Type II Endoleak Nidus Volume on Arterial and Delayed Phases of Initial CT Angiography after Endovascular Abdominal Aortic Aneurysm Repair Predicts Persistent Endoleak and Aneurysm Sac Enlargement.

PURPOSE: To evaluate type II endoleak nidus volume (ENV) in the arterial phase (ENVAP) and delayed phase (ENVDP) of the first postoperative CT angiography (CTA) as a predictor of persistent endoleak and aneurysm sac enlargement at follow-up CTA in patients with endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm. MATERIALS AND METHODS: Ninety-three patients (mean age ± standard deviation, 72 years ± 8; range, 56-88 years) with EVAR and type II endoleak were included in a single-institution retrospective study conducted between March 1, 2005, and December 31, 2018. ENVAP, ENVDP, change of volume (ENVDP-AP), and percentage of ENVAP and ENVDP in aneurysm sac volume (ASV) (ENVAP/ASV%, ENVDP/ASV%, respectively) were measured on first postoperative CTA images. The mean follow-up was 31.6 months ± 26.6 (range, 6-163.8 months). Patients were divided into two groups (group A, spontaneous resolution of endoleak without intervention [n = 29] and group B, persistent endoleak at follow-up CTA [n = 64]) and compared by using the Mann-Whitney U, Wilcoxon signed rank, and Pearson χ2 tests. Receiver operating characteristic (ROC) analysis was used to compare accuracies of parameters at first postoperative CTA. RESULTS: The accuracy of ENVDP (area under the ROC curve [AUC], 0.78) was superior to the accuracy of ENVDP/ASV% (AUC, 0.76), ENVDP-AP (AUC, 0.74), ENVAP (AUC, 0.71), and ENVAP/ASV% (AUC, 0.69) in indicating persistent endoleak. In group B, 46 patients (72%) showed ASV enlargement and 44 patients (69%) underwent endoleak embolization. ENVAP (1.7 cm3 ± 2.9 vs 3.4 cm3 ± 4.2; P = .001), ENVDP (2.9 cm3 ± 3.8 vs 8.0 cm3 ± 9.6; P < .001), ENVDP-AP (1.1 cm3 ± 1.8 vs 4.5 cm3 ± 7.8; P < .001), ENVAP/ASV% (0.9% ± 1.5 vs 1.7% ± 2.2; P = .003), and ENVDP/ASV% (1.6% ± 2.2 vs 3.7% ± 3.6; P < .001) were smaller in group A than in group B. CONCLUSION: ENVDP of the first postoperative CTA is an accurate predictor of persistent endoleak compared with ENVAP, and persistent endoleak is associated with aneurysm sac enlargement, in which earlier intervention is recommended.© RSNA, 2021.

Embolization of uterine arteriovenous malformation causing postpartum hemorrhage using n-butyl cyanoacrylate: A case report.

Uterine artery arteriovenous malformations (AVMs) are rare anomalies that may result in uterine hemorrhage. A 40-year-old G8P5126 woman presented with severe vaginal bleeding and an estimated 2000 mL of blood loss at home. Three weeks prior, she had a vaginal delivery of a term infant resulting in post-partum hemorrhage, with 2700 mL of blood loss. The patient had a history of ectopic pregnancy, placenta previa, and dilatation and curettage. Interventional radiology was consulted, and the patient underwent angiography of the internal iliac and uterine arteries revealing the presence of a uterine AVM, which was successfully embolized using a thick mixture of n-butyl cyanoacrylate and lipiodol. The patient experienced no further episodes of bleeding and was discharged within 24 hours. Recognition of typical symptoms and risk factors for uterine arteriovenous malformations can facilitate early diagnosis and appropriate treatment.

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.

CT-Guided Percutaneous Drainage Catheter Placement in the Abdomen and Pelvis: Predictors of Outcome and Protocol for Follow-up.

PURPOSE: To determine predictors of outcomes for patients who undergo computed tomography (CT)-guided percutaneous abdominal or pelvic drainage catheter placement and to identify which patients benefit from fluoroscopic drainage catheter interrogation (abscessogram). MATERIALS AND METHODS: A retrospective review of 383 patients (mean, 52 years old; range 8-89 years old; 158 males: 225 females) who underwent 442 CT-guided procedures and 489 catheter placements for fluid collections in the abdomen or pelvis from January 1, 2015, to December 31, 2016 was performed. Variables including underlying disease, fluid location, number of collections drained, number of catheter exchanges and follow-up abscessograms performed, catheter size, and fistula detection were analyzed to determine factors associated with fistula formation and increased catheter dwell time. RESULTS: A single abscessogram followed by catheter removal was performed for 217 catheters (44%). An increased number of abscessograms was significantly associated with drainage catheter size (P < .001) and presence of a fistula (P < .001). Fistulae were detected in 95 cases (19%) and were significantly associated with an increased number of drain exchanges (P < .001) and an underlying diagnosis of Crohn's disease (P = .02). Based on these data, a clinical algorithm for drain management is presented. CONCLUSIONS: Abscessograms performed after CT-guided percutaneous drainage catheter placement are useful to detect catheter malposition, occluded catheters, and fistulae but are not necessary for all patients. If performed selectively, particularly in patients with an underlying diagnosis of Crohn's disease or those at high risk for developing fistulae, unnecessary examinations can be avoided, reducing cost, extra hospital visits, and radiation dose.

Initial Experience with Balloon-Occlusion Prostatic Artery Embolization.

Twelve patients underwent balloon-occlusion prostatic artery embolization (PAE) at a single center. Bilateral prostatic artery catheterization was achieved in all patients, but unilateral embolization was performed in 1 patient as a result of the presence of a prostatic arteriovenous fistula. Mean International Prostate Symptom Score and quality-of-life score decreased by 15 ± 7 (P < .01) and 4 ± 1 (P < .01) points, respectively, over a mean follow-up period of 22 weeks ± 8. Only self-limiting minor complications were encountered. The initial experience with balloon-occlusion PAE suggests that it is technically feasible and can be performed safely.

Incidence and Clinical Significance of Renal Infarct After Fenestrated Endovascular Aortic Aneurysm Repair.

OBJECTIVE: The purpose of this study is to determine the incidence and clinical significance of renal infarcts after fenestrated endovascular aortic aneurysm repair (FEVAR). MATERIALS AND METHODS: All patients who underwent FEVAR with unenhanced and contrast-enhanced CT angiography during a 4-year period were retrospectively reviewed. Two staff radiologists reviewed pre- and post-FEVAR CT examinations for the presence of renal infarcts. Pre- and postoperative serum creatinine levels were examined to determine statistical significance. The incidence of renal infarct and percentage of renal volume reduction were calculated. RESULTS: Ninety patients were included for analysis. All patients had a mild progressive increase in serum creatinine level after FEVAR. Twenty-three patients (26%) had a renal infarct identified on post-FEVAR CT, nine (39%) of which were secondary to intentional exclusion of an accessory renal artery and 14 (61%) of which were presumed to be embolic. Two patients with presumed embolic infarcts and three with exclusion of an accessory renal artery had an increase in serum creatinine level of greater than 0.3 mg/dL at 1 month after FEVAR. CONCLUSION: Although renal infarcts are common after FEVAR, the clinical relevance of these events appears to be limited, with less than one-quarter of patients with renal infarcts experiencing a decline in renal function.

Comparison of Type II Endoleak Embolizations: Embolization of Endoleak Nidus Only versus Embolization of Endoleak Nidus and Branch Vessels.

PURPOSE: To compare outcomes of type II endoleak embolization involving embolization of the endoleak nidus only vs embolization of the endoleak nidus and branch vessels in patients treated with endovascular repair of abdominal aortic aneurysms. MATERIALS AND METHODS: Twenty-nine consecutive patients (mean age, 77.9 y; range, 63-88 y) with type II endoleak who underwent embolization from 2004 to 2015 were retrospectively reviewed. Patients were divided into 2 groups: embolization of endoleak nidus only (group A) and embolization of endoleak nidus and branch vessels (group B). Mean follow-up intervals were 20.5 months ± 14.7 in group A and 24.3 months ± 18.5 in group B. Outcomes were compared between groups by Mann-Whitney U and Pearson χ2 tests. RESULTS: Mean interval from endovascular aneurysm repair to embolization was 47.6 months ± 42.9, and mean presentation time of endoleak before embolization was 23.1 months ± 25.8. Coils (n = 28) and liquid embolic agents (n = 23) were used for embolization. There were no significant differences in rates of residual endoleak (50% vs 53.8%; P = .96) or sac decrease/stabilization (62.5% vs 61.5%; P = .64). Procedure time and radiation exposure in group B (132.3 min ± 78.1; 232.4 Gy·cm2 ± 130.7) were greater than in group A (63.4 min ± 11.9; 61.5 Gy·cm2 ± 35.5; P < .01). There were no procedure-related complications. CONCLUSIONS: Embolization of the endoleak nidus and branch vessels is not superior to embolization of only the nidus in terms of occlusion of type II endoleak and change in sac size despite requiring longer procedure times and resulting in greater patient radiation exposure.

Review of Current Literature for Prostatic Artery Embolization.

Prostatic artery embolization (PAE) is an emerging, novel interventional technique in the management of patients with lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH). BPH is a common clinical condition in middle-aged and elderly men resulting in LUTS, including nocturia, urinary frequency, urgency, decreased urinary flow rates, hesitancy, and incomplete bladder emptying. Traditionally, LUTSs have been managed by medical or surgical therapies. Since the initial incidental discovery that selective PAE performed for uncontrolled bleeding secondary to BPH resulted in improved LUTS, the technique has continually evolved with a growing body of evidence supporting its safety and efficacy. However, despite the available data, PAE has yet to be established as a standard-of-care treatment option for patients with LUTS/BPH. In this article, the authors review the history and current state of PAE, including published data from case reports, animal studies, retrospective/prospective cohort studies, and prospective randomized controlled trials.

Prostatic Artery Embolization Using Embosphere Microspheres for Prostates Measuring 80-150 cm(3): Early Results from a US Trial.

Between November 2014 and October 2015, 12 patients with prostates measuring 80-150 cm(3) and lower urinary tract symptoms (LUTSs) were enrolled in a prospective single-center US trial to evaluate Embosphere Microspheres for use in prostatic artery embolization (PAE). At 3 months, mean improvements in International Prostate Symptom Score and quality of life score were 18.3 points (range, 5-27) and 3.6 points (range, 1-6), respectively. One-month cystoscopies and anoscopies demonstrated no ischemic injuries. There were no major complications. In this cohort, Embosphere Microspheres, when used for PAE, were safe and effective in reducing LUTSs in the early follow-up period.

Technical Feasibility of Prostatic Artery Embolization From a Transradial Approach.

OBJECTIVE: The objective of this study was to evaluate the technical feasibility of performing prostatic artery embolization (PAE) with a transradial approach (TRA). Nineteen consecutive PAEs performed using a TRA were reviewed to determine the technical success of the procedure, which was defined as bilateral embolization. Procedural details, complications, and limitations were recorded. CONCLUSION: Technical success was achieved in all 19 procedures. The associated complications were minor and included two small (< 5 cm) hematomas and one potential case of delayed radial arteritis. PAE performed with a TRA is technically feasible.

Assessing medical students' knowledge of IR at two American medical schools.

PURPOSE: To determine if there was a difference in the level of knowledge about interventional radiology (IR) between medical students in preclinical years of training compared with medical students in clinical years of training at two medical schools and to compare awareness of IR based on the curriculum at each school: one with required radiology education and one without such a requirement. MATERIALS AND METHODS: An anonymous survey was distributed to students at two medical schools; the survey assessed knowledge of IR, knowledge of training pathways, and preferred methods to increase exposure. Responses of the preclinical and clinical groups were compared, and responses from the clinical groups at each school were compared. RESULTS: "Poor" or "fair" knowledge of IR was reported by 84% (n = 217 of 259) of preclinical students compared with 62% of clinical students (n = 110 of 177; P < .001). IR was being considered as a career by 11% of all students (15%, n = 40 of 259 preclinical; 5%, n = 9 of 177 clinical). The main reason respondents were not considering IR was "lack of knowledge" (65%, n = 136 of 210 preclinical; 20%, n = 32 of 162 clinical). Students in the clinical group at the institution with a required radiology rotation reported significantly better knowledge of IR than clinical students from the institution without a required clerkship (P = .017). CONCLUSIONS: There are significant differences in knowledge of IR between preclinical and clinical students. Required radiology education in the clinical years does increase awareness of IR.

Comparison of percutaneous ablation technologies in the treatment of malignant liver tumors.

Tumor ablation is a minimally invasive technique used to deliver chemical, thermal, electrical, or ultrasonic damage to a specific focal tumor in an attempt to achieve substantial tumor destruction or complete eradication. As the technology continues to advance, several image-guided tumor ablations have emerged to effectively manage primary and secondary malignancies in the liver. Percutaneous chemical ablation is one of the oldest and most established techniques for treating small hepatocellular carcinomas. However, this technique has been largely replaced by newer modalities including radiofrequency ablation, microwave ablation, laser-induced interstitial thermotherapy, cryoablation, high-intensity-focused ultrasound ablation, and irreversible electroporation. Because there exist significant differences in underlying technological bases, understanding each mechanism of action is essential for achieving desirable outcomes. In this article, the authors review the current state of each ablation method including technological and clinical considerations.

ACR Appropriateness Criteria radiologic management of benign and malignant biliary obstruction.

The optimal treatment for patients with biliary obstruction varies depending on the underlying cause of the obstruction, the clinical condition of the patient, and anticipated long-term effects of the procedure performed. Endoscopic and image-guided procedures are usually the initial procedures performed for biliary obstructions. Various options are available for both the radiologist and endoscopist, and each should be considered for any individual patient with biliary obstruction. This article provides an overview of the current status of radiologic procedures performed in the setting of biliary obstruction and describes multiple clinical scenarios that may be treated by radiologic or other methods. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

ACR Appropriateness Criteria radiologic management of hepatic malignancy.

Management of hepatic malignancy is a challenging clinical problem involving several different medical and surgical disciplines. Because of the wide variety of potential therapies, treatment protocols for various malignancies continue to evolve. Consequently, development of appropriate therapeutic algorithms necessitates consideration of medical options, such as systemic chemotherapy; surgical options, such as resection or transplantation; and locoregional therapies, such as thermal ablation and transarterial embolization. The authors discuss treatment strategies for the 3 most common subtypes of hepatic malignancy treated with locoregional therapies: hepatocellular carcinoma, neuroendocrine metastases, and colorectal metastases. The ACR Appropriateness Criteria(®) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

ACR appropriateness criteria® radiologic management of thoracic nodules and masses.

Pulmonary and mediastinal masses represent a wide range of pathologic processes with very different treatment options. Although advances in imaging (such as PET and high-resolution CT) help in many cases with the differential diagnosis of thoracic pathology, tissue samples are frequently needed to determine the best management for patients presenting with thoracic masses. There are many options for obtaining tissue samples, each of which has its own set of benefits and drawbacks. The purposes of this report are to present the most current evidence regarding biopsies of thoracic nodules and masses and to present the most appropriate options for select common clinical scenarios. The ACR Appropriateness Criteria(®) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.