Ultrasound-Guided Chemical Component Separation with Botulinum Toxin A prior to Surgical Hernia Repair.

US-guided chemical component separation (CCS) of the abdominal musculature using botulinum toxin A can facilitate the surgical repair of large or complex hernias. Eight patients (2 women and 6 men with median age of 54 years [range, 34-78 years]) underwent preoperative US-guided CCS with hydrodissection before planned surgical repair of large or complex ventral (n = 4), inguinal (n = 2), and flank (n = 2) hernias by 2 interventional radiologists. Technical success rate of US-guided CCS procedures was 100%, and all patients achieved surgical closure a mean 34.1 days (range, 14-48 days) after US-guided CCS.

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.

The Beauty and Bane of Pressure-Directed Embolotherapy: Hemodynamic Principles and Preliminary Clinical Evidence.

OBJECTIVE: Particulate emboli are passive agents that follow blood flow. Deployed antireflux devices obstruct blood flow. CONCLUSION: The aim of this review is to describe the complex hemodynamic alterations to blood flow caused by the deployment of antireflux devices and the resulting changes to embolic distribution. The therapeutic goal is optimization of embolization safety and efficacy.

Prostatic Artery Embolization for Benign Prostatic Hyperplasia: Patient Evaluation, Anatomy, and Technique for Successful Treatment.

Symptomatic benign prostatic hyperplasia is a common condition in the aging population that results in bothersome lower urinary tract symptoms and decreased quality of life. Patients often are treated with medication and offered surgery for persistent symptoms. Transurethral resection of the prostate is considered the traditional standard of care, but several minimally invasive surgical treatments also are offered. Prostatic artery embolization (PAE) is emerging as an effective treatment option with few reported adverse effects, minimal blood loss, and infrequent overnight hospitalization. The procedure is offered to patients with moderate to severe lower urinary tract symptoms and depressed urinary flow due to bladder outlet obstruction. Proper patient selection and meticulous embolization are critical to optimize results. To perform PAE safely and avoid nontarget embolization, interventional radiologists must have a detailed understanding of the pelvic arterial anatomy. Although the prostatic arteries often arise from the internal pudendal arteries, several anatomic variants and pelvic anastomoses are encountered. Prospective cohort studies, small randomized controlled trials, and meta-analyses have shown improved symptoms after treatment, with serious adverse effects occurring rarely. This article reviews the basic principles of PAE that must be understood to develop a thriving PAE practice. These principles include patient evaluation, review of surgical therapies, details of pelvic arterial anatomy, basic principles of embolization, and an overview of published results. Online supplemental material is available for this article. ©RSNA, 2019.

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.

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.

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.

Radiation dose associated with CT-guided drain placement for pediatric patients.

BACKGROUND: To date, there are limited radiation dose data on CT-guided procedures in pediatric patients. OBJECTIVE: Our goal was to quantify the radiation dose associated with pediatric CT-guided drain placement and follow-up drain evaluations in order to estimate effective dose. MATERIALS AND METHODS: We searched the electronic medical record and picture archiving and communication system (PACS) to identify all pediatric (<18 years old) CT-guided drain placements performed between January 2008 and December 2013 at our institution. We compiled patient data and radiation dose information from CT-guided drain placements as well as pre-procedural diagnostic CTs and post-procedural follow-up fluoroscopic abscess catheter injections (sinograms). Then we converted dose-length product, fluoroscopy time and number of acquisitions to effective doses using Monte Carlo simulations and age-appropriate conversion factors based on annual quality-control testing. RESULTS: Fifty-two drainages were identified with mean patient age of 11.0 years (5 weeks to 17 years). Most children had diagnoses of appendicitis (n=23) or inflammatory bowel disease (n=11). Forty-seven patients had diagnostic CTs, with a mean effective dose of 7.3 mSv (range 1.1-25.5 mSv). Drains remained in place for an average of 16.9 days (range 0-75 days), with an average of 0.9 (0-5) sinograms per patient in follow-up. The mean effective dose for all drainages and follow-up exams was 5.3 mSv (0.7-17.1) and 62% (32/52) of the children had effective doses less than 5 mSv. CONCLUSION: The majority of pediatric patients who have undergone CT-guided drain placements at our institution have received total radiation doses on par with diagnostic ranges. This information could be useful when describing the dose of radiation to parents and providers when CT-guided drain placement is necessary.

Tumor Microenvironment-Mediated Construction and Deconstruction of Extracellular Drug-Delivery Depots.

Protein therapy has been considered the most direct and safe approach to treat cancer. Targeting delivery of extracellularly active protein without internalization barriers, such as membrane permeation and endosome escape, is efficient and holds vast promise for anticancer treatment. Herein, we describe a "transformable" core-shell based nanocarrier (designated CS-NG), which can enzymatically assemble into microsized extracellular depots at the tumor site with assistance of hyaluronidase (HAase), an overexpressed enzyme at the tumor microenvironment. Equipped with an acid-degradable modality, the resulting CS-NG can substantially release combinational anticancer drugs-tumor necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL) and antiangiogenic cilengitide toward the membrane of cancer cells and endothelial cells at the acidic tumor microenvironment, respectively. Enhanced cytotoxicity on MDA-MB-231 cells and improved antitumor efficacy were observed using CS-NG, which was attributed to the inhibition of cellular internalization and prolonged retention time in vivo.

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.

Ultralow Iodine Dose Transarterial Catheter-Directed CT Angiography for Fenestrated Endovascular Aortic Repair Planning.

BACKGROUND: Preoperative planning for fenestrated endovascular aortic repair (fEVAR) requires high-quality cross-sectional imaging, most commonly computed tomography angiography (CTA). However, in the setting of chronic kidney disease (CKD), the iodine load delivered during conventional CTA is associated with risk for acute kidney injury (AKI). In this report, we describe the feasibility of using transarterial catheter directed CT angiography (tcd-CTA) with ultralow-dose iodine as an alternative for fEVAR planning in patients with stage 3-4 CKD to lower the risk of AKI. METHODS: Preserum and postserum creatinine levels were retrospectively evaluated from 8 patients with stage 3-4 CKD who underwent tcd-CTA with 20 mL of Iohexol for fEVAR planning for the treatment of pararenal abdominal aortic aneurysms. The tcd-CTA images were evaluated by two vascular surgeons for adequacy for fEVAR planning and progression to fEVAR completion was recorded. RESULTS: The mean serum creatinine before tcd-CTA was 2.1 ± .32 mg/dL, and the mean estimated glomerular filtration rate was 29.7 ± 6.31 mL/min/1.73 m(2). After tcd-CTA, the mean serum creatinine was 1.9 ± .25 mg/dL and the mean estimated glomerular filtration rate was 32.9 ± 5.12 mL/min/1.73 m(2). All 8 of the studies were determined to be adequate for fEVAR planning independently by two vascular surgeons. Six of the patients underwent successful fEVAR and 2 opted for watchful waiting. CONCLUSIONS: tcd-CTA with ultralow-dose iodine is a feasible option for pre-fEVAR planning in patients with stage 3-4 CKD.

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.