Preliminary Experience with a Low-Profile High-Density Braid Occluder for Transcatheter Embolization of Pulmonary Arteriovenous Malformations.

This brief report describes safety, technical feasibility, and early treatment effectiveness of the low-profile braided occluder (LOBO; Okami Medical, San Diego, Caliornia) for embolization of 9 pulmonary arteriovenous malformations (PAVMs) in 4 patients (3 female and 1 male; age range: 33 to 63 years; 3 patients showed positive results for hereditary hemorrhagic telangiectasia genes). A total of 10 occluders were deployed in 10 vessels (median treated vessel diameters, 3 and 4 mm for LOBO-3 and LOBO-5 groups, respectively). All devices were successfully deployed into the feeder pulmonary arteries, achieving complete cessation of flow. There were no severe adverse events or device migrations. Available short-term follow-up computed tomography (6 PAVMs: median, 7 months; range, 1.5-7 months) demonstrated complete occlusion without persistence or recanalization. The early experience of embolization of PAVMs using a low-profile braided occluder showed it to be safe and effective. Further studies with larger cohorts and longer follow-up periods are warranted.

Segmental Yttrium-90 Radioembolization Using Glass Microspheres Greater than 400 Gray for the Treatment of Intrahepatic Cholangiocarcinoma: A Preliminary Experience.

Radiation segmentectomy with a dose of >190 Gy using yttrium-90 (90Y) glass microspheres for intrahepatic cholangiocarcinoma (iCCA) has been shown to be safe and effective. The present study further increased the dose to >400 Gy for treatment of iCCA as complete pathologic necrosis has been shown in hepatocellular carcinoma using this ablative approach. A total of 10 patients with 13 tumors (median size, 5.3 cm; range, 1.5-13.6 cm) at a single institution underwent >400-Gy segmental radioembolization. Objective response was achieved in all tumors (13 of 13, 100%). One patient developed a Grade 3 or greater major adverse event (stroke and hepatic decompensation). One patient was bridged to transplant (>95% pathologic necrosis), whereas another underwent resection (>99% necrosis). Contralateral hypertrophy was observed in 6 out of 6 patients treated with modified lobectomy dosing, with a functional liver reserve increase from a median of 31.5% to 57.1%. The present report suggests that segmental transarterial radioembolization with >400 Gy is feasible in terms of safety and effectiveness for treating iCCA.

Post-Hoc Analysis of a Randomized, Double Blind, Prospective Study at the University of Chicago: Additional Standardizations of Trial Protocol are Needed to Evaluate the Effect of a CXCR1/2 Inhibitor in Islet Allotransplantation.

A recent randomized, multicenter trial did not show benefit of a CXCR1/2 receptor inhibitor (Reparixin) when analysis included marginal islet mass (>3,000 IEQ/kg) for allotransplantation and when immunosuppression regimens were not standardized among participating centers. We present a post-hoc analysis of trial patients from our center at the University of Chicago who received an islet mass of over 5,000 IEQ/kg and a standardized immunosuppression regimen of anti-thymocyte globulin (ATG) for induction. Twelve islet allotransplantation (ITx) recipients were randomized (2:1) to receive Reparixin (N = 8) or placebo (N = 4) in accordance with the multicenter trial protocol. Pancreas and donor characteristics did not differ between Reparixin and placebo groups. Five (62.5%) patients who received Reparixin, compared to none in the placebo group, achieved insulin independence after only one islet infusion and remained insulin-free for over 2 years (P = 0.08). Following the first ITx with ATG induction, distinct cytokine, chemokine, and miR-375 release profiles were observed for both the Reparixin and placebo groups. After excluding procedures with complications, islet engraftment on post-operative day 75 after a single transplant was higher in the Reparixin group (n = 7) than in the placebo (n = 3) group (P = 0.03) when islet graft function was measured by the ratio of the area under the curve (AUC) for c-peptide to glucose in mixed meal tolerance test (MMTT). Additionally, the rate of engraftment was higher when determined via BETA-2 score instead of MMTT (P = 0.01). Our analysis suggests that Reparixin may have improved outcomes compared to placebo when sufficient islet mass is transplanted and when standardized immunosuppression with ATG is used for induction. However, further studies are warranted. Investigation of Reparixin and other novel agents under more standardized and optimized conditions would help exclude confounding factors and allow for a more definitive evaluation of their role in improving outcomes in islet transplantation. Clinical trial reg. no. NCT01817959, clinicaltrials.gov.

Empiric Transcatheter Embolization for Acute Arterial Upper Gastrointestinal Bleeding: A Meta-Analysis.

OBJECTIVE. The purpose of this study was to conduct a meta-analysis to assess the safety and efficacy of empiric embolization compared with targeted embolization in the treatment of acute upper gastrointestinal bleeding (UGIB). MATERIALS AND METHODS. We searched the PubMed and Cochrane Library databases for studies performed without language restrictions from January 2000 to November 2019. Only clinical studies with a sample size of five or more were included. Clinical success, rebleeding and complication rates, survival rates, bleeding cause, embolic materials, and vessels embolized were recorded. Empiric embolization and targeted embolization (i.e., embolization performed based on angiographic evidence of ongoing bleeding) were compared when possible. Meta-analysis was performed. RESULTS. Among 13 included studies (12 retrospective and 1 prospective), a total of 357 of 725 patients (49.2%) underwent empiric embolization for UGIB. The clinical success rate of empiric embolization was 74.7% (95% CI, 63.1-86.3%) among the 13 studies, and the survival rate was 80.9% (95% CI, 73.8-88.0%) for 10 studies. On the basis of comparative studies, no statistically significant difference was observed between empiric and targeted embolization in terms of rebleeding rate in 111 studies (36.5% vs 29.6%; odds ratio [OR], 1.13; 95% CI, 0.77-1.65; p = .53), mortality in eight studies (23.3% vs 18.0%; OR, 1.44; 95% CI, 0.89-2.33; p = .14), and need for surgery to control rebleeding in four studies (17.8% vs 13.4%; OR, 1.34; 95% CI, 0.58-3.07; p = .49). The pooled embolization-specific complications were 1.9% (empiric) and 2.4% (targeted). CONCLUSION. According to all available published evidence, empiric embolization assessed with endoscopic or preprocedural imaging findings (or both) appears to be as effective as targeted embolization in preventing rebleeding and mortality in patients with angiographically negative acute UGIB. Because of its favorable safety profile, empiric embolization should be considered for patients in this clinical scenario.

Hybrid angiography-CT for transarterial radioembolization: a pictorial essay.

Although hybrid angiography-CT (Angio-CT) has a long history of use for interventional oncology procedures, its applications for transarterial radioembolization (TARE) are not as well described in the literature. This pictorial essay demonstrates a single-institution experience with the utilization of an Angio-CT system for TARE treatment of hepatocellular carcinoma. Procedural images and clinical data for twenty-four patients who underwent initial angiographic mapping with hepatopulmonary shunt fraction assessment and or administration of Yttrium-90 (Y-90) microspheres using the Angio-CT system to date were reviewed. Cases were reviewed for examples that highlight the specific utility of Angio-CT. Three representative TARE cases were selected which illustrate unique advantages and applications of the Angio-CT system when performing TARE. These include the ability to optimally delineate hepatic vascular anatomy, accurately calculate liver volumes for dosimetry, and improve the detection and characterization of equivocal lesions. Angio-CT has unique advantages which can be applied to TARE treatment of patients with HCC. The technology has potential to be an especially effective tool for those who aim to be at the cutting edge of the rapidly growing field of interventional oncology.

Safety and efficacy of repeat Y90 radioembolization to the same hepatic arterial territory.

OBJECTIVE: To study the efficacy and safety of repeat transarterial radioembolization (TARE) to similar hepatic arterial territories. METHODS: Between 3/2011 and 4/2019, 26 patients (25 males and 1 Female, Mean Age: 65 yo, SD: 11.7 yo, Range: 18-83.0 yo) received TARE with Y90 glass microspheres to treat recurrent or residual primary disease in similar hepatic arterial lobe or segments. Tumor response was evaluated by imaging using the modified-RECIST criteria. Incidence of RILD and adverse events were categorized by a standardized scale using the Common Terminology Criteria for Adverse Events (CTCAE) v.4.0. RESULTS: Mean cumulative activity after the first treatment was 2.50 GBq (SD:1.04 GBq, Range:0.61-4.93 GBq) and second treatment was 2.27 GBq (SD:1.01 GBq, Range:0.92-5.46 GBq). Mean interval time between initial and repeat treatments was 9.6 months (Range: 1-53 months). Tumor responses were complete, partial, or progression in 73% (n = 19/26), 23% (n = 6/26), and 4% (n = 1/26) in repeat treatment patients, respectively. The incidence of RILD was 0%. Toxicity after first and second treatment was seen in 19% (n = 5/26) & 23% (n = 6/26) patients, respectively, and were all of CTCAE Grade 2. No significant predictors of treatment toxicity for repeat treatment were identified except increased MELD score (p = 0.04). Kaplan-Meier survival analysis in patients with repeat treatment showed a median survival of 15.0 months (95% CI 8.8-21.1 months) and 19.0 months (95% CI 8.1-29.9 months) in patients who only received one treatment with a p value of 0.485. CONCLUSION: Repeat TARE with glass microspheres was an effective and safe treatment strategy for disease management in patients with residual or recurrent disease to the similar hepatic arterial territories without any major treatment related toxicity. ADVANCES IN KNOWLEDGE: Although safety and efficacy of repeat radioembolism has been studied, no study has focused on repeat treatment to similar hepatic arterial territories. The current study shows that repeat treatment to the same hepatic arterial territory is as safe as single treatment to the same territory.

Social Media Growth at Annual Medical Society Meetings: A Comparative Analysis of Diagnostic and Interventional Radiology to Other Medical Specialties.

OBJECTIVE: To understand social media growth in both diagnostic and interventional radiology compared to other related specialties by quantifying and comparing hashtag utilization at annual medical conferences. METHODS: Official annual conference hashtags for Society of Interventional Radiology (SIR), American College of Radiology (ACR), Radiological Society of North America, American College of Cardiology, American Heart Association, and American Society of Clinical Oncology were analyzed from 2015 to 2019, along with the IR hashtag #IRad. Twitter analytics were obtained with the use of Symplur Signals, a healthcare social media analytics platform. Linear regression analysis was performed on the number of tweets and users for each hashtag. RESULTS: For annual ACR meetings, the number of tweets/user (6.96 in 2019), retweets/user (4.39 in 2019), and impressions/user (40,051 in 2019) were among the highest of all the specialties studied. This trend was observed despite a smaller number of users among ACR than most other conferences. SIR tweets increased significantly at a rate of 1032.8 tweets/year (P = 0.008) while users also significantly grew at a rate of 212.5 users/years (P = 0.007). #IRad tweets are also growing at a rate of 13,234.8 tweets/year (P = 0.026) while #IRad users are growing at a rate of 1309.5 users/year (P = 0.003). Radiological Society of North America users were significantly decreasing at -1207.1 users/year (P = 0.018). CONCLUSION: ACR consistently had one of the highest counts of tweets/user, retweets/user, and impressions/user compared to the other studied specialties, suggesting that ACR's Twitter users are more active than users outside of the field of radiology. SIR was the only studied specialty conference that had statistically significant increases in the number of tweets and users.

Yttrium-90 Radioembolization Therapy for Combined Hepatocellular and Cholangiocarcinoma.

PURPOSE: To report outcomes of transarterial radioembolization (TARE) using glass microspheres for the treatment of mixed hepatocellular-cholangiocarcinoma (HCC-CC) in a propensity-matched study. MATERIAL AND METHODS: Between 2013 and 2019, 10 consecutive patients with histologically confirmed HCC-CC received TARE of a targeted territory using glass microspheres as a primary initial treatment. Baseline demographics in addition to tumor distribution, Child Pugh score, and BCLC were recorded. Tumor response was assessed according to modified RECIST criteria. The HCC-CC cohort was matched to the HCC cohort, and objective response and survival analysis was performed. RESULTS: In the HCC-CC cohort, patients had a 70% objective response rate (ORR), and in the HCC cohort, patients had a 90% ORR after matching (p = 0.54). The median overall survival (OS) for HCC patients was 12.3 months (95% CI: 6.0-17.4 months) in the matched population, and for HCC-CC patients, the median OS was 15.2 months (95% CI: 2.7-20.2 months) (p = 0.98). The median progression-free survival (PFS) for HCC patients was 11.6 months (95% CI: 2.53-19.3 months) in the matched population, and for HCC-CC patients, the median PFS was 15.2 months (95% CI: 2.7-20.2 months) (p = 0.94). The median transplant-free survival (TFS) for HCC patients was 12.3 months (95% CI: 6.0-17.4 months) in the matched population, and for HCC-CC patients, the median TFS was 15.2 months (95% CI: 2.7-20.2 months) (p = 0.98). CONCLUSIONS: While outcomes of combined HCC-CC are poor and optimal treatment remains undefined, TARE appears to represent an effective locoregional treatment with survival outcomes similar to that of HCC treated by TARE.

Improved Utilization Following Conversion of a Fluoroscopy Suite to Hybrid CT/Angiography System.

PURPOSE: To assess changes in operational utilization following conversion of a single IR suite to a hybrid CT/angiography (Angio-CT) system at an academic tertiary care center. MATERIALS AND METHODS: The total number of interventional procedures and diagnostic CT examinations performed in 29 rooms (20 diagnostic radiology, 7 IR, 2 shared between divisions) was calculated in the 24 months before conversion of an IR suite to Angio-CT and 12 months after conversion. The total number of IR procedures (global IR/month) and diagnostic CT scans per month (global CT/month) in both before and after conversion periods was calculated and defined as baseline institutional growth. This was compared against the change in the number of IR procedures performed in the before and after periods in the converted room (Angio-CT/month) as well as the number of diagnostic CT scans performed in the shared rooms (shared CT/month). RESULTS: The percent change in global CT and global IR from the before to the after periods was 39.2% and 3.1%, respectively. Shared CT per month and Angio-CT per month increased by 46.7% and 12.0% across the same time periods, respectively. The ratio of the percent increase in Angio-CT per month to percent increase in global IR per month was 3.87. The ratio of the percent increase in shared CT per month to percent increase in global CT per month was 1.19. CONCLUSIONS: Operational utilization improved in both diagnostic radiology and IR sections following conversion of a conventional fluoroscopic IR suite to an Angio-CT room.

Interventional Radiology in Pelvic Trauma.

Traumatic pelvic injuries are associated with high injury severity scores and significant morbidity and mortality. As fractures and ligamentous disruption result in increased pelvic volume, retroperitoneal hemorrhage can spiral and progress to hemorrhagic shock. Due to the extensive collateral supply and limitations of surgery for pelvic hematomas, angiographic treatment is at the forefront of pelvic trauma management. This article will discuss typical injuries seen in pelvic trauma, treatment modalities available to the interventional radiologist, and common angiographic treatment strategies and techniques.

Transsplenic portal vein recanalization and direct intrahepatic portosystemic shunt placement to optimize liver transplantation.

BACKGROUND: Percutaneous trans-splenic portal vein recanalization (PVR) has been reported for facilitation of transjugular intrahepatic portosystemic shunts (TIPS), however has not been applied to patients undergoing direct intrahepatic portosystemic shunt (DIPS). We report the utilization of trans-splenic-PVR with DIPS creation in a patient with chronic portal and hepatic vein occlusions undergoing liver transplantation evaluation. CASE PRESENTATION: A 48-year-old male with decompensated alcoholic cirrhosis complicated by refractory ascites, hepatic encephalopathy, and variceal bleeding underwent CT that demonstrated chronic occlusion of the hepatic veins (HV), extrahepatic portal vein (PV), and superior mesenteric vein (SMV). Due to failed attempts at TIPS at outside institutions, interventional radiology was consulted for portal vein recanalization (PVR) with TIPS to treat the portal hypertension and ascites and also facilitate an end-to-end PV anastomosis at transplantation. After an initial hepatic venogram confirmed chronic HV occlusion, a DIPS with trans-splenic PVR was planned. The splenic vein was accessed under sonographic guidance using a micropuncture set and subsequently upsized to a 6 French sheath over a stiff guidewire. A splenic venogram via this access confirmed occlusion of the PV with drainage of the splenic vein (SV) through gastric varices. The thrombosed PV was then recanalized and angioplastied to restore PV flow via the transsplenic approach. A transjugular liver access kit with a modified 21-gauge needle was advanced into the IVC through the internal jugular vein (IJV) sheath and directed towards the target snare in PV. The needle was used to subsequently puncture the PV through the caudate lobe and facilitate placement of a wire into the SV. The initial portosystemic gradient (PSG) was 20 mmHg. The IJV sheath was advanced through the hepatic parenchymal tract into the main-PV and a stent-graft was placed across the main PV and into the IVC. A portal venogram demonstrated brisk blood flow through the DIPS, resolution of varices and a PSG of 8 mmHg. One month after the procedure, the patient had a significant reduction in ascites and MELD-NA score. Patient is currently listed and awaiting transplantation. CONCLUSIONS: In the setting of chronically occluded portal and hepatic veins, trans-splenic PVR DIPS may serve as an effective bridge to liver transplantation by facilitating an end to end portal vein anastomosis.

Lung and Abdominal Biopsies in the Age of Precision Medicine.

Image-guided percutaneous needle biopsies (PNBs) are one of the most common procedures performed in radiology departments today. Rapid developments in precision medicine, which identifies molecular and genomic biomarkers in cancers, have ushered a new paradigm of oncologic workup and treatment. PNB has conventionally been used to establish a benign or malignant nature of a lesion during initial diagnosis or in suspected metastatic or recurrent disease. However, increasing amounts of tissue are being required to meet the demands of molecular pathologic analysis, which are now being sought at multiple time points during the course of the disease to guide targeted therapy. As primary providers of biopsy, radiologists must be proactive in these developments to improve diagnostic yield and tissue acquisition in PNB. Herein, we discuss the important and expanding role of PNB in the age of precision medicine and review the technical considerations of percutaneous lung and intra-abdominal biopsy. Finally, we examine promising state-of-the-art techniques in PNB that may safely increase tissue acquisition for optimal molecular pathologic analysis.

Benign Biliary Strictures.

Differentiating benign and malignant biliary strictures is a challenging and important clinical scenario. The typical presentation is indolent and involves elevation of liver enzymes, constitutional symptoms, and obstructive jaundice with or without superimposed or recurrent cholangitis. While overall the most common causes of biliary strictures are malignant, including cholangiocarcinoma and pancreatic adenocarcinoma, benign strictures encompass a wide spectrum of etiologies including iatrogenic, autoimmune, infectious, inflammatory, and congenital. Imaging plays a crucial role in evaluating strictures, characterizing their extent, and providing clues to the ultimate source of biliary obstruction. While ultrasound is a good screening tool for biliary ductal dilatation, it is limited by a poor negative predictive value. Magnetic resonance cholangiopancreatography is more than 95% sensitive and specific for detecting biliary strictures with the benefit of precise anatomic localization. Other commonly employed imaging modalities include endoscopic retrograde cholangiopancreatography with endoscopic ultrasound, contrast-enhanced CT, and cholangiography. First-line treatment of benign biliary strictures is endoscopic dilation and stenting. In patients with anatomy that precludes endoscopic cannulation, percutaneous biliary drain insertion and balloon dilation is preferred.

Delayed Diagnosis of Mirizzi Syndrome.

Biliary obstruction occurs in a wide variety of malignant and benign conditions. The following is a unique case of biliary obstruction caused by external compression of the hepatic duct by a gallstone (Mirizzi syndrome). Owing to unusual imaging characteristics of the stone, the mass was initially mistaken for a malignancy or hepatic pseudoaneurysm. It was not until the patient developed gallstone ileus that the correct diagnosis was made.

Core Lung Biopsy for Biomarker Analysis: Is There Increased Risk Compared With Conventional Biopsy?

PURPOSE: The aim of the study was to compare the rate of pneumothorax and chest tube placement in patients undergoing conventional lung biopsy with those undergoing core lung biopsy for biomarker analysis. MATERIALS AND METHODS: Twenty-three patients had biopsies performed for biomarker analysis (5 male, 18 female patients, mean age 67 y), and 173 patients underwent standard diagnostic lung biopsy (86 male, 87 female patients, mean age 68 y). All biopsies were performed under computed tomography guidance using the coaxial technique (19 G introducer needle and 20 G core biopsy needle). The number of core samples was noted for each case, and all complications were recorded in accordance with Society of Interventional Radiology guidelines. RESULTS: In the biomarker analysis group, a mean of 5.1 core samples (range, 1 to 10) was obtained. In the conventional biopsy group, a mean of 2.9 core samples (range, 1 to 6) was obtained. The pneumothorax rate was 37.6% in the conventional biopsy group and 30.4% in the biomarker analysis group (P=0.505). The rate of chest tube placement was 16.8% in the conventional biopsy group and 8.7% in the biomarker analysis group (P=0.319). Lesion size was found to be an independent predictor of pneumothorax (P=0.031), whereas biopsy tract length was found to be an independent predictor of both pneumothorax (P<0.001) and chest tube placement (P=0.005) upon multivariate analysis. CONCLUSIONS: There is no statistically significant difference in the incidence of pneumothorax or chest tube placement between patients undergoing standard diagnostic lung biopsy and those requiring increased core samples for biomarker analysis.