Impact of Portal Hypertension on Adverse Events after Splenic Arterial Aneurysm Embolization

PurposeTo evaluate the outcomes of splenic artery aneurysm (SAA) embolization and compare adverse event (AE) rates after embolization in patients with and without portal hypertension (PHTN).Materials and MethodsA retrospective review of all patients who underwent embolization of SAAs at 2 institutions was performed (34 patients from institution 1 and 7 patients from institution 2). Baseline demographic characteristics, preprocedural imaging, procedural techniques, and postprocedural outcomes were evaluated. Thirty-day postprocedural severe and life-threatening AEs were evaluated using the Society of Interventional Radiology guidelines. Thirty-day mortality and readmission rates were also evaluated. t test, χ² test, and/or Fisher exact test were used for the statistical analysis.ResultsThere was no statistically significant difference between patients with and without PHTN in the location, number, and size of SAA(s). All procedures were technically successful. There were 13 (32%) patients with and 28 (68%) patients without PHTN. The 30-day mortality rate (31% vs 0%; P = .007), readmission rates (61% vs 7%; P < .001), and severe/life-threatening AE rates (69% vs 0%; P < .001) were significantly higher in patients with PHTN than in those without PHTN.ConclusionsThere was a significantly higher mortality and severe/life-threatening AE rate in patients with PHTN than in those without PHTN. SAAs in patients with PHTN need to be managed very cautiously, given the risk of severe/life-threatening AEs after embolization.     

Risk Factors for Hemorrhagic Adverse Events in Percutaneous Transhepatic Biliary Drainage: A Prospective Multicenter Study

PurposeTo determine risk factors (RFs) for hemorrhagic adverse events (AEs) associated with percutaneous transhepatic biliary drainage (PTBD) and to develop a risk assessment model.Materials and MethodsThis was a multicenter, prospective, case control study between 2015 and 2020. Adults with an indication for PTBD were included. Patients who had undergone recent previous drainage procedures were excluded. Multiple variables were controlled. The exposure variables were the number of capsular punctures and passes (using the same puncture). A multivariate analysis was performed (logistic regression analysis).ResultsA total of 304 patients (mean age, 63 years ± 14 [range, 23–87 years]; female, 53.5%) were included. Hemorrhagic AEs occurred in 13.5% (n = 41) of the patients, and 3.0% (n = 9) of the cases were severe. Univariate analysis showed that the following variables were not associated with hemorrhagic AEs: age, sex, bilirubin and hemoglobin levels, type of pathology, portal hypertension, location of vascular punctures, ascites, nondilated bile duct, intrahepatic tumors, catheter features, blood pressure, antiplatelet drug use, and tract embolization. Multivariate analysis showed that number of punctures (odds ratio [OR], 2.5; P = .055), vascular punctures (OR, 4.1; P = .007), fatty liver or cirrhosis (OR, 3.7; P = .021), and intrahepatic tumor obstruction (Bismuth ≥ 2; OR, 2.4; P = .064) were associated with hemorrhagic AEs. Patients with corrected coagulopathies had fewer hemorrhagic AEs (OR, ?5.5; P = .026). The predictability was 88.2%. The area under the curve was 0.56 (95% confidence interval, 0.50–0.61).ConclusionsPreprocedural and intraprocedural RFs were identified in relation to hemorrhage with PTBD. AE risk assessment information may be valuable for prediction and management of hemorrhagic AEs.     

Factors Affecting Adverse Events after Venous Malformation Sclerotherapy

PurposeTo evaluate factors that contribute to adverse events (AEs) after embolization of venous malformations (VMs) using sclerosing agents.Materials and MethodsA retrospective review of patients who underwent direct puncture embolization of VMs with a sclerosing agent and adjunctive techniques, also termed as sclerotherapy, from 2016 to 2021 was performed. Three-hundred one embolizations in 137 patients (median age, 19.0 years; interquartile range, 12.8–31.5 years) were evaluated. The VM characteristics and embolization details were analyzed. Anticoagulation was also evaluated based on D-dimer levels. Cutaneous and noncutaneous AEs were analyzed. The AEs were categorized using Society of Interventional Radiology guidelines.ResultsVMs involving tissue planes were subcutaneous (n = 104), intramuscular (n = 84), and combined (n = 113). Overlying skin involvement was observed in 56% of the patients. Sodium tetradecyl sulfate was mainly used (83%). Periprocedural anticoagulation was used in 9% of the patients. Most AEs were minor (30/301, 9.7%), and only 1.7% (5/301) were major (21 cutaneous and 14 noncutaneous AEs). Age below 18 years (odds ratio, 4.4502; 95% confidence interval, 1.5607–12.6890; P = .0052) and overlying skin involvement (odds ratio, 7.1794; 95% confidence interval, 1.6226–31.7656; P = .0094) were factors associated with cutaneous AEs. All noncutaneous AEs developed in patients with intramuscular VMs; however, this association was not statistically significant. There was no severe hematologic AE or permanent consequence.ConclusionsThe overall AE rate after VM embolization was 11.6%; however, major AEs were rare (1.7%). Cutaneous AEs were associated with young age and overlying skin involvement. All noncutaneous AEs developed in patients with intramuscular VMs.     

Transradial versus Transfemoral Access for Patients with Liver Cancer Undergoing Hepatic Arterial Infusion Chemotherapy: Patient Experience and Procedural Complications

PurposeTo determine whether transradial access (TRA) is a more favorable and safe method for hepatic arterial infusion chemotherapy (HAIC) than transfemoral access (TFA).Materials and MethodsRetrospective and prospective cohorts of patients with liver cancer were included. Sixty-seven patients in the retrospective cohort were divided into 2 groups: (a) TRA-HAIC (n = 24) and (b) TFA-HAIC (n = 43). Another 33 patients were prospectively enrolled to receive both TRA and TFA for HAIC in a crossover design. Prolonged arterial access was required for up to 48 hours. The primary endpoint was quality of life (QOL) using the visual analog scale. The secondary endpoints mainly included procedural success, adverse events, and operation time.ResultsPatient QOL measures revealed significantly lower scores of indices in the TRA-HAIC group than in the TFA-HAIC group in the retrospective cohort (all P < .001). The significant improvement of the QOL indices by TRA-HAIC, such as overall discomfort (P = .019) and pain at the access site (P = .018), was validated in the prospective cohort. The satisfaction scores were significantly higher in the TRA-HAIC group than in the TFA-HAIC group, and patients preferred TRA-HAIC (P < .001). Radial artery occlusion (RAO) as an access-related adverse event occurred more frequently in both the retrospective and prospective cohorts (38% and 33%, P < .001 and P = .001, respectively). Notably, the multivariate analysis of RAO-associated factors showed that enoxaparin use was significantly correlated with a reduced risk of postprocedural RAO (P = .036).ConclusionsTRA was superior to TFA in patient experience. However, because of the high incidence of access-related adverse events, especially for RAO with a total incidence of 35%, strategies should be optimized for patients to benefit from TRA in future procedures.     

Endovascular Outcomes in Aortic Arch Repair with Double and Triple Parallel Stent Grafts

PurposeTo report early and midterm outcomes of treating thoracic aortic aneurysm (TAA) and aortic dissection (AD) involving zone 1 and zone 0 with multiple parallel stent grafts (PSGs).Materials and MethodsFrom February 2011 to August 2018, 31 of 1,806 patients (1.7%) who underwent thoracic endovascular aortic repair (TEVAR) with double PSGs (DPSGs) (n = 20) or triple PSGs (TPSGs) (n = 11) were retrospectively reviewed. Procedures were performed in high-risk patients who had TAA or AD involving zone 1 or zone 0.ResultsFifteen patients (48.4%) who presented with symptomatic or impending rupture underwent urgent or emergent TEVAR with DPSGs or TPSGs. Nineteen patients (61.3%) were treated for zone 0 disease. Technical and clinical success rates were 70.0% for DPSG cohort and 45.5% for TPSG cohort. Intraoperative type Ia endoleak was observed in 30% of DPSG cohort and 45.5% of TPSG cohort. One patient in the DPSG cohort died of aortic sinus rupture intraoperatively. Minor stroke during the 30-day postoperative period was more frequent in the TPSG cohort (P = .042). Mean duration of follow-up was 28.9 months ± 17.7. The TPSG cohort had a higher incidence of major adverse events (72.7% vs 25.0%, P = .021). The most common adverse events were endoleaks (12.9%), endograft migration (9.7%), PSG stenosis or occlusion (6.5%), retrograde dissection (6.5%), and stroke (3.2%). Endograft migrations were more common in TPSG cohort (27.3%, P = .037). Overall mortality rate was 16.1% (5/31) perioperatively and during follow-up. There were no statistical differences in overall survival and reintervention-free survival.ConclusionsIn the context of TEVAR with multiple PSGs for aortic arch repair, TPSGs may have a high risk of major complications.     

Comparative Outcome Analysis of N-Butyl Cyanoacrylate Embolization of the False Lumen Versus Thoracic Endovascular Aortic Repair in Aortic Dissection

PurposeTo evaluate the feasibility, safety, and effectiveness of N-butyl cyanoacrylate (NBCA) embolization for the treatment of aortic dissection.Materials and MethodsIn this single-center retrospective study conducted from February 2003 to June 2019, NBCA embolization of an aortic false lumen was attempted in 12 patients (median age, 59 y; range, 41–68 y) and thoracic endovascular aortic repair (TEVAR) was performed in 53 patients (median age, 59 y; range, 37–70 y) for aortic dissection with one or more indications of persisting pain, malperfusion, rupture or impending rupture, maximal aortic diameter ≥ 55 mm, and/or rapid aortic enlargement. The main exclusion criterion for embolization was the presence of fast blood flow in the aortic false lumen on aortography. The efficacy of NBCA embolization and TEVAR was compared by evaluating technical and clinical outcomes, repeat intervention–free survival (RFS), and overall survival (OS).ResultsTechnical success was achieved in 11 of the 12 patients treated with NBCA embolization (91.7%), and clinical success was achieved in 9 of these 11 (81.8%). No significant difference was found between embolization and TEVAR in clinical success rates (embolization, 81.8%; TEVAR, 84.9%; P = .409) or procedure-related complications (embolization, 1 patient [8.3%]; TEVAR, 4 patients [7.5%]; P = .701). In addition, embolization showed comparable 5-y RFS (embolization, 82.5% ± 9.3; TEVAR, 85.5% ± 4.8; P = .641) and 5-y OS (embolization, 100%; TEVAR, 95.4% ± 3.2; P = .744) rates to TEVAR.ConclusionsNBCA embolization of the false lumen in aortic dissection seems to be a safe and effective treatment modality for the closure of false lumen in selected patients.     

Experience with Compressed Gelfoam Plugs in Children during Liver Biopsies and Other IR Procedures: A Retrospective Single-Center Case Series

PurposeTo analyze the experience using compressed gelfoam plugs (CGPs) in children during liver biopsies and other interventional procedures.Materials and MethodsThis was a single-center, retrospective, consecutive case series of 477 various pediatric interventional radiology procedures using CGPs (January 2012 to December 2016) performed on 397 children (209 males, 188 females; median age, 7 years [range, 9 days–17.8 years]; median weight, 18 kg [range, 2.7–141 kg]). Of 477 procedures, most (n = 371) were liver biopsies, 98 were biopsies of other organs, and 8 were non-biopsy procedures. Analysis focused on liver biopsies.ResultsOf liver biopsies, a median of 2 CGPs were used per procedure, and the mean drop in hemoglobin was -0.36 g/dl (-3.0% change). Thirty-seven mild, 8 moderate, 2 severe, and 1 life-threatening (an anaphylaxis to CGP) adverse events (AEs) occurred. Analysis of liver biopsies with AEs showed significant association between number of passes, cores, and focal-type lesions (unadjusted logistic regression: P = .007, P = .022, P = .028, respectively) and age, weight, and number of passes (adjusted multiple logistic regression: P = .006, P = .032, P = .046, respectively). Technical problems relating to CGP deployment were noted in 5 (1%), without any AEs.ConclusionsCGPs were used in a wide variety of procedures and organs in children. There was 1 life-threatening AE resulting from the rare risk of anaphylaxis caused by the gelfoam-containing plug. After liver biopsies, transfusion was required in 2/371 (0.5%) procedures, 1 related to pre-biopsy anemia (0.25%).     

Thoracic Endovascular Aortic Repair for Type B Aortic Dissection Associated with Retrograde Type A Intramural Hematoma

PurposeTo evaluate feasibility and efficacy of thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD) associated with retrograde type A intramural hematoma (IMH).Materials and MethodsFrom April 2013 to January 2017, 15 consecutive patients with TBAD associated with retrograde type A IMH who underwent TEVAR were reviewed retrospectively. There was no cardiac tamponade, aortic regurgitation, involvement of coronary artery, or sign of cerebral ischemia in these patients. Enhanced CT was used in 4 patients to diagnose malperfusion of abdominal visceral arteries or lower extremity artery and underwent emergent TEVAR. For the remaining 11 patients, repeated enhanced CT after initial medical treatment within 24 hours from onset of pain showed expansion of IMH in 8 patients or presence of periaortic hematoma in 3 patients. Delayed TEVAR was scheduled for these cases.ResultsSuccessful deployment of the stent graft was achieved in all patients. There were no severe postoperative complications, such as retrograde type A aortic dissection or aortic rupture. Sudden death occurred in 1 patient 3 months after the procedure. Thrombosis of the false lumen, shrinkage of the diameter of the aorta, and complete absorption of the IMH were observed in the remaining patients at a mean follow-up of 19.8 months ± 6.57.ConclusionsTEVAR for treatment of TBAD with retrograde type A IMH is feasible and effective. It represents a treatment option for patients with TBAD associated with type A IMH with a proximal entry tear located in the descending aorta.     

Comparison between Suprapapillary and Transpapillary Uncovered Self-Expandable Metallic Stent Placement for Perihilar Cholangiocarcinoma

PurposeTo compare the effectiveness, adverse events (AEs), stent patency, and patient survival with suprapapillary and transpapillary uncovered self-expandable metallic stent placement for perihilar cholangiocarcinoma.Materials and MethodsA single-center retrospective study of 54 patients with inoperable perihilar cholangiocarcinoma who underwent percutaneous transhepatic biliary stent placement between January 1, 2019, and August 31, 2021, was conducted. According to stent location, the patients were classified into 2 groups: suprapapillary (S) and transpapillary (T). Demographic data, Bismuth-Corlette classification, type and location of the stent, laboratory data, postprocedural AEs, procedural success, stent occlusion, reintervention rate, and mortality were compared between the groups.ResultsStent placement was suprapapillary in 13 (24.1%) patients and transpapillary in 41 (75.9%) patients. Mean age was higher in Group T (78 vs 70.5 years; P = .046). Stent occlusion rates were similar in the 2 groups (Group S, 23.8%; Group T, 19.5%), as were AE rates, the most common being cholangitis (Group S, 23.1%; Group T, 24.4%). There were no significant differences in revision rate (Group S, 7.7%; Group T, 12.2%) and 30-day mortality rate (Group S, 15.4%; Group T, 19.5%). Ninety-day mortality rate was statistically significantly higher in Group T (46.3% vs 15.4%; P = .046). Preprocedural bilirubin level was higher in Group T, as were postprocedural leukocyte and C-reactive protein (CRP) levels.ConclusionsSuprapapillary and transpapillary stent placement procedures were similar in terms of procedural success, occlusion rate, revision rate, postprocedural AEs, and 30-day mortality. Ninety-day mortality rate and postprocedural leukocyte and CRP levels were higher in Group T, although these patients were also older and had higher preprocedural bilirubin levels.     

Preliminary Study of Microwave Ablation for Multifocal Papillary Thyroid Microcarcinoma in Nonoperative Candidates

PurposeTo study the feasibility, safety, and effectiveness of microwave ablation (MWA) in patients with multifocal papillary thyroid microcarcinoma (PTMC).Materials and MethodsThis retrospective study included patients who underwent MWA for multifocal PTMC (number of nodules ≤3). A total of 44 patients were included, and the mean age was 43 years (SD ± 11). After ablation, progression-free survival (PFS) at 6, 12, 24, 36, and 48 months; disease progression; change in tumor size and volume; tumor disappearance rate; and adverse events (AEs) were assessed, and the feasibility, safety, and effectiveness of MWA for PTMC were evaluated on the basis of statistical analysis.ResultsThe median follow-up period was 18 months (interquartile range, 12–33 months). The PFS rates at 6, 12, 24, 36, and 48 months were 100.0%, 96.4%, 96.4%, 70.3%, and 52.7%, respectively. The disease progression rate was 11.4% (5 of 44 patients). The maximum diameter (MD) and volume of the ablation zone were larger at the 3-month follow-up than before ablation (median MD, 13.0 vs 7.0 mm; P < .001; median volume, 503.8 vs 113.0 mm³; P < .001). Subsequently, the tumors exhibited a reduction in both size and volume after 18 months (median MD, 4.0 vs 7.0 mm; P = .04; median volume, 12.6 vs 113.0 mm³; P = .055). At the end of the follow-up period, the complete response rate was 59% (26 of 44 patients). The overall AE rate was 6.8%.ConclusionsMWA is a feasible treatment for PTMC (number of nodules ≤3), and this study preliminarily demonstrated the safety and effectiveness of this technique.     

Risk Factors Associated with Clinical Failure of Uterine Artery Embolization for Postpartum Hemorrhage

PurposeTo identify risk factors for clinical failure of uterine artery embolization (UAE) for postpartum hemorrhage (PPH), with particular attention to the uterine artery diameter.Materials and MethodsThis retrospective study included 47 patients who underwent UAE for PPH between January 1, 2010, and January 31, 2021. Technical success was defined as the completion of embolization of the arteries thought to be the cause of the bleeding. Clinical success was defined as no recurrent bleeding or need for additional therapeutic interventions. Univariate and multivariate analyses were performed to examine the risk factors associated with clinical failure of UAE.ResultsOf the 47 patients, 6 had recurrent bleeding. Of the 6 patients, 4 underwent hysterectomy, and 2 underwent repeat embolization. The clinical success rate was 87.2% (41/47), with no major adverse events such as uterine infarction or death. In univariate analysis, there were slight differences in multiparity (P = .115) and placental abruption (P = .128) and a significant difference in the findings of a narrow uterine artery on digital subtraction angiography (DSA) (P = .005). In multivariate analysis, only a narrow uterine artery on DSA was a significant factor (odds ratio, 18.5; 95% confidence interval, 2.5–134.8; P = .004).ConclusionsA narrow uterine artery on DSA was a risk factor for clinically unsuccessful UAE for PPH. It may be prudent to conclude the procedure only after it is ensured that vasospasm has been relieved.     

Dynamic Indicators That Impact the Outcomes of Thoracic Endovascular Aortic Repair in Complicated Type B Aortic Dissection

PurposeTo investigate dynamic variables obtained from retrospective computed tomography angiography for ability to predict thoracic endovascular aortic repair (TEVAR) outcomes in patients with complicated type B aortic dissection (cTBAD).Materials and MethodsSeventy-nine patients with cTBAD who received TEVAR from March 2009 to June 2018 were retrospectively enrolled. Relative true lumen area (r-TLA) was computed at the level of tracheal bifurcation every 5% of all R-R intervals. Parameters that reflect the state of intimal motion were evaluated, including difference between maximum and minimum r-TLA (D-TLA) and true lumen collapse. The endpoints comprised early (≤ 30 days) and late (> 30 days) outcomes after intervention.ResultsOverall early mortality rate was 13.9% (11/79), and early adverse events rate was 24.1% (19/79). Patients who received TEVAR within 2 days of symptom onset demonstrated the worst outcomes. A longer time of r-TLA < 25% in 1 cardiac cycle (P = .049) and larger D-TLA (P < .001) were correlated to an increased early death. In addition, D-TLA was an independent predictor of early mortality. Area under the curve of D-TLA was 0.849 (95% confidence interval 0.730–0.967) for predicting early mortality and 0.742 (95% CI 0.611–0.873) for predicting early adverse events. Survival and event-free survival rates during follow-up were decreased in the D-TLA > 21.5% group compared with the D-TLA ≤ 21.5% group (all P < .001).ConclusionsLarger D-TLA is correlated with worse postoperative outcomes and might be a crucial parameter for future risk stratification in patients with cTBAD.     

Vascular Pathology and Impact of Stent Eccentricity for Stent Restenosis in Femoropopliteal Endovascular Therapy

PurposeTo explore the clinical features associated with stent eccentricity and reveal the impact of stent eccentricity on the risk of 1-year restenosis after femoropopliteal stent implantation for symptomatic atherosclerotic peripheral artery disease (PAD).Materials and MethodsThe clinical database of a multicenter prospective study was used. It registered 2,018 limbs of 1,766 patients in whom intravascular ultrasound (IVUS)-supported femoropopliteal endovascular therapy (EVT) for symptomatic atherosclerotic PAD was planned from November 2015 to June 2017. The study included 1,233 limbs of 1,088 patients implanted with a bare nitinol stent, drug-eluting stent (DES), or stent graft and administered ≥2 antithrombotic drugs. The stent eccentricity was evaluated using IVUS, calculated as [(maximum diameter) / (minimum diameter) ? 1] at the cross-sectional segment with the lowest lumen area after stent implantation.ResultsChronic total occlusion and bilateral arterial calcification (peripheral artery calcification scoring system Grades 3 and 4) were positively associated with stent eccentricity, whereas renal failure while receiving dialysis, DES use, and stent graft use were negatively associated with stent eccentricity (all P < .05). Stent eccentricity was associated with an increased risk of 1-year restenosis (odds ratio [OR], 1.18; 95% CI, 1.01–1.37; P = .034). However, after adjustment for lesion severity and implanted stent types, the association was no longer significant (OR, 1.07; 95% CI, 0.91–1.24; P = .43).ConclusionsStent eccentricity was not significantly associated with the risk of 1-year restenosis after femoropopliteal EVT.     

The Use of an Inflatable Adhesive External Compression Device for Maintenance of Hemostasis following Angiography in Children

PurposeTo assess the safety and efficacy of the posthemostasis use of an inflatable adhesive external compression device (SafeGuard) following angiography in children performed under general anesthesia.Materials and MethodsMedical records of 74 children (43 females) with a mean age of 8.9 years (range, 0.4–18.0 years) and mean weight of 44.0 kg (range, 7.3–115.7 kg) in whom an inflatable adhesive external compression device was used for maintaining hemostasis following angiography under general anesthesia were retrospectively reviewed. After establishing hemostasis with manual compression, the device was applied and inflated over the arteriotomy. The patients were assessed for access-related adverse events in the recovery unit and during postprocedural follow-up.ResultsThe inflatable adhesive external compression device was utilized to maintain hemostasis following 181 angiography procedures. The mean length of the procedure was 396 minutes. The common femoral artery (n = 170, 93.9%) was the most common access, using 4–5-F vascular sheath (n = 118, 65.2%) or 3–5-F sheathless (n = 8, 12.7%) catheters. The mean time to deflation was 93 minutes. There were no adverse events other than minor bleeding from the arteriotomy after deflation (n = 2, 1.1%) and early deflation of the device because of pain (n = 1, <1%). Follow-up ultrasonography (n = 109 procedures, 60.2% at a mean follow-up of 2.2 years) demonstrated patency of the access artery.ConclusionsThe use of an inflatable adhesive external compression device following angiography in children to maintain hemostasis during the emergence phase of anesthesia and recovery period is safe and effective. The use of this simple device may reduce the need for postprocedural sedation and facilitate early discharge.     

Yttrium-90 Radiation Segmentectomy of Hepatocellular Carcinoma: A Comparative Study of the Effectiveness,Safety, and Dosimetry of Glass-Based versus Resin-Based Microspheres

PurposeTo evaluate the differences in safety, effectiveness, and dosimetry between glass-based and resin-based ablative yttrium-90 (⁹⁰Y) transarterial radioembolization (TARE) of hepatocellular carcinoma (HCC).Materials and MethodsUsing the modified Response Evaluation Criteria in Solid Tumors and Common Terminology Criteria for Adverse Events, both tumor response and adverse events (AEs) were assessed at 3 months after ⁹⁰Y-TARE. Post procedure ⁹⁰Y-bremsstrahlung single-photon emission computed tomography/computed tomography voxel-based dosimetry analysis was used to create tumor dose (TD) and normal tissue dose (NTD) volume histograms, and to calculate tumor particle loading and specific activity. The TD and NTD receiver operating characteristic curves evaluated the dose threshold able to predict objective (partial or complete) and complete tumor responses in addition to any-grade and grade ≥3 AE incidences. The chi-square test and Student t-test were used to assess variable differences where appropriate.ResultsBetween 2019 and 2020, 81 patients with HCC (20 in the resin-based cohort and 61 in the glass-based cohort) underwent ablative ⁹⁰Y-TARE. The resin-based cohort had more males (89% vs 65%, P = .03), lower tumor-to-normal ratio (1.81 ± 0.39 vs 2.22 ± 0.94, P = .03), higher tumor particle loading (40,172 particles/mL ± 28,039 vs 17,081 particles/mL ± 12,555, P = .0001), lower specific activity (158 Bq/particle ± 3 vs 1,058 Bq/particle ± 331, P = .001), and lower mean TD (308 Gy ± 210 vs 794 Gy ± 523, P = .0002) than the glass-based cohort. No significant differences in baseline characteristics or posttreatment AEs were noted. The overall objective and complete response rates were 85% (95% resin-based vs 82% glass-based; P = .1) and 65% (95% resin-based vs 56% glass-based; P = .003), respectively. The mean TD thresholds able to predict the objective and complete responses were 176 Gy and 247 Gy for resin-based radioembolization and 290 Gy and 481 Gy for glass-based radioembolization, respectively. A maximum NTD of 999 Gy predicted any-grade AEs in glass-based ablative ⁹⁰Y-TARE.ConclusionsCompared with glass-based ablative ⁹⁰Y-TARE, resin-based ablative ⁹⁰Y-TARE can offer comparable safety and effectiveness profiles for patients with HCC. The impact of the significantly different tumor particle loading, particle specific activities, and delivered TDs on tumor response outcomes merits further investigation.     

Comparison of Feeding-Artery-Only versus Nidus-Plus-Feeding-Artery Embolization of Pulmonary Arteriovenous Malformations

PurposeTo compare coil embolotherapy outcomes of feeding-artery-only versus nidus-plus-feeding-artery technique for treating pulmonary arteriovenous malformations (PAVMs).Materials and MethodsA total of 219 treatment-naïve PAVMs embolized in 90 patients at a single center from 2008 to 2018 met inclusion criteria for retrospective evaluation. Of the patients, 87% had a diagnosis of hereditary hemorrhagic telangiectasia (HHT). Feeding artery (FA) diameters ≥2 mm were treated. Coil embolization techniques were classified on the basis of embolic deployment zone: (i) distal feeding artery (DFA) technique (coil-to-nidus distance ≤ 1 cm) or (ii) nidus plus feeding artery (NiFA) technique. Successful embolization predictors were assessed using a multivariate linear regression model with input from patient- and PAVM-specific variables.ResultsTreatment success was achieved in 192 of 219 PAVMs (87.7%) over a mean follow-up period of 19 months. Statistically significant predictors of success in the linear regression model included simple angioarchitecture, NiFA embolization technique, and shorter follow-up duration. Stratified by technique, success rates were 99 of 105 (94.3%) and 93 of 114 (81.6%) PAVMs for NiFA and DFA, respectively (P = .007). On average, NiFA-embolized PAVMs had a larger FA diameter (3.6 mm vs 2.7 mm, P < .001) and comprised more complex PAVMs (48% vs 22%, P < .001) than DFA. Treatment success was not significantly associated with sac size or FA diameter.ConclusionsCoil embolization of both the nidus and FA was associated with a higher persistent occlusion rate than FA embolization alone.     

Custom 3-Dimensional Printed Ultrasound-Compatible Vascular Access Models: Training Medical Students for Vascular Access

PurposeTo generate 3-dimensional (3D) printed ultrasound (US)-compatible vascular models (3DPVAM) and test them for noninferiority in training medical students in femoral artery access.Materials and MethodsA 3DPVAM of normal femoral artery (FA) anatomy was developed from an anonymized computerized tomography (CT) examination. Students were randomized to a 3DPVAM or a commercial model (CM) simulation experience (SE) for US-guided FA access. Students completed a pre-SE questionnaire ranking their self-confidence in accessing the artery on a 5-point Likert scale. A standardized SE was administered by interventional radiology faculty or trainees. Students completed a post-SE questionnaire ranking comfort with FA access on a Likert scale. Student questionnaire results from the 3DPVAM group were compared with those from the CM group by using chi-square, Wilcoxon signed-rank, and noninferiority analyses.ResultsTwenty-six and twenty-three students were randomized to 3DPVAM and commercial model training, respectively. A total of 76.9% of 3DPVAM trainees and 82.6% of CM trainees did not feel confident performing FA access prior to the SE. In both groups, training increased student confidence by 2 Likert points (3DPVAM: P < 0.001; CM P < 0.001). The confidence increase in 3DPVAM trainees was noninferior to that in CM trainees (P < 0.001).ConclusionsGeneration of a custom-made 3DPVAM is feasible, producing comparable subjective training outcomes to those of CM. Custom-made 3D-printed training models, including incorporation of more complex anatomical configurations, could be used to instruct medical students in procedural skills.     

Safety of Periprocedural Antithrombotics during Pediatric Transplant Liver Biopsies

The purpose of this study was to compare the adverse event (AE) rates of percutaneous pediatric transplant liver biopsies in patients receiving periprocedural antithrombotic agents with those in patients not receiving them. A 19-year retrospective single-center study of ultrasound-guided transplant liver biopsies was conducted. Patients who received aspirin for <5 days (n = 51) or heparin <4 hours (n = 15) before biopsy were separately grouped. AEs were reported using the Society of Interventional Radiology classification. In 276 biopsy samples from patients with a mean age of 6.75 years ± 5.80, the overall AE (P = .72) and moderate AE (P = .78) rates for control and antithrombotic groups were not significantly different. No severe AEs or deaths occurred. In conclusion, aspirin continuation during percutaneous pediatric transplant liver biopsies may be safe, but more studies are necessary to confirm the safety of periprocedural heparin.     

Endobronchial Forceps Retrieval of Embedded Inferior Vena Cava Filters: Retrieval of 535 Filters at a Single Center

PurposeTo report results of 16 years of using the endobronchial forceps technique to remove embedded inferior vena cava (IVC) filters.Materials and MethodsBetween January 2005 and June 2021, 534 patients (310 women and 224 men) with a mean age of 52 years (standard deviation [SD] ± 16 years) presented for complex filter retrieval of 535 tip- or strut-embedded IVC filters. Tip-embedded filters were diagnosed on rotational venography. Filters were considered strut-embedded if they were closed-cell filters with dwell times of >6 months. The filter was dissected from the IVC using rigid bronchoscopy forceps and removed through a vascular sheath.ResultsThe endobronchial forceps technique was successful in 530 of 537 retrieval attempts on an intention-to-treat basis (98.7%); a total of 530 filters were retrieved. There were 7 failures: (a) 5 failed retrieval attempts (2 that were retrieved successfully in subsequent procedures) and (b) 2 for which retrieval was not attempted. The mean filter dwell time was 1,459 days (SD ± 1,617 days). Laser sheaths were not used for any removal. Filters included herein were 137 Celect (94 Celect and 43 Celect Platinum), 99 Günther Tulip, 72 Option (48 Option and 24 Option Elite), 68 G2, 45 G2X/Eclipse, 42 Denali, 30 OptEase, 29 Recovery, 7 Meridian, and 6 ALN with Hook filters. Thirty-four minor (6.3%) and 11 major (2%) adverse events (AEs) occurred, which did not result in permanent sequelae.ConclusionsUse of endobronchial forceps for removal of tip- and strut-embedded retrievable IVC filters is effective and has low AE rates.