Contemporary Management of Blunt Liver Trauma: An Analysis of the Trauma Quality Improvement Program Registry (2007–2019)

PurposeTo evaluate the effectiveness of management strategies for blunt liver injuries in adult patients.Materials and MethodsPatients aged ≥18 years with blunt liver injuries registered via the Trauma Quality Improvement Program (2007–2019) were identified. Management strategies initiated within 24 hours of hospital presentation were classified as nonoperative management (NOM), embolization, surgery, or combination therapy. Patients were stratified by injury grade. Linear models estimated each strategy’s effect on hospital length of stay (LOS), intensive care unit (ICU) LOS, ventilator dependence, and mortality.ResultsOf 78,127 included patients, 88.7%, 8.7%, 1.8%, and 0.8% underwent NOM, surgery, embolization, and combination therapy, respectively. Among patients with low-grade (n = 62,237) and high-grade (n = 15,890) injuries and compared with all other management strategies, NOM was associated with the shortest hospital LOS and ICU LOS. Among patients with low-grade injuries and compared with surgery, embolization was associated with a shorter hospital LOS (9.7 days; P < .001; Cohen d = 0.32) and ICU LOS (5.3 days; P < .001; Cohen d = 0.36). Among patients with high-grade injuries and compared with surgery, embolization was associated with a shorter ICU LOS (6.0 days; P < .01; Cohen d = 0.24). Among patients with low- and high-grade injuries and compared with embolization, surgery was associated with higher odds of mortality (P < .001).ConclusionsAmong patients presenting with blunt liver injuries and compared with surgery, embolization was associated with a shorter ICU LOS and lower risk of mortality.     

Clinical Results of Distal Embolization in Grade V Splenic Injury: Four-Year Experience from a Single Regional Trauma Center

PurposeTo evaluate the benefits and risks of splenic artery embolization (SAE) in patients with American Association for the Surgery of Trauma (AAST) grade V blunt spleen injury (BSI)Materials and MethodsMedical records of 88 patients treated with SAE between April 2013 and May 2017 at a regional trauma care center were reviewed retrospectively. The BSI grade according to the AAST spleen injury scale (revised version 2018) was determined by using computed tomography (CT) images. A total of 42 patients (46.6%) had AAST grade V injury and were included in the analysis. Patient demographics, angiographic findings, embolization techniques, and technical and clinical outcomes, including splenic salvage rate and procedure-related complications, were examined.ResultsSAE was performed within 2 hours after admission for 78.5% of the patients. All patients underwent selective distal embolization (n = 42). Primary clinical success rate was 80.9% (n = 34), and secondary clinical success rate was 88.1% (n = 37). The clinical failure group consisted of 5 patients. Four patients underwent splenectomy, and 1 patient died due to acute respiratory distress syndrome after embolization. The splenic salvage rate was 85.7% (n = 36). No patient had sepsis at follow-up (median, 247.0 days; interquartile range, 92.0–688.0). Clinical success rates (P = .356) and spleen salvage rates (P = .197) of patients who were hemodynamically stable (n = 19) showed no significant differences from those who were unstable (n = 23).ConclusionsDistal embolization of grade V BSI is a safe and feasible procedure which is effective for successful spleen salvage.     

Splenic Artery Embolization for Unstable Patients with Splenic Injury: A Retrospective Cohort Study

PurposeTo compare the outcomes of splenic artery embolization (SAE) for acute splenic injury (ASI) between patients who are hemodynamically stable (HDS) and hemodynamically unstable (HDU). Nonoperative management with SAE has become an accepted practice for patients who are HDS with ASI; however, SAE for the treatment of patients who are HDU with ASI has not been well studied.Materials and MethodsA retrospective cohort study was performed, including 52 patients who were HDU and HDS who underwent SAE for ASI at a Level 1 trauma center. HDU was defined as the lowest recorded systolic blood pressure prior to intervention <90 mm Hg. Utilizing the American Association for Surgery of Trauma (AAST) splenic injury scale, AAST Grades 1–3 were defined as low grade, and Grades 4–5 were defined as high grade. The primary outcomes were survival at 30 days and the need for subsequent splenectomy.ResultsSeventy-five percent (n = 39) of the patients were HDS, and 25% (n = 13) were HDU. The majority (69%) of patients who were HDU who underwent SAE did not require splenectomy, compared with 95% of patients who were HDS (P = .03). No significant difference in 30-day survival between patients who were HDU and HDS was noted. No major adverse events were recorded. There was no significant difference in 30-day patient survival or the rate of subsequent splenectomy between high-grade and low-grade splenic injuries.ConclusionsIn this retrospective cohort study, there was no statistically significant difference in the adverse events or 30-day post-SAE survival rates between patients who were HDS and HDU with ASI. The authors conclude that SAE can be a safe and effective treatment option for patients who are HDU with ASI, including high-grade splenic injury.     

Splenic Artery Embolization after Delayed Splenic Rupture Following Blunt Trauma: Is Nonoperative Management Still an Option in This Cohort?

Patients treated with splenic artery embolization (SAE) >48 hours after a blunt injury for a delayed splenic rupture (DSR) were assessed for the need for a subsequent splenectomy. Thirty-four patients underwent SAE for DSR over 10 years at our level 1 trauma center, performed at a median of 4.5 days after the injury (interquartile range = 5.5), and the patients were followed up for a median of 11 months (interquartile range = 31). There were 3 occurrences of rebleeds, and 2 patients required splenectomy (5.9%). This study showed that treatment with SAE after DSR results in splenic salvage in 94.1% of patients.     

Iatrogenic Renal Artery Injury in 90 Cases: Arteriographic Findings and Outcomes after Embolization for Bleeding

PurposeTo evaluate differences in arteriographic findings and outcomes after embolization among patients with a suspected iatrogenic renal arterial injury (IRAI).Materials and MethodsPatients at the authors’ institution who underwent renal arteriography for suspected IRAIs after partial nephrectomy, biopsy, or percutaneous access over a 20-year period were included. Records, imaging, and outcomes were reviewed. Data analysis was performed using the Fisher exact or Kruskal-Wallis test.ResultsNinety arteriograms were performed on 83 patients after partial nephrectomy (n = 32), biopsy (n = 27), or percutaneous access (n = 24), including for nephrostomy/ureterostomy and stone removal. The median number of days between the index procedure and arteriogram was highest (15 days) after partial nephrectomy and lowest (5 days) after biopsy (P = .0001). Embolization was performed during 76% of arteriograms. If prearteriographic imaging showed positive results for IRAIs, embolization was performed in 67% versus 33% if imaging showed negative results (P = .005). The transfusion rate was higher after biopsy than after partial nephrectomy or percutaneous access (P = .002). Acute kidney injury after arteriogram occurred in 7% of patients; however, all returned to baseline by 1 week.ConclusionsDespite the different mechanism of IRAIs in partial nephrectomy, biopsy, and percutaneous access, arteriographic findings and outcomes were overall similar among groups. Prearteriographic imaging can help identify IRAIs but cannot supersede the clinical judgment regarding indication for embolization. IRAIs can present acutely or after a long interim, although patients who underwent biopsy presented earlier and more frequently required a blood transfusion. IRAIs can be treated with embolization without permanent deleterious effects on renal function.     

Outcome and Distal Access Patency in Subintimal Arterial Flossing with Antegrade-Retrograde Intervention for Chronic Total Occlusions in Lower Extremity Critical Limb Ischemia

PurposeTo report the outcome and distal access patency of the Subintimal Arterial Flossing with Antegrade-Retrograde Intervention (SAFARI) technique for chronic total occlusion (CTO) in critical limb ischemia (CLI).Materials and MethodsFrom January 2009 to June 2015, 220 SAFARI procedures were performed for 200 limbs in 191 patients (108 males [56.5%]; median age, 70 years old; range, 36 to 97 years old) with CLI (9.4% were Fontaine classification 3; and 90.6% were Fontaine classification 4). Distal access was obtained from the distal superficial femoral artery (n = 6), popliteal artery (n = 49), anterior tibial artery (n = 56), dorsalis pedis (n = 51), peroneal artery (n = 12), posterior tibial artery (n = 45), and lateral plantar artery (n = 1). Distal access hemostasis was obtained with internal balloon tamponade in 71.4% (n = 157). Outcome measurements were technical success, freedom from major amputation and complications. Preprocedural angiograms of clinically driven repeat interventions were reviewed in 73 cases for distal access patency.ResultsTechnical success was achieved in 80.5% (n = 177). Reasons for technical failure include inability to obtain distal access (n = 3), cross the occlusion retrogradely (n = 16), re-enter the true lumen (n = 9), and achieve antegrade blood flow after the procedure (n = 15). Freedom from major amputation for technically successful procedures was 84.7%, 82.9%, and 81.9% at 6, 12, and 24 months, respectively. There were 3 cases of distal access bleeding with 1case that required coil embolization. The distal access remained patent in 80.8% of observable cases with repeated endovascular intervention.ConclusionsDistal retrograde arterial access (SAFARI) technique is safe and effective in the treatment of CTOs in the context of CLI, after failure of antegrade revascularization.     

A Pilot First-in-Human Study of Embrace,a Polyethylene Glycol-Based Liquid Embolic Agent,in the Embolization of Malignant and Benign Hypervascular Tumors

PurposeTo investigate the safety and efficacy of an aqueous polyethylene glycol-based liquid embolic agent, Embrace Hydrogel Embolic System (HES), in the treatment of benign and malignant hypervascular tumors.Materials and MethodsA prospective, single-arm, multicenter study included 8 patients, 5 males and 3 females, with a median age of 58.5 years (30–85 years), who underwent embolization in 8 tumors between October 2019 and May 2020. Technical success was defined as successful delivery of HES to the index vessel, with disappearance of >90% of the targeted vascular enhancement or, for portal vein embolization, occlusion of the portal branches to the liver segments for future resection. The volume of HES administered, ease of use (5 point Likert scale), administration time, and adverse events (AEs) were recorded. Evaluation was performed at 7, 30, and 90 days via clinical assessment and blood testing, and follow-up imaging was performed at 30 days.ResultsEight patients were enrolled, and 10 embolizations were performed in 8 lesions. Tumors included hepatocellular carcinoma (n = 4), renal angiomyolipoma (n = 3), and intrahepatic cholangiocarcinoma (n = 1). Technical success was 100%, and the average ease of use was 3.3 ± 1.0 SD. The HES delivery time was 1–28 minutes (median, 16.5 minutes), and the HES volume injected was 0.4–4.0 mL (median, 1.3 mL). All patients reached 30-day follow-up with imaging, and 6 patients reached 90-day follow-up. There were 3 serious AEs in 2 patients that were unrelated to the embolic agent.ConclusionHES resulted in a 100% embolization technical success rate. The product ease of use was acceptable, and no target vessel recanalization was noted on follow-up imaging at 30 days.     

Treatment Outcomes of Embolization for Peripheral Arteriovenous Malformations

PurposeTo evaluate treatment outcomes of embolization for peripheral arteriovenous malformations (AVMs) in a tertiary referral center where ethanol is the primary agent of choice.MethodsA retrospective study was performed of 93 patients (median age, 31 years; range, 2–66 years) with peripheral AVMs treated with embolization (n = 442; median, 2 per patient; range, 1–82) between January 2010 and July 2016. Ethanol was used in most cases (n = 428; 97%). AVMs were classified as type I (n = 3), type II (n = 57), type IIIa (n = 5), type IIIb (n = 15), and type IV (n = 13) according to the Yakes classification system. Effectiveness of embolization was based on AVM devascularization on angiography: 100% (total), 90%–99% (near-total), 70%–90% (substantial), 30%–70% (partial), and 0%–30% (failure). Complications were graded according to the Society of Interventional Radiology classification.ResultsIn 69% of patients, 70%–100% devascularization was achieved. Total and near-total occlusion of the nidus were more often achieved in AVMs of types I and IIIa (both 100%) than in AVMs of types II, IIIb, and IV (56%, 67%, and 39%, respectively; P = .019). A total of 109 complications were identified: 101 minor (22.9%) and 8 major (1.8%). Major complications included wounds (n = 5), false aneurysm (n = 1), finger contracture (n = 1), and severe pain (n = 1) requiring therapy. The patient complication risk was significantly affected by the number of procedures (relative risk = 2.0; P < .001). Age, AVM location, and angioarchitecture type did not significantly affect complication risk.ConclusionsAVM embolization resulted in 70%–100% devascularization in 69% of patients, with few major complications. This study indicates that the type of AVM angioarchitecture affects the number of procedures needed and the achievability of AVM devascularization.     

Cost Effectiveness of Splenic Artery Embolization versus Splenectomy after Trauma in the Netherlands

PurposeTo demonstrate that splenic artery embolization (SAE) is more cost-effective than splenectomy from a societal perspective in the Netherlands.Materials and MethodsPatient-level data obtained from the SPLENIQ study were used to populate a health economic model and were supplemented with expert opinion when necessary. Propensity score matching was used to correct for baseline differences in injury severity scores. The health economic model consisted of 3 health states (complications after intervention, SAE failure, and recovery) and a dead state. Model outcomes were incremental quality-adjusted life years (QALYs) and incremental costs of SAE over splenectomy. The Dutch health economic guidelines were followed. The model used a lifetime time horizon. Uncertainty was assessed using probabilistic sensitivity analysis and scenario analyses.ResultsPatients undergoing SAE had a higher life expectancy than patients undergoing splenectomy. Incremental QALYs were 3.1 (mostly explained by difference in life expectancy), and incremental costs were €34,135 (explained by costs related to medical consumption and lost productivity in additional life years), leading to an incremental cost-effectiveness ratio of €11,010 per QALY. SAE was considered cost-effective in >95% of iterations using a threshold of €20,000 per QALY.ConclusionsSAE results in more QALYs than splenectomy. Intervention costs for SAE are lower than that for splenectomy, but medical consumption and productivity costs in later years are higher for SAE due to better survival. SAE was found to be cost-effective compared with splenectomy under appropriate Dutch cost-effectiveness thresholds.     

Preintervention Computed Tomography Improves the Performance of Endovascular Intervention in Patients with Abdominopelvic Trauma

PurposeTo evaluate the role of computed tomography (CT) and CT angiography in guiding endovascular arteriography (EA) and embolization in hemodynamically (HD) stable and unstable patients with abdominal and/or pelvic (AP) trauma.Materials and MethodsA retrospective review was performed of patients with AP trauma who underwent EA with or without embolization (from January 2012 to August 2020) at an urban, level I trauma center. Patients aged <18 years or those undergoing EA outside of the abdomen and/or pelvis were excluded. Demographics, imaging findings, procedure length, contrast agent administration, laboratory values, and outcomes were compared on the basis of preprocedural imaging technique and hemodynamic status.ResultsA total of 190 patients with AP trauma underwent EA with or without embolization; among them, 123 were HD stable and underwent CT/CT angiography, whereas 67 were initially HD unstable and underwent operative management prior to EA. Of these patients, 38 underwent CT/CT angiography after hemodynamic stability was achieved prior to postoperative EA. The incidence of therapeutic embolization for arterial injury on EA was significantly higher in patients with preprocedural CT/CT angiography (65.8% vs 44.8%, P = .04). The positive and negative predictive values of CT angiography for arterial injury at the time of EA were 92.3% and 100%, respectively. Prior imaging was associated with a reduced contrast agent requirement at the time of EA and reduced transfusion requirement (P = .05 and P = .02). No significant differences were observed in adverse outcomes for patients undergoing preprocedural imaging.ConclusionsCT or CT angiography prior to EA for HD stable and unstable patients with AP trauma may improve the likelihood of therapeutic embolization and enable improved procedure metrics without increasing adverse outcomes.     

Changes in Modified Raymond–Roy Classification Occlusion Classes and Predictors of Recurrence-Free Survival in Patients with Intracranial Aneurysms after Endovascular Coil Embolization

PurposeTo assess changes in modified Raymond–Roy classification (MRRC) occlusion classes and recurrence rates over time and evaluate recurrence-free survival after coil embolization and its predictors.Materials and MethodsDuring 2007–2016, 201 patients (mean age, 57.1 ± 13.4 years; 75.5% women) with 240 aneurysms treated with coil embolization were enrolled. MRRC Class I (n = 210), Class II (n = 14), Class IIIa (n = 10), and Class IIIb (n =6) closures were assessed. Recurrence was defined as recanalization in MRRC Class I closures or an increase of at least 20% in any of the dimensions of the remnants of the other classes. Recurrence-free survival and its predictors were analyzed using survival analysis.ResultsMost changes in MRRC class occurred in the first year after treatment. MRRC Class I closures had a slightly lower probability of change than that associated with other classes within 1–5 years, whereas Class IIIb closures remained unchanged. Rates of recurrence or regression for all classes were highest within the first year. The median recurrence-free survival times among patients with Class IIIa and Class IIIb closures were 11.56 and 5.55 months, respectively. Significant predictors of recurrence included aneurysm size of 13–24 mm, ruptured or wide-necked aneurysms, and MRRC Class IIIa or IIIb closures.ConclusionsClass changes and recurrence rates for all MRRC classes were highest in the first year. MRRC Class IIIb closures had the highest recurrence rate and the shortest recurrence-free survival. Recurrence risk increased in Classes IIIa and IIIb and with large, ruptured or wide-necked aneurysms.     

Thermal Ablation,Embolization, and Selective Internal Radiation Therapy Combined with Checkpoint Inhibitor Cancer Immunotherapy: Safety Analysis

PurposeTo describe interventional oncology therapies combined with immune checkpoint inhibitor (ICI) therapy targeting the programmed death 1 pathway in patients with different neoplasms.Materials and MethodsThis was a retrospective cohort study of patients who underwent tumor-directed thermal ablation, embolization, or selective internal radiation therapy (SIRT) between January 1, 2011, and May 1, 2019, and received anti–programmed death 1/PD-L1 agents ≤ 90 days before or ≤ 30 days after the interventional procedure. Immune-related adverse events (irAEs) and procedural complications ≤ 90 days after the procedure were graded according to the Common Terminology Criteria for Adverse Events version 5.0. The study included 65 eligible patients (49% female; age 63 years ± 11.1). The most common tumors were metastatic melanoma (n = 28) and non–small cell lung cancer (NSCLC) (n = 12). Patients underwent 78 procedures (12 patients underwent > 1 procedure), most frequently SIRT (35.9%) and cryoablation (28.2%). The most common target organs were liver (46.2%), bone (24.4%), and lung (9.0%). Most patients received ICI monotherapy with pembrolizumab (n = 30), nivolumab (n = 22), and atezolizumab (n = 6); 7 patients received ipilimumab and nivolumab.ResultsSeven (10.8%) patients experienced an irAE (71.4% grade 1–2), mostly affecting the skin. Median time to irAE was 33 days (interquartile range, 19–38 days). Five irAEs occurred in patients with melanoma, and no irAEs occurred in patients with NSCLC. Management required corticosteroids (n = 3) and immunotherapy discontinuation (n = 1); all irAEs resolved to grade ≤ 1. There were 4 intraprocedural and 32 postprocedural complications (77.8% grade < 3). No grade 5 irAEs and/or procedural complications occurred.ConclusionsNo unmanageable or unanticipated toxicities occurred within 90 days after interventional oncology therapies combined with ICIs.     

Transcatheter Arterial Embolization in the Management of Postpartum Hemorrhage due to Genital Tract Injury after Vaginal Delivery

PurposeTo evaluate efficacy and safety of transcatheter arterial embolization (TAE) in managing postpartum hemorrhage (PPH) due to genital tract injury after vaginal delivery and to investigate factors associated with outcome of TAE.Materials and MethodsA retrospective review of 43 women (mean age, 32.6 years) who underwent TAE to manage PPH secondary to genital tract injury after vaginal delivery was performed at a single institution between January 2007 and December 2018. Clinical data and outcomes were obtained. Patients were classified into clinical success (n = 39) and failure (n = 4) groups, and comparisons between the groups were performed.ResultsThe clinical success rate of TAE for PPH due to genital tract injury was 90.7%. In the clinical failure group, transfusion volumes were higher (failure vs success: packed red blood cells, 14 pt ± 3.37 vs 6.26 pt ± 4.52, P = .003; platelets, 10.33 pt ± 4.04 vs 2.92 pt ± 6.15, P = .036); hemoglobin levels before the procedure were lower (failure vs success: 7.3 g/dL vs 10.7, P = .016). Periprocedural complications included pulmonary edema (25.6%), fever (23.3%), and pain (9.3%). Twenty-four patients were either followed for > 6 months or answered a telephone survey; 23 (95.8%) recovered regular menstruation, and pregnancy was confirmed in 11 (45.8%). Regarding fertility desires, 7 women attempted to conceive, 6 of whom (85.7%) became pregnant.ConclusionsTAE is an effective and safe method for managing PPH due to genital tract injury after vaginal delivery. Lower hemoglobin levels before the procedure and higher transfusion volumes were associated with clinical failure of TAE.     

Use of 70- to 150-μm Radiopaque Spherical Embolics for Prostatic Artery Embolization

This retrospective report describes treatment of 21 patients who underwent prostatic artery embolization using 70- to 150-μm radiopaque microspheres for lower urinary tract symptoms secondary to benign prostatic hyperplasia. Seventeen patients (81%) received successful bilateral prostatic artery embolization. At a mean follow-up of 42 days (range, 25–59 days), patients showed improvement in International Prostate Symptom Score (n = 11; mean = 10.6; P = .001), quality of life score (n = 17; mean = 2.0; P = .02), and International Index of Erectile Function (n = 17; mean = 9.3; P = .01). The mean prostate volume reduction was 28 mL (16.2%; P = .003). Nontarget embolization occurred twice, resulting in 1 minor adverse event of hematospermia.     

Where Have All the Punctures Gone? An Analysis of Thoracic Duct Embolizations

PurposeTo determine how frequently and how severely intra-abdominal structures are affected by transabdominal thoracic duct embolization (TDE).Materials and MethodsThirty-five TDE procedures in 35 patients (22 male; mean age, 57 y; age range, 10–79 y) with therapy-refractory chylous effusions were evaluated in which radiopaque embolization material outlined the access route on postinterventional CT. CT data were analyzed by 2 TDE-experienced radiologists. Abdominal structures and organs transgressed by the access route were recorded, and findings were correlated with clinical postinterventional course with follow-up of at least 44 days.ResultsIntra-abdominal structures/organs transgressed most often by the access route were the liver (n = 28), crus of the diaphragm (n = 25), pancreas (n = 14), portal vein (n = 10), duodenum (n = 7), inferior vena cava (n = 5), colon (n = 3), left renal vein (n = 2), pleura (n = 2), pericardium (n = 2), and gastric sleeve (n = 2). Pancreatitis was observed in 1 of 14 patients after pancreatic transgression. One case of clinically occult pulmonary glue migration occurred on catheter pullback through the left renal vein. Biliary peritonitis was observed after gallbladder puncture, necessitating cholecystectomy in 1 of 2 transbiliary punctures. No other relevant procedure-related complications such as hemorrhages or infectious complications were observed.ConclusionsDespite transgression of intra-abdominal structures, puncture- and access-related complications of TDE are rare. Transpancreatic manipulations are reasonably well tolerated.     

Safety and Efficacy of Peripheral Embolization with EASYX Liquid Embolic Agent: A Multicenter Prospective Study

PurposeTo evaluate the clinical safety and efficacy of EASYX, a new nonadhesive precipitating liquid embolic agent based on a polyvinyl alcohol ether polymer labeled with iodine molecules, for peripheral embolization.Materials and MethodsThis open-label prospective multicenter study was conducted on 50 consecutive patients treated with embolization using EASYX in 3 academic hospitals from April 2018 to July 2019. Indications for embolization were symptomatic varicocele (n = 15), type II endoleak (n = 8), acute hemorrhage (n = 16), portal vein embolization (PVE; n = 9), or angiomyolipoma (AML; n = 2). Patient characteristics, technical and clinical success rates, pain at injection, and satisfaction of the interventional radiologists were assessed. Follow-up imaging was performed using ultrasound for varicoceles (at 1 month) and computed tomography (CT) for the other indications (at 3 or 6 months).ResultsThe immediate technical success rate was 98%. The clinical success rates were 100% for acute hemorrhage and type II endoleaks, 89% for PVE, 86% for varicoceles, and 50% for AMLs. Patients who underwent PVE showed significant hypertrophy of the future liver remnant at follow-up (P < .001), and 55.6% of patients proceeded to hepatectomy. The absence of artifacts on imaging allowed improved monitoring of the aneurysmal sac in patients with type II endoleaks. The satisfaction rate of the interventional radiologists was >90% for 5 of 7 items.ConclusionsEASYX as a novel copolymer liquid embolic agent was safe and efficient for peripheral embolization. The absence of tantalum allowed reduced CT artifacts on imaging follow-up, which was especially useful in patients with type II endoleaks.     

Biodegradable Polydioxanone Microspheres for Transcatheter Arterial Embolization: Proof of Principle

PurposeTo evaluate feasibility, embolization success, biodegradability, reperfusion, and biocompatibility of biodegradable microspheres (MS) made from polydioxanone (PDO) for transcatheter arterial embolization.Materials and MethodsUnilateral selective renal embolization of a segmental artery was performed in 16 New Zealand White rabbits with PDO-MS (100–150 μm and 90–315 μm). Animals were randomly assigned to different observation periods and underwent control digital subtraction angiography (DSA) and MR imaging immediately (n = 3), 1 week (n = 2), 4 weeks (n = 2), 8 weeks (n = 2), 12 weeks (n = 5), and 16 weeks (n = 2) after embolization. Kidneys were harvested for macroscopic and histologic analysis of embolization success, biodegradability, and biocompatibility.ResultsEmbolization was technically successful in 15 of 16 animals. One animal died of anesthesia-related circulatory failure. The 100–150 μm MS were injected easily through 3-F catheters; the 90–315 μm MS tended to clog with intermittent catheter obstruction. DSA and MR imaging showed successful target embolization in 13 of 15 animals. In 2 animals, the entire kidney was affected owing to catheter clogging, including a reflux of MS while flushing. Control DSA and MR imaging showed increasing vascular reperfusion with time. Macroscopic and histologic analysis revealed necrosis/infarction in areas in which embolization was achieved. MS were extensively degraded after 16 weeks, and overall inflammatory reaction was mild.ConclusionsBiodegradable PDO-MS induced effective embolization of target vessels while demonstrating good biocompatibility. MS increasingly dissolved at 16 weeks, partial reperfusion started at week 1, and complete reperfusion started at week 8, thus offering possible advantages as a temporary embolic agent.     

Results from a United States Investigational Device Study of Adhesive Capsulitis Embolization in the Treatment of Shoulder Pain: The Adhesive Capsulitis Embolization Study

PurposeTo evaluate the safety and efficacy of arterial embolization to relieve shoulder pain secondary to adhesive capsulitis (AC).Materials and MethodsIn total, 20 patients (18 females, 2 males; mean age, 51 years) with AC resistant to >30 days of conservative treatment were enrolled in a multicenter prospective study. Adhesive capsulitis embolization was performed with 75-μm or 200-μm spherical particles. Subjects were assessed before and after the procedure with magnetic resonance imaging, visual analog scale (VAS; 0–100 mm) scores, Single Assessment Numeric Evaluation (SANE; 0–100) scores, and American Shoulder and Elbow Surgeons (ASES; 0–100) scores. Adverse events were recorded at all follow-up time points.ResultsHypervascularity was identified and embolization was technically successful in all patients, with 83 arteries embolized in 20 patients. Baseline VAS, SANE, and ASES scores before the procedure were 89.2 mm, 27.2, and 30.9, respectively. The 1-month (n = 19), 3-month (n = 18), and 6-month (n = 12) follow-ups demonstrated significant improvements. At the 1-month follow-up, VAS score decreased by 31.8 (P = 1.2E?11), SANE score increased by 22.1 (P = 1.8E?8), and ASES score increased by 14.2 (P = 4.3E?5). At the 6-month follow-up, VAS score decreased by 62.1 (P = 7.0E?11), SANE score increased by 55.4 (P = 4.1E?10), and ASES score increased by 44.5 (P = 1.8E?6). Due to the coronavirus pandemic, the study ended early; 6 patients did not complete the 6-month follow-up. No major adverse events were noted.ConclusionsInterim findings suggest that arterial embolization is safe and effective for patients with AC refractory to conservative treatment.     

Spontaneous Rectus Sheath Hematoma: Factors Predictive of Conservative Management Failure

PurposeTo evaluate radiographic, laboratory, and clinical factors associated with conservative management (CM) failure in spontaneous rectus sheath hematoma (RSH).Materials and MethodsRetrospective review of 72 patients with spontaneous RSH between 2006 and 2017 was performed. Patients were initially managed conservatively and then divided into 2 groups based on decision to embolize. No differences were found between embolization (n = 32) and CM (n = 40) groups in age (67.5 vs 69.5 y; P = .79), sex (31% vs 38% male; P = .58), body mass index (27.7 vs 25.7 kg/m²; P = .20), or medical comorbidities. Univariate analyses compared initial hemoglobin level, change in hemoglobin level, coagulation parameters, transfusion requirements, hematoma volume, and active extravasation on computed tomographic (CT) angiography between groups. Multivariable logistic regression identified factors predictive of CM failure. A scoring system was then created to predict CM failure.ResultsCM failed in 32 of 72 patients. Multivariable regression identified active extravasation on CT angiography (P = .02), hematoma volume (P = .01), and packed red blood cell (pRBC) transfusion of ≥ 4 U (P = .03) as predictors of embolization. A scoring system using these factors along with maximum rate of hemoglobin decrease yielded a sensitivity of 100% and specificity of 98% in determining need for embolization.ConclusionsCM for RSH was more likely to fail in patients with active extravasation on CT angiography, larger hematoma volume, pRBC transfusion of ≥ 4 U, and higher rate of hemoglobin decrease. Using these parameters, a scoring system was created that achieved high sensitivity and specificity in identifying patients who would require embolization.     

Prospective Study of Radial Artery Occlusion Following Transradial Arterial Access during IR Procedures

PurposeTo prospectively determine the rate of radial artery occlusion (RAO) in patients undergoing transradial access for intra-arterial interventions.Materials and MethodsSeventy-seven patients undergoing transradial access from August 2019 to March 2021 for 120 intra-arterial procedures (yttrium-90 mapping [n = 39] and radioembolization [n = 38], uterine artery embolization [n = 19], transarterial chemoembolization [n = 10], active bleed embolization [n = 8], angiomyolipoma embolization [n = 4], and other [n = 2]) were enrolled. The average patient age was 59 years ± 13.1 (range, 30–90 years), and 43 (55.8%) of the 77 patients were men. The patients underwent radial artery (RA) palpation, ultrasound evaluation, the Barbeau test, and the reverse Barbeau test prior to and following the intervention. Verapamil, nitroglycerin, and heparin were administered in a total of 114 (95%) of the 120 procedures prior to starting the procedure. The incidence of RAO and radial artery spasm (RAS) was calculated, and univariate logistic regression was performed to analyze the predictors of RAS.ResultsThe preprocedural RA diameter (3.0 mm ± 0.67) was not significantly different from the postprocedural RA diameter (3.0 mm ± 0.65, P = .904). The RAO rate was determined to be 0.8% (1/120), and this artery recanalized within 1 week. Due to the small number of occlusions, statistical analysis of predictors of RAO was not performed. The rate of RAS was 22.7% (27/119). None of the variables tested—including age, sex, RA diameter, initial versus repeat access, operator experience, and artery puncture technique—showed significant prediction for RAS. Patients were seen for follow-up after 111 (92.5%) of the 120 procedures.ConclusionsTransradial access resulted in a <1% rate of RAO.