Uterine Artery Embolization for Pedunculated Subserosal Fibroids: A Systematic Review and Meta-Analysis

PurposeTo provide a comprehensive overview of the literature assessing the safety and efficacy of uterine artery embolization (UAE) for patients with pedunculated subserosal fibroids.Materials and MethodsMEDLINE and Embase databases were searched without language or publication type restrictions for observational studies to estimate safety (adverse events) and efficacy (devascularization, fibroid volume reduction, and uterine volume reduction) outcomes. Case reports were included to qualitatively report adverse events. Meta-analysis was performed for single proportions and mean changes with random-effects modeling.ResultsOf 98 eligible articles, 11 studies were included in the final analysis. Of the adverse events detailed in these cases, 5 events were mild, 2 were moderate (torsion of pedunculated fibroid requiring laparoscopic myomectomy and persistent bleeding after embolization requiring hysterectomy), and 1 was severe (fibroid necrosis causing bowel obstruction requiring bowel resection and hysterectomy). There were no deaths reported in the literature. The pooled risk of adverse events was 1.7% (95% confidence interval [CI], 0.29%–9.2%; 4 of 181; I² = 0%). The pooled devascularization rate was 75.9% (95% CI, 62.4%–85.6%; 140 of 189; I² = 75%) at 3.91 months of follow-up. The percent volume reduction of the dominant pedunculated fibroid was 38.6% (95% CI, 33.0%–44.2%; I² = 0%) at 4.3 months of follow-up. The percent uterine volume reduction was 36.7% (95% CI, 30.3%–43.0%; I² = 47%) at 3.5 months of follow-up.ConclusionsUAE for pedunculated subserosal fibroids has a low risk of adverse events and effectively reduces fibroid and uterine size.     

Management of Acquired Uterine Arteriovenous Malformations Associated with Retained Products of Conception

PurposeTo evaluate the efficacy and safety of different treatments for acquired uterine arteriovenous malformations associated with retained products of conception (UAVM-RPOC) and to investigate the role of uterine artery embolization (UAE) in acquired UAVM-RPOC.Materials and MethodsThis was a retrospective study of consecutive patients who were diagnosed with uterine arteriovenous malformation by ultrasound after recently terminated pregnancy. Forty-eight patients were included in this study and were divided into 2 groups (major and minor bleeding groups) according to vaginal bleeding. The treatments were analyzed between groups. Technical and clinical success rates of UAE were analyzed.ResultsOf the 48 patients, 11 patients were in the massive bleeding group and 37 were in the minor bleeding group. Five patients were referred for UAE in each group and UAE was a priority for patients with unstable hemodynamics (chi-square value = 5.524, P =.022). Conservative management, dilation and curettage (D&C), operative hysteroscopy, and UAE were performed in 16 (33%), 18 (38%), 7 (15%), and 13 (27%) patients, respectively. Two patients with ectopic pregnancies suffered uncontrollable bleeding during D&C and required emergent UAE. Three patients underwent UAE before surgery to prevent hemorrhage. The technical and clinical success rates of UAE were 100%. No complications or recurrences occurred.ConclusionsUAE is a safe and effective treatment for UAVM-RPOC and a priority for patients with unstable hemodynamics. Conservative management, D&C, and hysteroscopy are safe and effective for patients with UAVM-RPOC with stable hemodynamics. However, UAVM-RPOC following ectopic pregnancy may have high risks of massive hemorrhage during procedures.     

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.     

Utilization of Endovascular and Surgical Treatments for Symptomatic Uterine Leiomyomas: A Population Health Perspective

PurposeTo conduct a population-level analysis of surgical and endovascular interventions for symptomatic uterine leiomyomata by using administrative data from outpatient medical encounters.Materials and MethodsBy using administrative data from all outpatient hospital encounters in California (2005–2011) and Florida (2005–2014), all patients in the outpatient setting with symptomatic uterine leiomyomata were identified. Patients were categorized as undergoing hysterectomy, myomectomy, uterine artery embolization (UAE), or no intervention. Hospital stay durations and costs were recorded for each encounter.ResultsA total of 227,489 patients with uterine leiomyomata were included, among whom 39.9% (n = 90,800) underwent an intervention, including hysterectomy (73%), myomectomy (19%), or UAE (8%). The proportion of patients undergoing hysterectomy increased over time (2005, hysterectomy, 53.2%; myomectomy, 26.9%; UAE, 18.0%; vs 2013, hysterectomy, 80.1%; myomectomy, 14.4%; UAE, 4.0%). Hysterectomy was eventually performed in 3.5% of patients who underwent UAE and 4.1% who underwent myomectomy. Mean length of stay following hysterectomy was significantly longer (0.5 d) vs myomectomy (0.2 d) and UAE (0.3 d; P < .001 for both). The mean encounter cost for UAE ($3,772) was significantly less than those for hysterectomy ($5,409; P < .001) and myomectomy ($6,318; P < .001). Of the 7,189 patients who underwent UAE during the study period, 3.5% underwent subsequent hysterectomy.ConclusionsThe proportion of women treated with hysterectomy in the outpatient setting has increased since 2005. As a lower-cost alternative with a low rate of conversion to hysterectomy, UAE may be an underutilized treatment option for patients with uterine leiomyomata.     

Management of Symptomatic Vascularized Retained Products of Conception by Proximal Uterine Artery Embolization with Gelatin Sponge Torpedoes

PurposeTo evaluate the effectiveness and safety of temporary proximal uterine artery embolization (UAE) for the treatment of highly vascularized retained products of conception (RPOCs).Materials and MethodsThis retrospective analysis included women who underwent treatment for vaginal bleeding after abortion, miscarriage, or delivery, with highly vascularized RPOCs detected by Doppler ultrasound (US) (ie, presence of an enhanced myometrial vascularity, a low resistance index of <0.5, and a peak systolic velocity of ≥0.7 m/s). A unilateral or bilateral embolization with torpedoes of gelatin foam was performed. From November 2017 to January 2021, 24 women with a median age of 30 years (interquartile range, 26.0–34.5 years) with symptomatic highly vascularized RPOCs were included. Clinical success was defined as bleeding arrest between the UAE and 1-month follow-up. Technical success was defined as the complete obstruction of at least 1 uterine artery supplying vascular abnormalities. The safety of the procedure according to the classification of the Society of Interventional Radiology and evolution of lesions on US were also reported.ResultsTechnical success was achieved in all 24 (100%) patients, with bilateral arterial embolization in 19 (79%) patients and unilateral embolization in 5 (21%) patients. Clinical success was achieved in all 24 (100%) patients. Five patients still had uterine retention at the 1-month follow-up, including 2 patients with highly vascularized RPOCs. Two patients benefited from hysteroscopy, and 3 had noninvasive management. Four minor adverse events were reported (1 patient had infectious endometritis and 3 patients had a postembolization syndrome).ConclusionsProximal UAE with torpedoes of gelatin foam is safe and effective for the management of symptomatic highly vascularized RPOCs.     

Utilization and Comparative Effectiveness of Uterine Artery Embolization versus Hysterectomy for Severe Postpartum Hemorrhage: A National Inpatient Sample Study

PurposeTo identify differences in mortality or length of hospital stay for mothers treated with uterine artery embolization (UAE) or hysterectomy for severe postpartum hemorrhage (PPH), as well as to analyze whether geographic or clinical determinants affected the type of therapy received.Materials and MethodsThis National Inpatient Sample study from 2005 to 2017 included all patients with live-birth deliveries. Severe PPH was defined as PPH that required transfusion, hysterectomy, or UAE. Propensity score weighting–adjusted demographic, maternal, and delivery risk factors were used to assess mortality and prolonged hospital stay.ResultsOf 9.8 million identified live births, PPH occurred in 31.0 per 1,000 cases. The most common intervention for PPH was transfusion (116.4 per 1,000 cases of PPH). Hysterectomy was used more frequently than UAE (20.4 vs 12.9 per 1,000 cases). The following factors predicted that hysterectomy would be used more commonly than UAE: previous cesarean delivery, breech fetal position, placenta previa, transient hypertension during pregnancy without pre-eclampsia, pre-existing hypertension without pre-eclampsia, pre-existing hypertension with pre-eclampsia, unspecified maternal hypertension, and gestational diabetes (all P < .001). Delivery risk factors associated with greater utilization of hysterectomy over UAE included postterm pregnancy, premature rupture of membranes, cervical laceration, forceps vaginal delivery, and shock (all P < .001). There was no difference in mortality between hysterectomy and UAE. After balancing demographic, maternal, and delivery risk factors, the odds of prolonged hospital stay were 0.38 times lower with UAE than hysterectomy (P < .001).ConclusionsDespite similar mortality and shorter hospital stays, UAE is used far less than hysterectomy in the management of severe PPH.     

Intra-Arterial Lidocaine Administration for Anesthesia after Uterine Artery Embolization with Trisacryl Gelatin Microspheres for Leiomyoma

PurposeTo evaluate whether administration of lidocaine into the uterine artery for anesthesia immediately after uterine artery embolization (UAE) with trisacryl gelatin microspheres (TAGM) for leiomyoma is safe and effective.Materials and MethodsIn a single-institution retrospective study, 100 patients underwent UAE using TAGM with a pruned tree endpoint between June 2014 and April 2019. The first 50 patients (control group) underwent UAE without lidocaine; in the second 50 patients (study group), lidocaine was administered into the uterine artery immediately after UAE. Baseline characteristics and technical and periprocedural outcomes were compared. Visual analog scale (VAS) scores 0, 3, 6, 9, 12, and 18 hours after UAE were compared between the groups with repeated measures analysis of variance. Each multivariate-adjusted VAS score < 24 hours was compared with analysis of covariance.ResultsNo significant differences were observed in baseline characteristics or technical and periprocedural outcomes, including the volume of morphine used (P = .415), between the groups. No significant differences were found in crude or multivariate-adjusted VAS scores at each time point < 24 hours. Only the multivariate-adjusted VAS score 3 hours after UAE was 0.7 lower in the study group (mean ± SE, 2.2 ± 0.3 vs 2.9 ± 0.3); however, no significant difference was noted (P = .070). No adverse events associated with lidocaine were detected.ConclusionsIntra-arterial lidocaine administration immediately after UAE with TAGM for leiomyoma was safe, but did not contribute to significant reductions in pain or volume of narcotic agent administered.     

Feasibility of Transtibial Access for Uterine Artery Embolization

Ten women with a mean body mass index of 31.5 kg/m² and symptomatic uterine pathology underwent uterine artery embolization (UAE) via transtibial access (TTA). Nine out of 10 UAEs were successfully performed via TTA, with 2 minor adverse events. Outpatients with leiomyomas had stable to improved symptoms at follow-up; hospitalized patients with abnormal uterine bleeding from malignant tumors or arteriovenous malformations were discharged shortly after UAE with the cessation of hemorrhage. TTA is a feasible alternative for UAE for patients with obesity, diminutive radial arteries, or atherosclerosis that may confer an added risk of rare neurologic adverse events from transradial access.     

Evaluation of the Effect of Routine Antibiotic Administration after Uterine Artery Embolization on Infection Rates

PurposeTo evaluate the effect of routine administration of post-procedural antibiotics following elective uterine artery embolization (UAE) on infectious complication rates.Materials and MethodsThe charts of patients who underwent UAE between January 2013 and September 2019 were retrospectively reviewed. Prior to January 15, 2016, all patients received post-procedural antibiotics with 500 mg of ciprofloxacin twice a day orally for 5 days. After January 15, 2016, none of the patients received post-procedural antibiotics. All patients in both groups received pre-procedural intravenous antibiotics. The post-procedural antibiotics group included 217 patients (age, 44.7 ± 6 years); the no-antibiotics group included 158 patients (age, 45.4 ± 5.6 years). Patients in the no-antibiotics group had a significantly higher rate of diabetes mellitus (P = .03) but fewer cases of adenomyosis (P = .048). Otherwise, demographic and fibroid characteristics were similar between the groups.ResultsSix infectious complications (6/375, 1.6%) were recorded. No statistically significant difference (P = .66) was observed in the number of infections between the post-procedural antibiotics group (4/217, 1.8%) and the no-antibiotics group (2/158, 1.3%). Three of the 6 infectious complications presented with malodorous vaginal discharge (3/375, 0.8%) and received nominal therapy. The 3 remaining complications (0.8%) were considered major and included 2 patients (0.5%) who underwent hysterectomy and 1 patient (0.3%) who underwent myomectomy. The major infection rate was 0.9% (2/217) in the post-procedural antibiotics group and 0.7% (1/158) in the no-antibiotics group (P = 1). There were no 90-day post-procedural mortalities.ConclusionsDiscontinuation of routine post-procedural antibiotics with ciprofloxacin after elective UAE did not result in increased rates of infectious complications within the first 90 days post procedure.     

Deep Learning Based on MR Imaging for Predicting Outcome of Uterine Fibroid Embolization

PurposeTo develop and validate a deep learning model based on routine magnetic resonance (MR) imaging obtained before uterine fibroid embolization to predict procedure outcome.Materials and MethodsClinical data were collected on patients treated with uterine fibroid embolization at the Hospital of the University of Pennsylvania from 2007 to 2018. Fibroids for each patient were manually segmented by an abdominal radiologist on a T1-weighted contrast-enhanced (T1C) sequence and a T2-weighted sequence of MR imaging obtained before and after embolization. A residual convolutional neural network (ResNet) model to predict clinical outcome was trained using MR imaging obtained before the procedure.ResultsInclusion criteria were met by 727 fibroids in 409 patients. At clinical follow-up, 85.6% (n = 350) of 409 patients (590 of 727 fibroids; 81.1%) experienced symptom resolution or improvement, and 14.4% (n = 59) of 409 patients (137 of 727 fibroids; 18.9%) had no improvement or worsening symptoms. The T1C trained model achieved a test accuracy of 0.847 (95% confidence interval [CI], 0.745–0.914), sensitivity of 0.932 (95% CI, 0.833–0.978), and specificity of 0.462 (95% CI, 0.232–0.709). In comparison, the average of 4 radiologists achieved a test accuracy of 0.722 (95% CI, 0.609–0.813), sensitivity of 0.852 (95% CI, 0.737–0.923), and specificity of 0.135 (95% CI, 0.021–0.415).ConclusionsThis study demonstrates that deep learning based on a ResNet model achieves good accuracy in predicting outcome of uterine fibroid embolization. If further validated, the model may help clinicians better identify patients who can most benefit from this therapy and aid clinical decision making.     

Uterine Artery Embolization in the Twentieth Week of Pregnancy in Abnormally Invasive Placenta with Live Birth

An abnormally invasive placenta is an increasing and potentially life-threatening pregnancy complication. The case presented herein is a heterotopic dichorial pregnancy with implantation of 1 placenta within the isthmocervical area, which caused vaginal bleeding during the 20th week of pregnancy, requiring a blood transfusion. To stop the bleeding, a bilateral embolization of the cervical branches of the uterine arteries was performed. The embolization was well tolerated and resulted in the abrupt and lasting cessation of bleeding for more than 10 weeks, resulting in the live birth of 1 child.     

Uterine Artery Embolization following Cesarean Delivery but prior to Hysterectomy in the Management of Patients with Invasive Placenta

PurposeTo evaluate outcomes of patients with placenta accreta spectrum (PAS) disorders who underwent uterine artery embolization (UAE) following cesarean delivery but before hysterectomy.Materials and MethodsA retrospective review of patients with PAS treated with cesarean-hysterectomy (C-hyst) was performed. Patients in the UAE group underwent UAE after cesarean delivery but before hysterectomy; patients in the control group underwent C-hyst alone. Estimated blood loss (EBL), transfusion requirements, length of intensive care unit (ICU) stay, and adverse events were evaluated.ResultsThe study included 31 patients, 7 in the UAE group and 24 in the control group. Median EBL, transfusion requirements, and length of ICU stay in the UAE group compared with control group were 1,500 mL (range, 500–2,000 mL) vs 2,000 mL (range, 1,000–4,500 mL) (P = .04), 150 mL (range, 0–650 mL) vs 550 mL (range, 0–3,125 mL) (P = .10), and 0 d (range, 0–1 d) vs 0.5 d (range, 0–2 d) (P = .07). All patients in the UAE group had placenta increta; patients in the control group had placenta accreta (29%), increta (54%), and percreta (17%) (P = .10). Subgroup analysis of patients with placenta increta demonstrated that the UAE group had a significant decrease in median EBL (P = .004), transfusion requirements (P = .009), and length of ICU stay (P = .04). No adverse events following UAE were noted.ConclusionsUAE following cesarean delivery but before hysterectomy in patients with placenta increta appears to be safe and effective in decreasing EBL, transfusion requirements, and length of ICU stay compared with C-hyst alone.     

Timing of Uterine Artery Embolization for Leiomyoma during the Menstrual Cycle

PurposeTo investigate differences in outcomes of uterine artery embolization (UAE) for leiomyoma when performed during different phases of the menstrual cycle.Materials and MethodsIn this single-institution retrospective analysis, 111 premenopausal patients (median [range] age, 44 [33–52] years) undergoing UAE for symptomatic leiomyoma between June 2014 and February 2020 were included. Twenty-one patients underwent UAE in the menstrual phase (the early follicular phase), 27 in the late follicular phase, and 63 in the luteal phase. Baseline characteristics and technical and peri-procedural outcomes were compared among groups. Leiomyoma infarction on contrast-enhanced magnetic resonance imaging 1 week after UAE and 4-month outcomes, including changes in the Uterine Fibroid Symptom and Quality of Life questionnaire scores, the volume reduction rates of the uterus and largest leiomyoma, follicle stimulating hormone values, adverse events, and amenorrhea, were compared among groups.ResultsA 4-month follow-up was completed for all patients. No significant differences were observed among groups in baseline characteristics or technical and peri-procedural outcomes. There were no significant differences in the multivariate-adjusted 1-week infarction rates of all leiomyoma volumes (P = .161) or multivariate-adjusted 4-month outcomes, including changes in the Uterine Fibroid Symptom and Quality of Life questionnaire symptoms and total scores (P = .864 and P = .798, respectively), the volume reduction rates of the uterus and the largest leiomyoma (P = .865 and P = .965, respectively), and follicle stimulating hormone values (P = .186) among the groups. No significant differences were noted in the 4-month adverse events (P = .260) or amenorrhea (P = .793) among the groups.ConclusionsThe present study demonstrated no significant differences in the outcomes of UAE for leiomyoma when performed during different phases of the menstrual cycle.     

Superior Hypogastric Nerve Block for Pain Control after Uterine Artery Embolization: Effect of Addition of Steroids on Analgesia

Superior hypogastric nerve block (SHNB) decreases pain and use of narcotic pain medication following uterine artery embolization (UAE). The purpose of this retrospective study was to evaluate the effect of the addition of a corticosteroid (triamcinolone) to SHNB on analgesia following UAE. Records of 16 patients were reviewed for when pain occurred or acutely worsened after the procedure. No major complications were identified. Patients reported that pain began or worsened an average of 33.8 hours after the procedure, when their average pain increased from 0.6/10 to 5.9/10 (P < .001). This suggests that addition of triamcinolone to SHNB could result in prolonged analgesia following UAE.     

Transcatheter Arterial Embolization for Benign Chronic Inflammatory Joint Pain: A Systematic Review and Meta-Analysis

PurposeTo evaluate the efficacy and safety of transcatheter arterial embolization (TAE) for the treatment of chronic inflammatory joint pain via systematic review and meta-analysis.Materials and MethodsMEDLINE and EMBASE databases were searched for studies reporting outcomes in patients with chronic inflammatory joint pain treated with TAE. Meta-analyses of pain score changes, changes in proportions of patients on analgesic medications, range of motion changes, technical success rates, and adverse events rates were performed. Subgroup analyses were conducted with respect to pain site (knee versus shoulder).ResultsFourteen observational studies, which included 346 patients, were reviewed. The pooled technical success rate was 95.8%, and no major adverse events were observed. The pooled mean difference in pain score at 1 week was 3.1. At 1, 3, and 6 months, the difference in score was 4.0, 4.2, and 5.1, respectively. At 1 year, the difference was 5.5. Subgroup analysis demonstrated that shoulder embolization was associated with greater reduction of pain than knee embolization at 3 and 6 months (P < .001 and P = .018, respectively), whereas there was no significant difference between the sites at 1 month (P = .734). The pooled proportions of patients on analgesic medication at baseline and at 1, 3, 6, and 12 months were 81.1%, 36.3%, 42.3%, 28.2%, and 22.4%, respectively. The pooled estimated increase in the range of motion among patients who underwent shoulder embolization was 55.6° for anterior elevation and 64.7° for abduction.ConclusionsTAE is an effective and safe therapeutic option for patients with chronic inflammatory joint pain.     

Below-the-Ankle Angioplasty in Patients with Critical Limb Ischemia: A Systematic Review and Meta-Analysis

PurposeTo evaluate the safety and effectiveness of below-the-ankle (BTA) angioplasty and to assess whether additional BTA angioplasty after below-the-knee (BTK) angioplasty would improve clinical outcomes in patients with critical limb ischemia.Materials and MethodsTwo authors independently performed the search, study selection, assessment of methodological quality, and data extraction for this systematic review and meta-analysis. MEDLINE, Embase, and the Cochrane Database of Systematic Reviews were searched. Articles were eligible if it was reported that BTA angioplasty was performed and if the articles were published in English and had the full text available. Methodological quality was assessed using the Methodological Index for Non-Randomized Studies (MINORS) score. The primary outcome was 12-month limb salvage rate. Secondary outcomes were 12-month amputation-free survival, technical success, complications, survival, and freedom from reintervention.ResultsTen articles met the inclusion criteria, reporting a total of 478 patients with BTA angioplasty performed in 524 legs. Three of the 10 included studies compared BTK angioplasty only to BTK angioplasty and additional BTA angioplasty. The pooled 12-month limb salvage rate was 92% (95% confidence interval [CI], 0.88–0.96). No statistically significant difference was found in limb salvage when additional BTA angioplasty was compared to BTK angioplasty only (odds ratio [OR], 1.23; 95% CI, 0.61–2.49). The pooled 12-month amputation-free survival was 78% (95% CI, 0.69–0.87). No statistically significant difference was found in amputation-free survival rate when additional BTA angioplasty was compared to BTK angioplasty only (OR, 1.58; 95% CI, 0.95–2.64). The methodological quality of the studies included was moderate, according to the MINORS score.ConclusionsThis systematic review and meta-analysis showed that additional BTA angioplasty is a safe and feasible procedure, with a 92% pooled proportion of limb salvage at 12 months.     

Middle Meningeal Artery Embolization with Liquid Embolic Agents for Chronic Subdural Hematoma: A Systematic Review and Meta-analysis

PurposeTo assess the efficacy and safety of middle meningeal artery (MMA) embolization with liquid embolic agents and the outcomes of patients following this procedure.Materials and MethodsA review of the literature was conducted to identify studies investigating the efficacy and safety of MMA embolization with liquid embolic agents in patients with chronic subdural hematoma (cSDH) in PubMed, Scopus, Embase, and Web of Science. The keywords “liquid embolic agent,” “middle meningeal artery,” “cSDH,” and “embolization” as well as their synonyms were used to build up the search strategy. The R statistical software and random-effects model were used for analysis. Heterogeneity was reported as I², and publication bias was calculated using the Egger test.ResultsOf 628 articles retrieved, 14 studies were eligible to be included in this study. Data of 276 patients were analyzed. n-Butyl cyanoacrylate and ethylene vinyl alcohol copolymer were the most commonly used embolic agents. This study revealed a pooled mortality rate of 0% (95% confidence interval [CI], 0.00%–100%), recurrence and failure rate of 3% (95% CI, 1%–10%), reoperation/reintervention rate of 4% (95% CI, 2%–12%), rate of size decrease of 94% (95% CI, 79%–98%), technical success rate of 100% (95% CI, 76%–100%), and adverse event rate of 1% (95% CI, 0.00%–4%).ConclusionsWith low mortality, recurrence, reoperation, and adverse event rates and a remarkable decrease in the size of hematomas, MMA embolization with liquid embolic agents may be considered a safe and effective treatment option in patients in whom surgical intervention has previously failed and as an alternative to conventional treatments.     

Machine Learning Offers Exciting Potential for Predicting Postprocedural Outcomes: A Framework for Developing Random Forest Models in IR

PurposeTo demonstrate that random forest models trained on a large national sample can accurately predict relevant outcomes and may ultimately contribute to future clinical decision support tools in IR.Materials and MethodsPatient data from years 2012–2014 of the National Inpatient Sample were used to develop random forest machine learning models to predict iatrogenic pneumothorax after computed tomography–guided transthoracic biopsy (TTB), in-hospital mortality after transjugular intrahepatic portosystemic shunt (TIPS), and length of stay > 3 days after uterine artery embolization (UAE). Model performance was evaluated with area under the receiver operating characteristic curve (AUROC) and maximum F1 score. The threshold for AUROC significance was set at 0.75.ResultsAUROC was 0.913 for the TTB model, 0.788 for the TIPS model, and 0.879 for the UAE model. Maximum F1 score was 0.532 for the TTB model, 0.357 for the TIPS model, and 0.700 for the UAE model. The TTB model had the highest AUROC, while the UAE model had the highest F1 score. All models met the criteria for AUROC significance.ConclusionsThis study demonstrates that machine learning models may suitably predict a variety of different clinically relevant outcomes, including procedure-specific complications, mortality, and length of stay. Performance of these models will improve as more high-quality IR data become available.     

Image-Guided Percutaneous Ablation of Adrenal Metastases: A Meta-Analysis of Efficacy and Safety

PurposeTo evaluate the efficacy and safety of percutaneous ablation of adrenal metastases through a meta-analysis of various image-guided percutaneous ablation techniques.Materials and MethodsA comprehensive literature search of PubMed and Embase databases was performed for studies evaluating the efficacy and/or safety of image-guided percutaneous ablation of adrenal metastases. A total of 37 studies published between 2009 and 2020 were analyzed, comprising a sample size of 959 patients. Proportion estimates of overall survival, local control, and toxicity were analyzed in a pooled meta-analysis. The pooled prevalence of adverse events after ablation was calculated based on common terminology criteria for adverse events (CTCAE) grading.ResultsOf the 959 included patients, 320 (33.3%) underwent radiofrequency ablation, 72 (7.5%) microwave ablation, 95 (9.9%) cryoablation, and 46 (4.8%) ethanol injections for treatment of adrenal metastases. The remaining 426 (44.4%) patients were from studies involving a mixture of the 4 listed percutaneous ablation techniques. The pooled 1-year local control rate was 80% (95% confidence interval [CI], 76%–83%). The pooled 1-year overall survival rate was 77% (95% CI, 70%–83%). The overall rate of severe adverse events after ablation (CTCAE grade 3 or higher) was 16.1%. The overall rate of low-grade adverse events after ablation (CTCAE grade 2 or lower) was 32.6%. Approximately 21.9% (n = 203) of patients experienced intraprocedural hypertensive crises, the majority of which were reversed with antihypertensive medications.ConclusionsThis study demonstrates that image-guided percutaneous ablation can be effective in achieving acceptable short- to mid-term local tumor control and overall survival with a moderate safety profile.