Contralateral Hypertrophy Post Yttrium-90 Transarterial Radioembolization in Patients With Hepatocellular Carcinoma and Portal Vein Tumor Thrombus.

Objectives Contralateral hypertrophy of non-irradiated liver following Yttrium-90 (90Y) transarterial radioembolization (TARE) is increasingly recognized as an option to facilitate curative surgical resection in patients that would otherwise not be surgical candidates due to a small future liver remnant (FLR). This study aimed to investigate the correlation between patient features and liver hypertrophy and identify potential predictors for liver growth in patients with hepatocellular carcinoma (HCC) and portal vein tumor thrombus (PVTT) undergoing TARE. Methodology Twenty-three patients with HCC and PVTT were included. Contralateral liver hypertrophy was assessed at six months posttreatment based on CT or MRI imaging. Thirteen patient features were selected for statistical and prediction analysis. Univariate Spearman correlation and analysis of variance (ANOVA) tests were performed. Subsequently, four feature-selection methods based on multivariate analysis were used to improve model generalization performance. The selected features were applied to train linear regression models, with fivefold cross-validation to assess the performance of the predicted models. Results The ratio of disease-free target liver volume to spared liver volume and total liver volume showed the highest correlations with contralateral hypertrophy (P-values = 0.03 and 0.05, respectively). In three out of four feature-selection methods, the feature of disease-free target liver volume to total liver volume ratio was selected, having positive correlations with the outcome and suggesting that more hypertrophy may be expected when more volume of disease-free liver is irradiated. Conclusions Contralateral hypertrophy post-90Y TARE can be an option for facilitating surgical resection in patients with otherwise small FLR.

The Aortic Team Model and Collaborative Decision Pathways for the Management of Complex Aortic Disease: Clinical Practice Update From the Canadian Cardiovascular Society/Canadian Society of Cardiac Surgeons/Canadian Society for Vascular Surgery/Canadian Association for Interventional Radiology.

Disease of the aortic arch, descending thoracic, or thoracoabdominal aorta necessitates dedicated expertise across medical, endovascular, and surgical specialties. Cardiologists, cardiac surgeons, vascular surgeons, interventional radiologists, and others have expertise and skills that aid in the management of patients with complex aortic disease. No specialty is uniformly expert in all aspects of required care. Because of this dispersion of expertise across specialties, an aortic team model approach to decision-making and treatment is advocated. A nonhierarchical partnership across specialties within an interdisciplinary aortic clinic ensures that all treatment options are considered and promotes shared decision-making between the patient and all aortic experts. Furthermore, regionalization of care for aortic disease of increased complexity assures that the breadth of treatment options is available and that favourable volume-outcome ratios for high-risk procedures are maintained. An awareness of best practice care pathways for patient referrals for preventative management, acute care scenarios, chronic care scenarios, and pregnancy might facilitate a more organized management schema for aortic disease across Canada and improve lifelong surveillance initiatives.

Hepatic Hilar Nerve Block for Adjunctive Analgesia during Percutaneous Thermal Ablation of Hepatic Tumors: A Retrospective Analysis.

PURPOSE: To determine whether hepatic hilar nerve block techniques reduce analgesic and sedation requirements during percutaneous image-guided thermal ablation of hepatic tumors. MATERIALS AND METHODS: A single-center retrospective cohort analysis was performed of 177 patients (median age, 67 years; range, 33-86 years) who underwent percutaneous image-guided thermal ablation of liver tumors. All patients were treated utilizing local anesthetic and moderate sedation between November 2018 and November 2021 at a tertiary level hospital, with or without the administration of a hepatic hilar nerve block. Univariable and multivariable linear regression analyses were performed to determine the relationship between the administration of the hilar nerve block and fentanyl and midazolam dosages. RESULTS: A total of 114 (64%) patients received a hilar nerve block in addition to procedural sedation, and 63 (36%) patients received procedural sedation alone. There were no significant differences in the baseline demographic and tumor characteristics between the cohorts. The procedure duration was longer in the hilar block cohort than in the unblocked cohort (median, 95 vs 82 minutes; P = .0012). The technical success rate (98% in both the cohorts, P = .93) and adverse event rate (11% vs 3%, P = .14) were not significantly different between the cohorts. After adjusting for patient and tumor characteristics, ablation modality, and procedure and ablation durations, hilar nerve blocks were associated with lower fentanyl (-18.4%, P = .0045) and midazolam (-22.7%, P = .0007) dosages. CONCLUSIONS: Hepatic hilar nerve blocks significantly decrease the fentanyl and midazolam requirements during thermal ablation of hepatic tumors, without a significant change in the technical success or adverse event rates.

Safety and Efficacy of a Truncated Deflation Algorithm for Distal Transradial Access.

PURPOSE: To assess safety and efficacy of a modified rapid hemostasis protocol for distal transradial access (TRA). MATERIALS AND METHODS: A single-center retrospective study of patients undergoing percutaneous image-guided procedures from a distal TRA with rapid deflation hemostasis protocol was performed. Between March 2017 and August 2019, 593 procedures in 434 patients were performed. Mean patient age was 63.5 y (range, 18-94 y). RESULTS: The most common procedures were transarterial chemoembolization (218; 36.8%), abdominal and pelvic embolization (116; 19.6%), yttrium-90 mapping (115; 19.4%), yttrium-90 administration (84; 14.2%), and diagnostic angiography (44; 7.4%). Mean (range) values for clotting parameters were international normalized ratio 1.2 (0.9-3.2), partial thromboplastin time 33.5 s (26-44 s), and platelets 23.4 × 109/L (37-552 × 109/L). A hematoma developed in 7 (1.2%) patients. No radial artery occlusions were encountered during follow-up. Nursing intensity was defined as the number of minutes after the procedure required for assessing and managing the access site for bleeding. The mean nursing intensity was 25.1 min (range, 25-40 min). CONCLUSIONS: The rapid deflation hemostasis protocol for distal TRA at the anatomical snuffbox was feasible and safe. No significant difference or association was found between hematoma formation and clotting parameters after the procedure or type of vascular access equipment used.

Left Distal Transradial Access (ldTRA): A Comparative Assessment of Conventional and Distal Radial Artery Size.

PURPOSE: To assess left radial artery size, technical feasibility and safety of ldTRA in the anatomical snuffbox for percutaneous image-guided procedures. MATERIALS AND METHODS: A retrospective single-center study was performed from November 2016 to June 2018 on all patients undergoing ldTRA for interventional radiology procedures. RESULTS: A total of 287 patients (91 female and 196 male), aged 18-94 years (mean age 64 years), were included. 389 procedures were performed which included hepatic chemoembolization (n = 161), selective internal radiation therapy Y-90 mapping (n = 74), selective internal radiation therapy Y-90 administration (n = 48), diagnostic angiography (n = 34), mesenteric and pelvic embolization (n = 59), stent insertion (n = 8) and miscellaneous (n = 5). Mean sonographic measurement of the left radial artery size at the conventional site at the wrist was 2.55 mm (range 1.4-3.3 mm) and 2.34 mm (range 1.4-3.2 mm) at the anatomical snuffbox (p < 0.001). Technical success rate was 100%, a single small hematoma occurred in the first patient (0.3%). 74.2% of patients had follow-up for radial artery patency (mean 46 days, range 0-66 days), which did not reveal radial artery occlusions or pseudoaneurysm formation. CONCLUSION: The left distal radial artery in the anatomical snuffbox is smaller in comparison with the conventional access site at the wrist. The difference however is small and does not require intentional downsizing of vascular access equipment to facilitate utilization of ldTRA. Assessment of the vessel size is imperative for appropriate equipment selection and optimizing procedural success. This study supports that ldTRA is technically feasible and safe.

Ablative Transarterial Radioembolization Improves Survival in Patients with HCC and Portal Vein Tumor Thrombus.

PURPOSE: Patients with hepatocellular carcinoma and portal vein tumor thrombus have a poor prognosis and limited therapeutic options. We sought to compare survival, tolerability, and safety in such patients treated with conventional yttrium-90 transarterial radioembolization dosimetric techniques or ablative transarterial radioembolization. MATERIALS AND METHODS: This retrospective, single-center cohort study included patients with hepatocellular carcinoma and right, left, and/or main portal vein tumor thrombus, preserved liver function (Child-Pugh class ≤ B7), and good performance status (Eastern Cooperative Oncology Group score ≤ 1) treated with yttrium-90 microspheres from 2011 to 2018 with ablative intent transarterial radioembolization (A-TARE), or conventional technique (cTARE). Statistical models were used to compare overall survival, post-treatment survival, toxicities, and prognosticators of response. RESULTS: Fifty-seven patients were included (21 [36.8%] ablative and 36 [63.2%] conventional intent). Median overall survival was 15.7 months. Compared to conventional treatment, ablative radioembolization was associated with longer median overall survival (45.3 vs 18.2 months; P = 0.003), longer post-treatment survival (19.1 vs 4.9 months; P = 0.005), a 70% lower risk of death (hazard ratio 0.30; 95% confidence interval, 0.13-0.70; P = 0.005), and improved 4-year survival (53.9% vs 11.2%). Overall survival did not differ significantly between treatment with resin and glass microspheres (27.5 vs 22.2 months; P = 0.62). Acceptable hepatic toxicities were observed after yttrium-90 administration, without statistical differences between the groups. CONCLUSION: In patients with advanced hepatocellular carcinoma and portal vein tumor thrombus, A-TARE is associated with longer survival than cTARE. Neither modality is associated with deleterious effects on liver function.

Transapical Coil Embolization of a Postsurgical Ascending Thoracic Aortic Pseudoaneurysm.

Ascending aortic pseudoaneurysms are a rare but potentially life-threatening complication of aortic root or cardiac surgery. Surgical repair is established as first-line treatment; however, patient comorbidities, technical considerations, and anatomic limitations often preclude patients from repeat surgery, thus necessitating alternative approaches. Here, we present a case of coil embolization of an ascending aortic pseudoaneurysm via a transapical approach in a particularly complex scenario where percutaneous and peripheral access was technically unfeasible.

Radical Radial: Pearls and Pitfalls in Transradial Yttrium-90 Liver-Directed Therapy.

The frequency of transradial access in interventional radiology has been steadily increasing, including for yttrium-90 (Y-90) selective internal radiation therapy to treat hepatic malignancies. The aim of this article is to detail an optimized approach to transradial Y-90 (TRY-90), showing it to be a safe and feasible first-line approach to hepatic selective internal radiation therapy. Salient preprocedural considerations to enable appropriate patient selection for TRY-90 are discussed and a detailed equipment list is provided. The article will describe our approach to TRY-90 in addition to a discussion around technical pearls and pitfalls.

Prospective Study on Total Fluoroscopic Time in Patients Undergoing Uterine Artery Embolization: Comparing Transradial and Transfemoral Approaches.

PURPOSE: Comparing total fluoroscopy time (FT) to perform uterine artery embolization (UAE) with transradial approach (TRA) versus transfemoral approach (TFA). Our hypothesis was that there would be no significant procedural time penalty incurred, despite the learning curve associated with adopting a new approach. MATERIALS AND METHODS: A cohort study was undertaken including 66 consecutive patients undergoing UAE with either TRA/TFA between January and September 2015. Total FT was recorded prospectively for each procedure, and data subsequently analyzed retrospectively. Each operator had at least 2 years of experience as an interventional radiologist having performed at least 200 TFA UAEs. All operators had recently incorporated TRA into their practice. RESULTS: A total of 39 TFA and 27 TRA cases were included in the study; mean age for TFA group was 44.4 years (± 4.9) and for TRA group was 45.1 years (± 4.9) (p = 0.59). Mean FTs were comparable between the two groups (p = 0.86) despite a learning curve associated with TRA: The mean total FT with TFA was 20.36 min (± 9.48) compared to TRA 20.12 min (± 7.67). CONCLUSIONS: FTs for TRA UAE were comparable to TFA UAE, even though TRA had been recently adopted as a new approach. Despite the learning curve associated with developing a novel technique, operators should not expect the efficiency of their service to be significantly compromised. Introducing this safe and effective method of vascular access should therefore be considered.

Intraprocedural Parenchymal Blood Volume Is a Predictor of Treatment Response for Chemoembolization in Hepatocellular Carcinoma: Results of a Prospective Study.

PURPOSE: To evaluate cone-beam parenchymal blood volume (PBV) before and after embolization as a predictor of radiographic response to transarterial chemoembolization in unresectable hepatocellular carcinoma (HCC). MATERIALS AND METHODS: A phase IIa prospective clinical trial was conducted in patients with HCCs > 1.5 cm undergoing chemoembolization; 52 tumors in 40 patients with Barcelona Clinic Liver Criteria stage B disease met inclusion criteria. Pre- and postembolization PBV analysis was performed with a semiquantitative best-fit methodology for index tumors, with a predefined primary endpoint of radiographic response at 3 months. Analyses were conducted with Wilcoxon signed-rank tests and one-way analysis of variance on ranks. RESULTS: Mean tumoral PBV measurements before and after embolization were 170 mL/1,000 mL ± 120 and 0 mL/100 mL ± 130, respectively. Per modified Response Evaluation Criteria In Solid Tumors, 25 tumors (48%) exhibited complete response (CR), 13 (25%) partial response (PR), 3 (6%) stable disease (SD), and 11 (21%) progressive disease (PD). Statistically significant changes in median PBV (ΔPBV) were identified in the CR (P = .001) and PR (P = .003) groups, with no significant difference observed in SD (P = .30) and PD groups (P = .06). A statistically significant correlation between ΔPBV and tumor response was established by one-way analysis of variance on ranks (P = .036; CR, 200 mL/100 mL ± 99; PR, 240 mL/100 mL ± 370; SD, 64 mL/100 mL ± 99; PD, 88 mL/100 mL ± 129). CONCLUSIONS: Intraprocedural PBV can be used as a predictor of response in index HCC tumors of > 1.5 cm.

Transradial Access for Interventional Radiology: Single-Centre Procedural and Clinical Outcome Analysis.

PURPOSE: The study sought to describe a single centre's technical approach to transradial intervention and report on clinical outcomes and safety. METHODS: A total of 749 transradial access (TRA) procedures were performed at a single hospital in 562 patients (174 women and 388 men). Procedures included 445 bland embolizations or chemoembolizations of the liver, 88 uterine artery embolizations, and 148 procedures for Selective Internal Radiation Therapy (Y90), which included mapping and administration. The mean age of the patients was 62 years (range 27-96 years). RESULTS: Four cases (0.5%) required crossover to transfemoral (tortuous anatomy, inability to secure a stable position for embolization, vessel spasm and base catheter not being of a sufficient length). A single asymptomatic, short-segment radial artery occlusion occurred (0.3%), 3 patients (0.4%) developed small hematomas postprocedurally, and 2 patients (0.7%) had transient neurological pain, which was resolved within a week without treatment. It was found that 98% of patients who had a previous femoral access procedure would choose radial access for subsequent procedures. CONCLUSIONS: Transradial access is a safe, effective technique, with a learning curve; however, this procedure has the potential to significantly improve departmental workflow and cost savings for the department and patient experience.

Hepatocellular Carcinoma Post Embolotherapy: Imaging Appearances and Pitfalls on Computed Tomography and Magnetic Resonance Imaging.

Embolotherapies used in the treatment of hepatocellular carcinoma (HCC) include bland embolization, conventional transarterial chemoembolization (cTACE) using ethiodol as a carrier, TACE with drug-eluting beads and super absorbent polymer microspheres (DEB-TACE), and selective internal radiation therapy (SIRT). Successfully treated HCC lesions undergo coagulation necrosis, and appear as nonenhancing hypoattenuating or hypointense lesions in the embolized region on computed tomography (CT) and magnetic resonance. Residual or recurrent tumours demonstrate arterial enhancement with portal venous phase wash-out of contrast, features characteristic of HCC, in and/or around the embolized area. Certain imaging features that result from the procedure itself may limit assessment of response. In conventional TACE, the high-attenuating retained ethiodized oil may obscure arterially-enhancing tumours and limit detection of residual tumours; thus a noncontrast CT on follow-up imaging is important post-cTACE. Hyperenhancement within or around the treated zone can be seen after cTACE, DEB-TACE, or SIRT due to physiologic inflammatory response and may mimic residual tumour. Recognition of these pitfalls is important in the evaluation embolotherapy response.

Radiological Evaluation of Abdominal Endovascular Aortic Aneurysm Repair.

Endovascular aortic aneurysm repair (EVAR) is an alternative to open surgical repair of aortic aneurysms offering lower perioperative mortality and morbidity. As experience increases, clinicians are undertaking complex repairs with hostile aortic anatomy using branched or fenestrated devices or extra components such as chimneys to ensure perfusion to visceral branch vessels whilst excluding the aneurysm. Defining the success of EVAR depends on both clinical and radiographic criteria, but ultimately depends on complete exclusion of the aneurysm from the circulation. Aortic stent grafts are monitored using a combination of imaging modalities including computed tomography angiography (CTA), ultrasonography, magnetic resonance imaging, plain films, and nuclear medicine studies. This article describes when and how to evaluate aortic stent grafts using each of these modalities along with the characteristic features of several of the main stent grafts currently used in clinical practice. The commonly encountered complications from EVAR are also discussed and how they can be detected using each imaging modality. As the radiation burden from serial follow up CTA imaging is now becoming a concern, different follow-up imaging strategies are proposed depending on the complexity of the repair and based on the relative merits and disadvantages of each imaging modality.

The Role of Contrast-enhanced Ultrasound in Guiding Radiofrequency Ablation of Hepatocellular Carcinoma: A Retrospective Study.

PURPOSE: The objective of the study was to determine the efficacy of contrast-enhanced ultrasound (CEUS) using ultrasound (US)-specific microbubbles in guiding radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC). METHODS: A retrospective analysis of 50 patients with HCC treated with CEUS guided RFA using perflutren at our institution was performed. CEUS images were first compared to B-mode US images performed at the same RFA session to determine the ability of CEUS to increase the conspicuity of lesions. A qualitative score (1 = poor, 2 = fair, 3 = excellent) was used to grade the ability to visualize the lesions. The preprocedure CEUS images were then evaluated using the most recent prior contrast enhanced computed tomography (CT) or magnetic resonance imaging (MRI). The efficacy of the treatment was evaluated with short-term follow-up imaging (median 1 month) for presence of residual or recurrent disease. RESULTS: CEUS allows at least fair visualization (score ≥2) in 78% (reader 1) and 80% (reader 2) of the lesions not visualized by B-mode US, and 50% (reader 1) and 42% (reader 2) of the lesions poorly visualized by B-mode US. Lesion appearances on CEUS are largely concordant with those on CT or MRI: 88% for reader 1, 96% for reader 2. With CEUS-guided RFA, complete response was achieved in the vast majority of the lesions at short-term follow-up: 82% for reader 1, 94% for reader 2. CONCLUSIONS: CEUS increases the conspicuity and provides better characterization of hypervascular HCC that are either not seen or poorly seen on B-mode US, and CEUS provides real-time guidance of RFA with good short-term treatment responses.

Novel use of the Surefire antireflux device in subtotal splenic embolization.

An unstable patient presented with an enlarging splenic hematoma, for whom splenectomy was contraindicated. The decision was made to treat this patient with subtotal splenic embolization. Initial attempts at embolotherapy using a conventional end-hole catheter resulted in a false angiographic end point with reflux into short gastric arteries, likely due to splenic parenchymal pressurization from the hematoma. The Surefire antireflux device (Surefire Medical Inc, Westminster, Colo) was therefore employed. The Surefire device allowed successful subtotal splenic embolization. Whereas it is currently primarily used in hepatic interventional oncology, we have shown that it can be successfully used in other settings to increase embolization efficiency while mitigating nontargeted embolization.

The effect of doxorubicin loading on response and toxicity with drug-eluting embolization in resectable hepatoma: a dose escalation study.

AIM: The dose-response relationship between doxorubicin and superabsorbent drug-eluting microspheres has not been established. In this study, we investigated the relationships between dose and delivery parameters as they pertain to toxicity and response in surgically resectable hepatocellular carcinoma (HCC). PATIENTS AND METHODS: Twenty-five patients with resectable HCC were randomly assigned and divided into four groups, each receiving either bland, 25 mg, 50 mg or 75 mg of doxorubicin loaded Super Absorbent Polymer microspheres, with 24 patients undergoing surgical resection. Response Evaluation and Criteria in Solid Tumors (RECIST) 1.0 and European Association for the Study of the Liver (EASL)-based volumetric response was performed at one month and surgical resection of the reference tumor was performed at two months. Adverse events were collected at regular intervals. RESULTS: Fifty-six percent of patients demonstrated complete response according to EASL criteria as opposed to 0% according to RECIST (v1.0) criteria. Residual tumor was identified in all groups (0 mg: 35%±28.5%; 25 mg: 42%±30.4%; 50 mg: 3.6%±3.3%; and 75 mg: 49.29%±32.6%. A total of 112 adverse events of grades 1-3 occurred (average 5.1 per patient), with no grade 4 or 5. No difference was noted between bland embolic and drug-loaded groups. Subset analysis did demonstrate a significantly increased degree of necrosis in the 50 mg-loaded group (p=0.018). Strong correlation existed between arterial phase Computer Tomography EASL-based response and histopathology (r=0.81; p<0.0001). All groups had residual tumor. CONCLUSION: Histology correlates strongly with one-month post-procedural imaging and response optimized at 50 mg of loading per vial. Adverse events were a reflection of embolization, with no relationship between loading dose or administered dose of doxorubicin.

A practical guide to magnetic resonance vascular imaging: techniques and applications.

Magnetic resonance angiography is a technique used to image both central and peripheral arteries using contrast and noncontrast techniques. These techniques are similar in that a bright signal, which appears white within blood vessels, is generated and the background tissues, veins, and stationary tissues are dark. This allows for assessment of anatomy and vascular disease. Extracellular gadolinium-based contrast agents allow for excellent visualization of both central and peripheral arteries. Acquiring images during first pass is required for high-contrast images within arteries, thereby limiting contamination with contrast enhancement of veins and soft tissue. Contrast-enhanced techniques using time-resolved angiography and blood pool contrast agents minimize this temporal limitation. Noncontrast techniques eliminate the uncommon but potentially fatal complications associated with gadolinium contrast agents, such as nephrogenic systemic fibrosis. These techniques including phase contrast and time-of-flight sequences have inferior contrast resolution compared with contrast-enhanced techniques and are susceptible to artifacts, which can limit interpretation. The advantage, however, is the ability to assess vascular disease in patients with severe renal failure without the added risks of gadolinium contrast media. The aim of this review is to outline the different techniques available for imaging both the arterial and venous systems, their advantages and disadvantages, and the indications in vascular disease.

Pulmonary ablation: a primer.

Percutaneous image-guided thermal ablation is safe and efficacious in achieving local control and improving outcome in the treatment of both early stage non-small-cell lung cancer and pulmonary metastatic disease, in which surgical treatment is precluded by comorbidity, poor cardiorespiratory reserve, or unfavorable disease distribution. Radiofrequency ablation is the most established technology, but new thermal ablation technologies such as microwave ablation and cryoablation may offer some advantages. The use of advanced techniques, such as induced pneumothorax and the popsicle stick technique, or combining thermal ablation with radiotherapy, widens the treatment options available to the multidisciplinary team. The intent of this article is to provide the reader with a practical knowledge base of pulmonary ablation by concentrating on indications, techniques, and follow-up.

Hepatic artery transection reconstructed with splenic artery transposition graft.

INTRODUCTION: Hepatic artery transection presents a technical challenge in vascular reconstruction. Formal arterial repair is indicated in patients with underlying liver disease and those undergoing bile duct reconstructions because of a higher risk of complication following hepatic artery injury. This report highlights a novel approach to hepatic artery transection with splenic artery transposition. METHODS: A case of hepatic artery transection repaired with splenic artery transposition is presented with an accompanying literature review. RESULTS: During elective pancreaticoduodenectomy, the common hepatic artery was injured at its origin. The splenic artery was divided and transposed to the hepatic artery, thus restoring arterial flow to the liver and bile duct. CONCLUSION: Various strategies to manage a hepatic artery injury have been described, ranging from ligation to complex vascular reconstruction. In hemodynamically stable patients, arterial transposition using the splenic artery is a feasible method to ensure adequate arterial supply to the liver and biliary tract.