60.3%) and 26 (33.3%) of the procedures were performed in patients with total bilirubin of >2mg/dl and >3mg/dl respectively. Mean Model for End-Stage Liver Disease (MELD) score prior to TACE was 12.7 (median 13, standard deviation 4.0). Portal vein thrombus, hepatofugal flow, or transjugular intrahepatic portosystemic shunt (TIPS) was present prior to 17 procedures (21.8%). Thirty procedures (38.5%) were performed in patients with ascites. TACE was delivered to a segmental or subsegmental hepatic artery (50 procedures; 64.1%), two segmental hepatic arteries (23; 29.5%), or three segmental arteries (3; 3.8%). Hepatotoxicity was defined as new or worsening ascites or NCI Common Terminology Criteria for Adverse Events grade 3 or 4 toxicity of bilirubin, AST, ALT, creatinine or INR. Rates for death or urgent liver transplantation within 6 weeks of DEB TACE and irreversible hepatotoxicity were determined. Results Reversible hepatotoxicity developed after 13 procedures (16.7%) in 10 patients (20.8%). Irreversible hepatotoxicity developed after 11 procedures (14.1%) in 11 patients (22.9%). One patient required an urgent liver transplant in the setting of irreversible hepatotoxicity within 6 weeks of DEB-TACE. No patient died within 6 weeks of DEB-TACE. Conclusion DEB-TACE can be performed safely in patients with baseline hepatic dysfunction.

Radioembolization of Hepatic Tumors: Flow Redistribution After the Occlusion of Intrahepatic Arteries

Radioembolization using 90yttrium is an emerging therapy option for unresectable liver malignancies. In order to reduce the number of yttrium injections, endovascular occlusion of a segmental hepatic artery has been proposed. The aim of this study was to assess whether sufficient vascular redistribution of the occluded liver segments through intrahepatic collaterals can be observed. 27 patients with hepatocellular carcinoma (n = 16) or hepatic metastases (n = 11) were studied. Hepatic angiography was performed on average 16 days prior to radioembolization. The segment II/III artery (n = 9) or the segment IV artery (n = 18) was occluded using coils. Technectium-99m-labeled macroaggregated albumin (99mTc-MAA) was injected into the right and the remaining part of the left hepatic artery in order to identify any hepatic volume not included in the perfused area. Patients underwent a SPECT/CT on average 1 h after the 99mTc-MAA injection. Two radiologists evaluated the SPECT/CT scans regarding the presence of non-perfused hepatic segments. Furthermore, hepatic perfusion was assessed by digital subtraction angiography (DSA) on the day of radioembolization. In 16/27 patients (59%) a perfusion of the occluded liver segment was visible on the SPECT/CT scan. In 8/11 patients without flow redistribution at the time of the SPECT/CT, perfusion of the occluded segment through hepatic collaterals was observed during angiography prior to radioembolization. Hence, flow redistribution was eventually found in 24/27 patients (89%). Flow redistribution after the occlusion of intrahepatic arteries prior to radioembolization can be successfully induced in the majority of patients with anatomical variants of the hepatic arteries.

Previous Chemoembolization Response after Transcatheter Arterial Chemoembolization (TACE) Can Predict the Anti-Tumor Effect of Subsequent TACE with Miriplatin in Patients with Recurrent Hepatocellular Carcinoma

Aim: The purpose of this retrospective study was to evaluate the efficacy and safety of transcatheter arterial chemoembolization (TACE) with miriplatin in patients with unresectable hepatocellular carcinoma (HCC). Methods: From 2007 to 2010, 122 consecutive patients with unresectable HCC were treated by TACE with miriplatin-lipiodol suspension in our institute. Twenty-two patients (18%) had a solitary nodule and 100 patients (82%) had multiple nodules. Ninety-eight patients (80%) had a history of TACE. Results: Thirty-five of the 122 treated patients (29%) showed complete response (CR). And no serious complications were observed. Patients who had shown CR after previous TACE (pre-CR) were significantly more likely to show CR in the current study compared with patients who had shown less successful responses after previous TACE (56 vs. 20%, p = 0.003). Multivariate analysis revealed that response after previous TACE (pre-CR, risk ratio: 4.76; p = 0.035), tumor multiplicity (solitary, risk ratio: 9.69; p = 0.003), and injection artery (peripheral to segmental hepatic artery, risk ratio: 5.28;p = 0.040) were significant independent predictors associated with CR after TACE using miriplatin. Conclusion: In repetition of TACE treatment, switching the TACE agent from epirubicin or cisplatin to miriplatin offered a favorable treatment effect, especially in patients who had shown a CR after previous TACE.