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At least 811 records · Page 45

Pictorial review on abdominal applications of ferumoxytol in MR imaging

Though gadolinium-based contrast agents are the most widely used contrast media in MR for clinical use, problems with nephrogenic systemic fibrosis and tissue deposition render their safety debatable, at least in a selected patient population. Ferumoxytol has the potential to be used as an alternate contrast medium for various clinical applications across multiple organs. It has prolonged intravascular signal and delayed intracellular macrophage uptake which are unique properties compared to gadolinium-based agents. This pictorial review aims to review the current and potential clinical applications of ferumoxytol as a contrast agent in abdominal MR imaging.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

A Systematic Review of Protocols for the Three-Dimensional Morphologic Assessment of Abdominal Aortic Aneurysms Using Computed Tomographic Angiography

The morphology of infrarenal abdominal aortic aneurysms (AAAs) directly influences the perioperative outcome and long-term durability of endovascular aneurysm repair. A variety of methods have been proposed for the characterization of AAA morphology using reconstructed three-dimensional (3D) computed tomography (CT) images. At present, there is lack of consensus as to which of these methods is most applicable to clinical practice or research. The purpose of this review was to evaluate existing protocols that used 3D CT images in the assessment of various aspects of AAA morphology. An electronic search was performed, from January 1996 to the end of October 2010, using the Embase and Medline databases. The literature review conformed to PRISMA statement standards. The literature search identified 604 articles, of which 31 studies met inclusion criteria. Only 15 of 31 studies objectively assessed reproducibility. Existing published protocols were insufficient to define a single evidence-based methodology for preoperative assessment of AAA morphology. Further development and expert consensus are required to establish a standardized and validated protocol to determine precisely how morphology relates to outcomes after endovascular aneurysm repair.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Endovascular Treatment of Active Splenic Bleeding After Colonoscopy: A Systematic Review of the Literature

Purpose: Colonoscopy is reported to be a safe procedure that is routinely performed for the diagnosis and treatment of colorectal diseases. Splenic rupture is considered to be a rare complication with high mortality and morbidity that requires immediate diagnosis and management. Nonoperative management (NOM), surgical treatment (ST), and, more recently, proximal splenic artery embolization (PSAE) have been proposed as treatment options. The goal of this study was to assess whether PSAE is safe even in high-grade ruptures. Methods: We report two rare cases of post colonoscopy splenic rupture. A systematic review of the literature from 2002 to 2010 (first reported case of PSAE) was performed and the three types of treatment compared. Results: All patients reviewed (77 of 77) presented with intraperitoneal hemorrhage due to isolated splenic trauma. Splenic rupture was high-grade in most patients when grading was possible. Six of 77 patients (7.8 %) were treated with PSAE, including the 2 cases reported herein. Fifty-seven patients (74 %) underwent ST. NOM was attempted first in 25 patients with a high failure rate (11 of 25 [44 %]) and requiring a salvage procedure, such as PSAE or ST. Previous surgery (31 of 59 patients), adhesions (10 of 13), diagnostic colonoscopies (49 of 71), previous biopsies or polypectomies (31 of 57) and female sex (56 of 77) were identified as risk factors. In contrast, splenomegaly (0 of 77 patients), medications that increase the risk of bleeding (13 of 30) and difficult colonoscopies (16 of 51) were not identified as risk factors. PSAE was safe and effective even in elderly patients with comorbidities and those taking medications that increase the risk of bleeding, and the length of the hospital stay was similar to that after ST. Conclusion: We propose a treatment algorithm based on clinical and radiological criteria. Because of the high failure rate after NOM, PSAE should be the treatment of choice to manage grade I through IV splenic ruptures after colonoscopy in hemodynamically stabilized patients.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Systematic Review of Infrapopliteal Drug-Eluting Stents: A Meta-Analysis of Randomized Controlled Trials

IntroductionDrug-eluting stents (DES) have been proposed for the treatment of infrapopliteal arterial disease. We performed a systematic review to provide a qualitative analysis and quantitative data synthesis of randomized controlled trials (RCTs) assessing infrapopliteal DES.Materials and MethodsPubMed (Medline), EMBASE (Excerpta Medical Database), AMED (Allied and Complementary medicine Database), Scopus, CENTRAL (Cochrane Central Register of Controlled Trials), online content, and abstract meetings were searched in September 2012 for eligible RCTs according to the preferred reporting items for systematic reviews and meta-analyses selection process. Risk of bias was assessed using the Cochrane Collaboration's tool. Primary endpoint was primary patency defined as absence of {>=}50 % vessel restenosis at 1 year. Secondary outcome measures included patient survival, limb amputations, change of Rutherford-Becker class, target lesion revascularization (TLR) events, complete wound healing, and event-free survival at 1 year. Risk ratio (RRs) were calculated using the Mantel-Haenszel fixed effects model, and number-needed-to-treat values are reported.ResultsThree RCTs involving 501 patients with focal infrapopliteal lesions were analyzed (YUKON-BTX, DESTINY, and ACHILLES trials). All three RCTs included relatively short and focal infrapopliteal lesions. At 1 year, there was clear superiority of infrapopliteal DES compared with control treatments in terms of significantly higher primary patency (80.0 vs. 58.5 %; pooled RR = 1.37, 95 % confidence interval [CI] = 1.18-1.58, p < 0.0001; number-needed-to-treat (NNT) value = 4.8), improvement of Rutherford-Becker class (79.0 vs. 69.6 %; pooled RR = 1.13, 95 % CI = 1.002-1.275, p = 0.045; NNT = 11.1), decreased TLR events (9.9 vs. 22.0 %; pooled RR = 0.45, 95 % CI = 0.28-0.73, p = 0.001; NNT = 8.3), improved wound healing (76.8 vs. 59.7 %; pooled RR = 1.29, 95 % CI = 1.02-1.62, p = 0.04; NNT = 5.9), and better overall event-free survival (72.2 vs. 57.3 %; pooled RR = 1.26, 95 % CI = 1.10-1.44, p = 0.0006; NNT = 6.7). Conclusion. DES for focal infrapopliteal lesions significantly inhibit vascular restenosis and thereby improve primary patency, decrease repeat procedures, improve wound healing, and prolong overall event-free survival.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Retrospective review of thoracic neural damage during lung ablation - what the interventional radiologist needs to know about neural thoracic anatomy

Background and Purpose: Radiofrequency ablation (RFA) is associated with low neural morbidity compared with surgery, which commonly causes debilitating long-term pain. The purpose was to review the thoracic neural anatomy relevant to percutaneous RFA and to retrospectively review symptomatic nerve injury after lung RFA at our institution. Materials and Methods: We retrospectively examined all symptomatic nerve injuries occurring after computed tomography (CT)-guided RFA treatment of lung tumors for 462 patients/509 procedures/708 lesions treated at our large tertiary referral centre during 10 years. Results: Eight patients experienced neurological complications after heating during the RFA procedure. These complications occurred in the phrenic (n = 1), brachial (n = 3), left recurrent (n = 1), and intercostal nerves (n = 2) and the stellate ganglion (n = 1). Three were grade 2, four grade 3 and one grade 4 injuries (CTCAE v3). Conclusion: Although rare, neurological complications can occur after RFA, and they can occasionally be severe. To prevent these complications, it is important for the interventional radiologist to be aware of the anatomy of nervous structures and to attempt to identify nerves on CT scans during the RFA procedure. Creating a pneumothorax can be useful to avoid nerve damage and related clinical complications.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

The Management of Cephalic Arch Stenosis in Arteriovenous Fistulas for Hemodialysis: A Systematic Review

AimTo conduct a systematic review of management of current cephalic arch stenosis (CAS) and associated outcomes in the context of dysfunctional hemodialysis access.Materials and MethodsPubMed, Web of Science, and Cochrane Library were searched to retrieve literature on the management of CAS. Studies had to focus on management of access stenosis solely in the cephalic arch. Case reports and literature reviews were excluded. Studies were categorized by intervention, and primary and secondary patency data were compiled. Studies were aggregated, and meta-analyses were performed where possible.ResultsNine papers satisfied the aforementioned criteria: five were retrospective studies and four were prospective studies. CAS management strategies have included percutaneous transluminal balloon angioplasty (PTA), peripheral cutting balloons, surgical cephalic vein transpositions, bare stents, and stent grafts. Reporting strategies varied between studies. Meta-analyses showed that results were variable even within studies using the same modality, particularly for PTA.ConclusionNo singular, definitive management strategy exists for CAS. Current studies are limited by being primarily single-center retrospective trials featuring heterogenous patient populations, interventions, and endpoints. Priorities for future studies should include larger randomized trials, more uniform management strategies and endpoints, and a longer duration of follow-up.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Comparing Percutaneous Transluminal Angioplasty and Stent Placement for Treatment of Subclavian Arterial Occlusive Disease: A Systematic Review and Meta-Analysis

Background and PurposeSubclavian artery occlusive disease (SAOD) is often associated with cerebrovascular symptoms such as subclavian steal syndrome and stroke. We conducted a systematic review and meta-analysis to compare percutaneous transluminal angioplasty (PTA) and stent placement for the treatment of SAOD.Materials and MethodsWe searched Medline, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus through October 16, 2014. From each study, we abstracted baseline patient characteristics, study design variables, and outcome data including rates of technical success, primary patency (≤2 and >2 years follow-up), symptom resolution, and complications. Meta-analysis was performed using a random-effects model.ResultsA total of 35 non-comparative studies with 1726 patients were included. Technical success rate was significantly higher in the stent group than the PTA group (92.8 vs 86.8 %, p = 0.007). Long-term primary patency rates (76.9 vs 79.6 %, p = 0.729) and symptom resolution rates (82.2 vs 73.0 %, p = 0.327) were not statistically different. There was no statistically significant difference in the rates of stroke or death.ConclusionStent placement for treatment of SAOD may be associated with higher rates of technical success but similar rates of symptom resolution and long-term outcomes. The confidence in the available estimates is low. Further comparative studies are needed to guide patients and clinicians in shared decision making.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

A Systematic Review of Prostatic Artery Embolization in the Treatment of Symptomatic Benign Prostatic Hyperplasia

PurposeTo summarize current evidence on outcomes and complications of prostatic artery embolization as a treatment for patients with lower urinary tract symptoms secondary to benign prostatic hyperplasia.Methods and MaterialsA database search of MEDLINE, Embase, Web of Science, and Cochrane Library was performed for published literature up to August 2015 concerning PAE in the treatment of BPH. Inclusion and exclusion criteria were applied by two independent reviewers, and disagreements were resolved by consensus. Peer-reviewed studies concerning PAE with BPH with a sample size >10 and at least one measured parameter were included.ResultsThe search yielded 193 articles, of which ten studies representing 788 patients, with a mean age of 66.97 years, were included. Patients had LUTS ranging from moderate to severe. At 6 months following procedure, PV, PVR, Qmax, IPSS, and QoL were significantly improved (P < 0.05), while for PSA there was no significant change. At 12 and 24 months, PV, PSA, PVR, Qmax, IPSS, and QoL were significantly improved (P < 0.05). IIEF was unchanged at 6 and 12 months but was significantly reduced at 24 months.ConclusionThis suggests that PAE is effective in treating LUTS in the short and intermediate term.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Radiofrequency and Microwave Ablation Compared to Systemic Chemotherapy and to Partial Hepatectomy in the Treatment of Colorectal Liver Metastases: A Systematic Review and Meta-Analysis

PurposeTo assess safety and outcome of radiofrequency ablation (RFA) and microwave ablation (MWA) as compared to systemic chemotherapy and partial hepatectomy (PH) in the treatment of colorectal liver metastases (CRLM).MethodsMEDLINE, Embase and the Cochrane Library were searched. Randomized trials and comparative observational studies with multivariate analysis and/or matching were included. Guidelines from National Guideline Clearinghouse and Guidelines International Network were assessed using the AGREE II instrument.ResultsThe search revealed 3530 records; 328 were selected for full-text review; 48 were included: 8 systematic reviews, 2 randomized studies, 26 comparative observational studies, 2 guideline-articles and 10 case series; in addition 13 guidelines were evaluated. Literature to assess the effectiveness of ablation was limited. RFA + systemic chemotherapy was superior to chemotherapy alone. PH was superior to RFA alone but not to RFA + PH or to MWA. Compared to PH, RFA showed fewer complications, MWA did not. Outcomes were subject to residual confounding since ablation was only employed for unresectable disease.ConclusionThe results from the EORTC-CLOCC trial, the comparable survival for ablation + PH versus PH alone, the potential to induce long-term disease control and the low complication rate argue in favour of ablation over chemotherapy alone. Further randomized comparisons of ablation to current-day chemotherapy alone should therefore be considered unethical. Hence, the highest achievable level of evidence for unresectable CRLM seems reached. The apparent selection bias from previous studies and the superior safety profile mandate the setup of randomized controlled trials comparing ablation to surgery.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Post-Biopsy Manoeuvres to Reduce Pneumothorax Incidence in CT-Guided Transthoracic Lung Biopsies: A Systematic Review and Meta-analysis

This systematic review and meta-analysis investigated post-biopsy manoeuvres to reduce pneumothorax following computed tomography-guided percutaneous transthoracic lung biopsy. Twenty-one articles were included with 7080 patients. Chest drain insertion rates were significantly reduced by ninefold with the normal saline tract sealant compared to controls (OR 0.11, 95% CI 0.02–0.48), threefold with the rapid rollover manoeuvre to puncture site down (OR 0.34, 95% CI 0.18–0.63), threefold with the tract plug (OR 0.33, 95% CI 0.22–0.48) and threefold with the blood patch (OR 0.39, 95% CI 0.26–0.58). The absolute chest drain insertion rates were the lowest in the normal saline tract sealant (0.8% vs 7.3% for controls), rapid rollover (1.9% vs 5.2%), deep expiration and breath-hold on needle extraction (0.9% vs 1.8%) and standard rollover versus no rollover (2.6% vs 5.2%). These findings highlight post-biopsy manoeuvres which could help reduce pneumothorax and chest drain insertions following lung biopsies. Level of Evidence: Level 1/no level of evidence, systematic review.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Biological Recycling of Polyethylene Terephthalate: A Mini-Review

Plastics have become an inseparable part of our life in the society due to their merits such as low cost, light weight, good mechanical and thermal properties along with easy process ability. Since the last few decades, the unrestrained use of plastics in various fields like agriculture, packaging, transportation has raised a serious issue about its disposal and pollution. An efficient decomposition of plastics takes about 1000 years. Not only there is an increase in the problem of waste disposal of plastics but also they release CO{sub 2} and dioxins on burning which contributes to cause pollution. There is a growing concern for use of efficient microorganisms meant for biodegradation of non-degradable synthetic polymer because conventionally used methods for plastic disposal are ineffective for plastic waste management. This review paper focuses on one such type of plastic-polyethylene terephthalate (PET) which is widely used in a flexible packaging application, its manufacturing process and the various effects of waste generated by it on the surrounding environment. This review discusses an overview of various existing plastic disposal methods along with their limitations and mechanism of biodegradation of PET and factors affecting biodegradation.

54 ENVIRONMENTAL SCIENCES↗

Viscosity of Heterogeneous Silicate Melts: A Review

The viscosity of solid phase containing heterogeneous silicate melts is discussed in this review. The crucial parameters characterizing silicate melt structure are first presented, i.e., volume fraction of solid particles, particle shape and size. The measurement and calculation methods of these parameters are summarized and the influence of the parameters on viscosity is discussed. Next, a theoretical description of rheological behavior in heterogeneous silicate melts is given, focusing on non-Newtonian characteristics, e.g., shear-dependence, time-dependence, and yield stress. The viscosity models which were proposed in the last half century are reviewed and critically assessed. This paper concludes with opportunities and suggestions for future work.

36 MATERIALS SCIENCE↗

Review of cardiovascular imaging in the journal of nuclear cardiology in 2016: Part 2 of 2—myocardial perfusion imaging

In 2016, the Journal of Nuclear Cardiology published many high-quality articles. Similar to previous years, we will summarize here a selection of the articles that were published in the Journal in 2016 to provide a concise review of the main advancements that have recently occurred in the field. In the first article of this two-part series we focused on publications dealing with positron emission tomography, computed tomography, and magnetic resonance. This review will place emphasis on myocardial perfusion imaging using single-photon emission-computed tomography summarizing advances in the field including in diagnosis, prognosis, and appropriate use.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Guidelines in review: Comparison of ESC and AHA guidance for the diagnosis and management of infective endocarditis in adults

Over recent years, new evidence has led a rethinking of the available guidance on the diagnosis and management of infective endocarditis (IE). This review compares the most recently available guidance provided by the American Heart Association (AHA) IE Writing Committee, and the Task Force for the management of IE of the European Society of Cardiology (ESC). This represents the sixth of a new series of comparative guidelines review published in the Journal.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

A Review of Experimental Animal Radon Health Effects [Book Chapter]

Abundant epidemiological data from underground miners confirm that radon decay products (progeny) are carcinogenic, although the evidence is less conclusive on the quantitative risks of these exposures, especially for indoor air. The imprecision results principally from differences between exposures in mining and domestic environments and from uncertainties about the interaction between smoking and exposure to radon progeny. Experimental animal studies of radon-induced lung cancer are particularly valuable for understanding the carcinogenicity of human radon exposures in the home and in the workplace. Animals can be exposed to a variety of agents under carefully controlled conditions and then sacrificed for the study of developing lesions or held for their life span for tumor development. The doses to critical cells in the respiratory tract can be determined, and these in turn can be related to doses to critical cells in the respiratory tract of humans exposed to similar aerosols. The study of radon-induced mutations and changes in expression of oncogenes and tumor-suppressor genes as well as growth factors and growth factor receptors during tumor progression in animals also provides valuable evidence on the underlying mechanisms of radon carcinogenesis. This evidence, particularly that of the efficiency for oncogenic transformation at low dose rates, is crucial to the determination of the risk of lung cancer from exposure to indoor levels of radon. This review of animal health effects data emphasizes the carcinogenicity of radon exposures in rats; mechanistic data on radon-induced lung tumors in rats are currently sparse and are not reviewed here.

560162* -- Radionuclide Effects, Kinetics, & Toxic↗

Automated Extraction of Energy Systems Information from Remotely Sensed Data: A Review and Analysis

We report high quality energy systems information is a crucial input to energy systems research, modeling, and decision-making. Unfortunately, actionable information about energy systems is often of limited availability, incomplete, or only accessible for a substantial fee or through a non-disclosure agreement. Recently, remotely sensed data (e.g., satellite imagery, aerial photography) have emerged as a potentially rich source of energy systems information. However, the use of these data is frequently challenged by its sheer volume and complexity, precluding manual analysis. Recent breakthroughs in machine learning have enabled automated and rapid extraction of useful information from remotely sensed data, facilitating large-scale acquisition of critical energy system variables. Here we present a systematic review of the literature on this emerging topic, providing an in-depth survey and review of papers published within the past two decades. We first taxonomize the existing literature into ten major areas, spanning the energy value chain. Within each research area, we distill and critically discuss major features that are relevant to energy researchers, including, for example, key challenges regarding the accessibility and reliability of the methods. We then synthesize our findings to identify limitations and trends in the literature as a whole, and discuss opportunities for innovation. These include the opportunity to extend the methods beyond electricity to broader energy systems and wider geographic areas; and the ability to expand the use of these methods in research and decision making as satellite data become cheaper and easier to access. We also find that there are persistent challenges: limited standardization and rigor of performance assessments; limited sharing of code, which would improve replicability; and a limited consideration of the ethics and privacy of data.

97 MATHEMATICS AND COMPUTING↗

Corrosion resistance of steel fibre reinforced concrete - A literature review

Steel fibre reinforced concrete (SFRC) is increasingly being used in the construction of civil infrastructure. However, there are inconsistencies among international standards and guidelines regarding the consideration of carbon-steel fibres for the structural verification of SFRC exposed to corrosive environments. This paper presents a review of the published research regarding carbonation- and chloride-induced corrosion of SFRC, and proposes a deterioration theory for cracked SFRC exposed to chlorides and carbonation, based on the damage at the fibre-matrix interface. The review confirms an overall agreement among academics and regulators regarding the durability of uncracked SFRC exposed to chlorides and carbonation. Contrariwise, the durability of cracked SFRC is under discussion at the technical and scientific level, as there is a large dispersion on the experimental results and some of the mechanisms governing the corrosion of carbon-steel fibres in cracks and its effects on the fracture behaviour of SFRC are not fully understood.

36 MATERIALS SCIENCE↗

Effect of Permeability Heterogeneity on Area of Review

The Area of Review is one of the most important aspects of a geologic CO 2 storage site permit application and regulatory requirement. The US Environmental Protection Agency (EPA) has implemented an Area of Review (AoR) requirement for Class VI CO 2 injection wells for geologic sequestration. Reservoir permeability is one of the most important parameters controlling AoR evolution but is generally highly heterogeneous and difficult to constrain. We have used a numerical model for Rock Springs Uplift in Wyoming as an example site to characterize how the heterogeneity in reservoir permeability affects AoR. We have performed multiple reservoir simulations using multiple, equally-likely realizations of heterogeneous permeability. We considered multiple CO 2 injection scenarios with varying injection rates as well as varying injection and post-site durations. Results of our study demonstrate that uncertainty in permeability heterogeneity can significantly influence AoR for both CO 2 saturation and pressure. In our example, the CO 2 AoR varied by as much as 2-3 times while the pressure AoR varied over 1.5 – 2 times. Lastly, such type of variability can have significant implications in defining AoR for site permit applications.

58 GEOSCIENCES↗