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.

Segmental Yttrium-90 Radioembolization as an Initial Treatment for Solitary Unresectable HCC

Objectives To evaluate the objective response rate (ORR), time to progression (TTP), and overall survival (OS) in patients with unresectable solitary HCC less than 5 cm who were treated with 90Y glass microspheres infused at a segmental level.

Materials and Methods Single-institution retrospective study of 35 patients with unresectable HCC deemed not suitable for percutaneous ablation who underwent segmental transarterial radioembolization (TARE) treatment. Eligibility criteria included patients with solitary, unilobar, < 5 cm unresectable HCC lesions who underwent TARE as a primary treatment strategy between November 2012 and April 2020. Imaging follow-up was performed on each patient at 3-, 6-, and 12 months post-treatment. Local and the overall tumor response was evaluated using mRECIST criteria, and primary endpoints were ORR, TTP, and OS. Adverse events (AEs) were graded for severity using the Common Terminology Criteria for Adverse Events (CTCAE) v.5.0.

Statistical Analysis Patient demographics, baseline characteristics, and treatment characteristics were analyzed using descriptive statistics. Predictors of survival were analyzed with Cox proportional hazards regression. Kaplan–Meier analysis was used to evaluate OS.

Results Median tumor size was 3 cm (range: 1.0-4.8 cm) in the 35 patients studied, with 25.7% (9/35) being the Eastern Cooperative Oncology Group (ECOG) 0 and 62.9% (22/35) ECOG 1. Most patients (88.5%, 31/35) were of the Barcelona Clinic Liver Cancer (BCLC) stage C, with one patient each classified as BCLC-A and BCLC-0, respectively. For 34.2% (12/35), TARE functioned as a bridge to transplantation. Transplanted patients exhibited a median pathologic necrosis of 98% (IQR 7.5). Combined ORR for local and overall mRECIST at 12 months post-TARE was 94.3% and 85.7%, respectively. All patients had a mean local TTP of 11.9 months (CI: 2.7–21.0) and global TTP of 13.2 months (CI: 6.4–20.0). Among the 14.3% (5/35) of patients who experienced AEs following treatment, 80% (4/5) were Grade 1, one patient experienced a Grade 4, and all events resolved within 1 month of treatment. Total OS at 1 year was 97%, whereas patients who underwent OLT had an OS of 100%.

Conclusion Segmental TARE was a safe and effective treatment for solitary unresectable HCC less than 5 cm. When used as a bridge to transplant, explants showed near complete pathologic necrosis of treated lesions.

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.

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.

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.

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.

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.

Strut penetration: local complications, breakthrough pulmonary embolism, and retrieval failure in patients with Celect vena cava filters

PURPOSE

To investigate strut penetration in patients with Celect filters, specifically local complications and association with breakthrough pulmonary embolism (PE) or retrieval failure.

MATERIALS AND METHODS

A retrospective single-center study was conducted to evaluate patients who received Celect filters between January 2007 and May 2013. A total of 595 filters were placed during the study period. Primary indications included thromboembolic disease (93%) and primary surgical prophylaxis (7%). Complications and retrieval data were assessed by computed tomography (CT) and electronic medical records.

RESULTS

A total of 193 patients underwent follow-up abdominal CT at a mean follow-up interval of 176.2 days (range, 0-1,739 d). The rate of strut penetration more than 3 mm outside the caval wall was 28.5% (n = 55). One patient had CT evidence of clinically major strut penetration (1.8%) with strut compression of the right ureter causing hydronephrosis. Indwelling filter time longer than 100 days was associated with strut penetration (P < .001). Age, sex, and history of thromboembolic disease were not associated with strut penetration (P = .51, P = .81, and P = .89). Sixty-three patients presented for follow-up CT pulmonary angiography at a mean of 128.1 days (range, 1-895 d). The rate of breakthrough PE was 12.7%. The overall retrieval success rate was 96.7% (n = 150). Strut penetration was not associated with breakthrough PE or retrieval failure (P = .49 and P = .22).

CONCLUSIONS

Although strut penetration is a common complication with Celect filters, there is no association with breakthrough PE or retrieval failure. CT evidence of local complications associated with strut penetration is rare.

Comparison of barbed versus conventional sutures for wound closure of radiologically implanted chest ports

PURPOSE

To retrospectively compare the incidences of complications with barbed suture versus conventional interrupted suture for incision closure in implantable chest ports.

MATERIALS AND METHODS

A total of 715 power-injectable dual-lumen chest ports placed between 2011 and 2013 were studied. Primary outcomes included wound dehiscence, local port infection, local infections treated by wound packing, early infections within 30 days, and total infections. A multivariate analysis of independent risk factors for port infection was also performed.

RESULTS

A total of 442 ports were closed with nonbarbed suture, versus 273 closed with barbed suture. Mean catheter-days in the traditional and barbed groups were 257.9 (range, 3-722) and 189.1 (range, 13-747), respectively (P < .01). The rate of dehiscence with traditional suture (1.6%; seven of 442) was significantly higher than that with barbed suture (zero of 273; P = .04). Percentage of total infections was also significantly higher with traditional suture (9.5% vs 5.1%; P = .03). No difference in rate of infection per 1,000 catheter-days was seen between traditional and barbed suture groups (0.0035 vs 0.0026; P = .17). The rate of local infection with traditional suture was significantly higher (2.7% vs 0.4%; P = .02). Additionally, multivariate analysis identified the use of traditional suture as the only independent risk factor for infection (39% vs 25%; P = .03).

CONCLUSIONS

Barbed suture for incision closure in implantable dual-lumen chest ports was associated with lower rates of dehiscence and potentially lower rates of local infectious complications compared with traditional nonbarbed suture.

Emergent management of empyema

Empyema is a frankly purulent infection of the pleural space most often occurring secondary to parapneumonic effusion. Imaging, specifically contrast-enhanced computed tomography, plays a critical role in diagnosis with a "split pleura" sign being highly suggestive in the appropriate clinical setting. Diagnostic thoracentesis with culture and Gram stain further guides appropriate antibiotic therapy. Therapeutic drainage with small-bore tube thoracostomy has been shown to be a safe and effective treatment of early stage empyema. Augmentation of tube placement with intrapleural fibrinolytics and mucolytics facilitates catheter drainage by degrading loculations and decreasing fluid viscosity, respectively.

Delayed presentation of rupture after venous angioplasty

Venous rupture is an uncommon complication resulting from dialysis graft interventions. We present a case in which contrast extravasation recurred following an initially successful balloon tamponade. The rupture site could not be negotiated with a guidewire to provide endovascular treatment, necessitating balloon occlusion of the graft.