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Rationale and Objectives: To evaluate the image quality and suitability of Dual-Source Dual-Energy CT venography (DSDE-CTV) with asynchronous virtual monoenergetic images (VMI+) of the entire lower extremity in the context of pre-surgical assessment of complex cases prior to coronary bypass graft as a feasibility study.Materials and Methods: Fifteen consecutive patients, consisting of 5 females and 10 males with an average age of 52 ± 17 years underwent DSDE-CTV from the pubic symphysis to the ankles after intravenous injection of an iodinated contrast medium. DSDE-CTV was acquired with tube voltages of 80 kVp and sn140 kVp. Single spectrum images (A - 80 kVp; B - 140 kVp) as well as a linearly blended mixed data set (M_0.6) were reconstructed. By postprocessing, an VMI+ dataset at 40 keV was generated. Objective image quality parameters of the deep and superficial veins of thigh, knee, and calves were measured separately for each location. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Additionally, subjective image quality was assessed independently by two radiologists.Results: Mean vascular attenuation was 73.9 ± 17.8 HU at B, 113.7 ± 42.2 HU at M_0.6, 119.4 ± 45.5 HU at A, and 201.0 ± 89.7 HU at VMI+. Mean CNR was 6.7 ± 2.0 at 140 keV, 9.25 ± 2.3 in the M_0.6 datasets, 8.7 ± 3.0 at 80 keV, and 12.9 ± 4.3 at 40 keV. Attenuation values were approximately doubled when compared to the reference standard (M_0.6) with significantly improved SNR and CNR (p < 0.05). Subjective image quality scores were highest for VMI+ datasets (4.1 ± 0.5) and lowest for B datasets (2.3 ± 0.37), however differences between VMI+ datasets and M_0.6 datasets did not reach statistical significance.Conclusion: Postprocessing of dual-energy CTV with VMI+ significantly increases attenuation of veins and markedly improves SNR and CNR values, thereby improving the diagnostic quality of CTV for the evaluation of deep and superficial veins of the entire lower limb prior to coronary bypass graft. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: To identify the influence and artifact burden in cardiac CT imaging of a leadless cardiac pacemaker (LCP) performed with all three generations of DualSource CT (DSCT) Scanners.Materials and Methods: The LCP was examined in DSCT scanners of the first to third generation using DualEnergy (DECT) and DSCT as well as alterations of the current-time product. For DECT examinations, virtual monoenergetic images were computed manually on a dedicated workstation. Virtual voltage was manually selected by subjective assessment of the lowest artifact burden. Systematic variations of the pacemaker angle to the gantry were assessed, too. The angle was successively increased by 10°, ranging from 0° to 90°. Artifact burden was quantified on a five-point Likert scale (1- no artifacts, 2- few artifacts, 3- moderate artifacts, 4- many artifacts, and 5- massive artifacts). Likert values of 1-3 were considered diagnostic and assessed by two board-certified radiologists in consensus.Results: In total, 200 examinations were analyzed, a mean Likert value of 1.93 ± 0.61 was found overall. None of the images were assessed Likert value >3. The positioning evaluation showed a clear and significant reduction of artifact burden toward lower angles, (0°: 1.4 ± 0.5 vs. 90° 2.55 ± 0.51). At scanner level, second-generation DSCT performed significantly better (1.68 ± 0.47) than both other scanners. Comparison of technique (DECT vs. DSCT) revealed a significantly improved image quality in DSCT examinations.Conclusion: LCP can be safely examined in DSCT scanner of the first to third generation with the evaluated protocols and techniques, which are currently in use. Artifact burden can be significantly reduced by aligning or approaching the LCP's longitudinal axis toward the scanner's z-axis. [ABSTRACT FROM AUTHOR]

• Coastal Aerosol Band 1 (b1) is important for coastal aquatic applications. • Satelite Bathymetry is improved when b1 is included. • Coastal habitats have been mapped down to 32.2 m. Coastal habitats provide a plethora of ecosystem services, yet they undergo continuous pressure and degradation due to the human-induced climate change. Conservation and management imply continuous monitoring and mapping of their spatial distribution at first. The present study explores the capabilities of the Copernicus Sentinel-2 mission and the contribution of its coastal aerosol band 1 (443 nm) for the mapping of the dominant Mediterranean coastal marine habitats and the bathymetry in three survey sites in the East Mediterranean. The selected sites have shallow to deep habitats and a high variability of oceanographic and seabed morphological conditions. The major findings of our study demonstrate the advantages of the downscaled Sentinel-2 coastal aerosol band 1 for both optically shallow habitat and satellite-derived bathymetry mapping due to its great water penetration. The use of Sentinel-2 band 1 allows detection of Posidonia oceanica seagrass beds down to 32.2 m of depth. Sentinel-2 constellation with its 10-m spatial resolution at most of the spectral bands, 5-day revisit frequency and open data policy can be an important tool to provide crucial missing information on the spatial distribution of coastal habitats and on their bathymetry distribution, especially in data-poor and/or remote areas with large gaps in a retrospective, rapid and non-intrusive manner. As such, it becomes a crucial ally for the conservation and management of coastal habitats globally. [ABSTRACT FROM AUTHOR]

Abstract Mediterranean seagrasses have been hailed for their numerous ecosystem services, yet they are undergoing a decline in their coverage. The major complication with resolving this tendency is the sparsity of data on their overall distribution. This study addresses the suitability of the recently launched Sentinel-2 satellite for mapping the distribution of Mediterranean seagrass meadows. A comprehensive methodology is presented which applies atmospheric and analytical water column corrections and compares the performance of three different supervised classifiers. Remote sensing of the Thermaikos Gulf, northwestern Aegean Sea (Greece, eastern Mediterranean Sea) reveals that the utilization of Support Vector Machines on water column corrected reflectances yields best accuracies. Two Mediterranean seagrasses, Posidonia oceanica and Cymodocea nodosa , cover a total submerged area of 1.48 km2 between depths of 1.4–16.5 m. With its 10-m spatial resolution and 5-day revisit frequency, Sentinel-2 imagery can mitigate the Mediterranean seagrass distribution data gap and allow better management and conservation in the future in a retrospective, time- and cost-effective fashion. Highlights • We demonstrate Sentinel-2 suitability for mapping two Mediterranean seagrasses. • Posidonia oceanica and Cymodocea nodosa are mapped between 1.4–16.5 m of depth. • Support Vector Machines perform better than Random Forests and Maximum Likelihood. • Atmospheric and water column corrections aid discrimination of the two seagrasses. • A satellite-derived bathymetry map of Thermaikos Gulf, NW Aegean Sea is developed. [ABSTRACT FROM AUTHOR]

Rationale and Objective: To identify the influence of various parameters for reducing artifacts in computed tomography (CT) of commonly used pacemakers or implantable cardioverter-defibrillator (ICD) lead tips.Materials and Methods: This ex vivo phantom study compared two CT techniques (Dual-Energy CT [DECT] vs. Dual-Source CT [DSCT]), as well as the influence of incremental alterations of current-time product and pacemaker lead-tip angle with respect to the gantry plane. Four pacemaker leads and one ICD lead were evaluated. The images were assessed visually on a five-point Likert scale (1 = artifact free to 5 = massive artifacts). Likert values 1-3 represent clinically relevant, diagnostic image quality.Results: 344 of 400 total images were rated with diagnostic image quality. The DECT and dual-source DSCT technique each scored 86% diagnostic image quality. Statistically, DECT images showed significantly improved image quality (P < .05). Concerning the current-time product, no statistically significant change was found. Regarding lead-tip positioning, an angle of ≤70° yielded 100% diagnostic image quality. Pacemaker and ICD leads were assessed to have statistically significant differences.Conclusions: Surprisingly, the lead-tip angle of 70° has been established as the key angle under which diagnostic image quality is always ensured, regardless of the imaging technique. Thus, we call 70° the "Magic angle" in CT pacemaker imaging. [ABSTRACT FROM AUTHOR]

At present, the copper chelator d -penicillamine (DPA) is the first-line therapy of Wilson’s disease (WD), which is characterized by an excessive copper overload. Lifelong DPA treatments aim to reduce the amount of detrimental excess copper retention in the liver and other organs. Although DPA shows beneficial effect in many patients, it may cause severe adverse effects. Despite several years of copper chelation therapy, discontinuation of DPA therapy can be linked to a rapidly progressing liver failure, indicating a high residual liver copper load. In order to investigate the spatial distribution of remaining copper and additional elements, such as zinc and iron, in rat and human liver samples after DPA treatment, a high resolution (spotsize of 10 μm) laser ablation-inductively coupled plasma-mass spectrometry (LA‐ICP‐MS) imaging method was applied. Untreated LPP ‐/− rats, an established animal model for WD, appeared with a high overall copper concentration and a copper distribution of hotspots distributed over the liver tissue. In contrast, a low (>2-fold decreased) overall copper concentration was detected in liver of DPA treated animals. Importantly, however, copper distribution was highly inhomogeneous with lowest concentrations in direct proximity to blood vessels, as observed using novel zonal analysis. A human liver needle biopsy of a DPA treated WD patient substantiated the finding of an inhomogeneous copper deposition upon chelation therapy. In contrast, comparatively homogenous distributions of zinc and iron were observed. Our study indicates that a high resolution LA‐ICP‐MS analysis of liver samples is excellently suited to follow efficacy of chelator therapy in WD patients. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: Particularly for patients with heart arrhythmias, conventional BestSystole (BS) and BestDiastole (BD) reconstruction techniques in computed tomography (CT) frequently show artifacts that hinder the readability of the coronary tree. To address this problem, this paper presents an alternative reconstruction method that combines the technique "reconstructions with identical filling" (RIF) with motion mapping: This new technique is called "RIF in motion mapping" (RIMM). This study compares the diagnostic quality of images generated with RIMM to that of the other reconstruction techniques.Materials and Methods: Having shown major artifacts in standard reconstructions, the CT datasets of 23 patients with suspected coronary artery disease or prior to transcatheter aortic valve replacement were selected manually. Each dataset was evaluated with four reconstruction techniques: BS, BD, RIF, and RIMM. Two radiologists, blinded to the applied reconstruction type, then evaluated the entire coronary tree of each sample using the 15-segment American Heart Association model and the six-grade Likert scale.Results: Of the 345 analyzed coronary segments, the RIMM technique showed a significant number of images with reliable diagnostic quality (n = 228, 66%) as compared to RIF (P = 0.002) and BS/BD reconstructions (P < 0.001). Per coronary segment, vessel, and patient, the RIMM technique scored significantly better than the conventional BS/BD reconstructions (P = 0.003) and better than the RIF reconstructions with regard to the right coronary artery (P = 0.041).Conclusions: This new technique works: Using RIMM on the worst CT images substantially erased many of these artifacts, thereby enabling the radiologists to clearly visualize these segments. As RIMM considerably eliminates artifacts, this new CT reconstruction technique can help make a fast reliable evaluation of a patient's coronary tree. Thus, this enhanced visualization of cardiac images by RIMM avoids the need for further invasive diagnostic procedures. [ABSTRACT FROM AUTHOR]

Purpose The aim of this study was to evaluate the usefulness of intra-operative visualisation, endoscopic assistance, and CT measurements for estimating the orbital fracture size and complexity. Methods Ten human cadaver heads were subjected to thin-slice computed tomography (CT). Standardised fractures were created using piezoelectric surgery in accordance with the Jaquiéry classification system. Four surgeons and one anatomist used six different observation methods to visualise and describe the orbital defects. Results The intraclass correlation coefficients (ICCs) for the fracture length measurements were relatively low for all observation methods (range, 0.666–0.883). CT measurements of width showed high consistency (ICC, 0.910). The surface area of the defect was highly overestimated by all methods (range, 121–184%). None of the observers was able to accurately estimate the length or width of 95% of the defects within an error range of ±0.75 cm. Conclusion CT measurements are the most consistent and accurate tool for estimating the critical size of orbital factures. In daily practice, a measurement tool in a DICOM viewer could be used, although software packages that allow manual adjustments are advisable. Direct intraoperative visualisation and surgeon experience are of limited value in the estimation of fracture size and complexity, and endoscopy provides no additional advantages. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: To investigate the correlation between prevalence and degree of coronary artery calcification (CAC) and extracoronary calcifications (ECCs), scored quantitatively according to Agatston and semiquantitatively by visual analysis, in chest computed tomography (CT) studies obtained for lung cancer screening in asymptomatic subjects and in patients with known coronary heart disease (CHD), and to compare the association of ECC and CAC to established cardiovascular risk factors.Materials and Methods: Prospective study on 501 males (67 ± 8 years) with a history of working dust exposure who underwent nongated low-dose chest CT for lung cancer screening. Of these, 63 (12.6%) had a history of CHD, the remaining 438 subjects (87.4%) were clinically asymptomatic and without a history of CHD. On the day of the CT study, subjects underwent a thorough clinical examination including blood tests and completed a standardized questionnaire to establish a complete medical history. ECC and CAC scores were quantified according to Agatston and, in addition, by visual rating of calcium load of individual vessel territories on a five-point scale from "absent" to "extensive." Results were correlated with the respective subjects' cardiovascular risk factors and with the presence or absence of CHD.Results: ECC scores correlated significantly with CAC scores (two-sided Spearman 0.515; P < .001). ECC scores were associated significantly (P < .001) with cardiovascular risk factors (smoking history, hypertension, diabetes, and hypercholesterolemia) and with subjects' Framingham/prospective cardiovascular münster study scores, whereas CAC scores were associated only with the presence of hypercholesterolemia. CAC scores were strongly associated with CHD than ECC scores (area under the curve, 0.88 vs. 0.66 at receiver operating characteristic analysis). Visual scoring of ECC/CAC load correlated closely with the respective Agatston values (P < .001) and revealed the same association (or lack thereof) with cardiovascular risk factors/CHD.Conclusions: In nongated low-dose CT for lung cancer screening, CAC and ECC load can be accurately established by visual analysis. ECC and CAC scores correlate closely, but not perfectly. There is a strong association between established cardiovascular risk factors and ECC load, but not CAC load, providing further evidence that ECC scoring may complement CAC scoring for broader risk assessment, for example, regarding prediction of extracoronary vascular events. [ABSTRACT FROM AUTHOR]

Regarding to the limitations and benefits of remote sensing sensors, fusion of remote sensing data from multiple sensors such as hyperspectral and LIDAR (light detection and ranging) is effective at land cover classification. Hyperspectral images (HSI) provide a detailed description of the spectral signatures of classes, whereas LIDAR data give height detailed information. However, because of the more complexities and mixed information in LIDAR and HSI, traditional crisp classification methods could not be more efficient. In this situation, fuzzy classifiers could deliver more satisfactory results than crisp classification approaches. Also, referring to the limitation of single classifiers, multiple classifier system (MCS) may exhibit better performance in the field of multi-sensor fusion. This paper presents a fuzzy multiple classifier system for fusions of HSI and LIDAR data based on decision template (DT). After feature extraction and feature selection on each data, all selected features of both data are applied on a cube. Then classifications were performed by fuzzy k -nearest neighbour (FKNN) and fuzzy maximum likelihood (FML) on cube of features. Finally, a fuzzy decision fusion method is utilized to fuse the results of fuzzy classifiers. In order to assess fuzzy MCS proposed method, a crisp MCS based on support vector machine (SVM), KNN and maximum likelihood (ML) as crisp classifiers and naive Bayes (NB) as crisp classifier fusion method is applied on selected cube feature. A co-registered HSI and LIDAR data set from Houston of USA was available to examine the effect of proposed MCSs. Fuzzy MCS on HSI and LIDAR data provide interesting conclusions on the effectiveness and potentialities of the joint use of these two data. [ABSTRACT FROM AUTHOR]

Background A proportion of patients with adult-onset asthma have severe disease. Risk factors for an increase in asthma severity are poorly known. Objective We sought to identify predictors for the development of severe asthma in adults. Methods A cohort of 200 adults with new-onset asthma was prospectively followed for 2 years. At baseline, patients underwent a comprehensive assessment of clinical, functional, and inflammatory parameters. After 2 years, change in asthma severity was assessed by using the Global Initiative for Asthma score (range, 1-4), which is based on asthma control (Asthma Control Questionnaire), lung function (FEV 1 ), and inhaled corticosteroid requirement. ANOVA and multiple regression equations were used in the analysis. Results One hundred twenty-eight patients completed 2 years of follow-up. Seventeen (13.3%) patients had an increase in asthma severity, whereas 53 (41.4%) patients had a decrease. A lower postbronchodilator FEV 1 /forced vital capacity ratio and a higher number of cigarette pack years smoked at baseline were significantly associated with an increase in asthma severity at follow-up. Multiple regression equations showed that only the number of cigarette pack years smoked was independently associated with an increase in asthma severity, with an odds ratio of 1.4 (95% CI, 1.02-1.91) for every 10 pack years smoked. Conclusion A history of cigarette smoking in patients with new-onset adult asthma predicts an increase in asthma severity during the first 2 years of the disease in a dose-dependent manner. [ABSTRACT FROM AUTHOR]

Background: Sublingual immunotherapy (SLIT) is safe and effective as treatment of allergic rhinitis and mild asthma. Oral mucosal Langerhans cells (oLCs) play a central role. However, little is known about allergen binding by oLCs during mucosal allergen resorption and its impact on oLC functions. Objective: Binding of Phl p 5 to oLCs was studied in a standardized ex vivo model to investigate mechanisms important for SLIT. Methods: Human oral mucosal biopsies were incubated with the grass pollen allergen Phl p 5. Migration, binding of Phl p 5, phenotype and cytokine production, and T-cell priming of Phl p 5–binding oLCs were analyzed. Results: Significant uptake required more than 5 minutes, and dose-dependent binding of Phl p 5 to oLCs was saturated at 100 μg/mL Phl p 5. Furthermore, Phl p 5 significantly increased the migratory capacity of oLCs but attenuated their maturation and strongly promoted the release of TGF-β1 and IL-10 by oLCs themselves as well as by cocultured T cells. Conclusion: Oral mucosal Langerhans cells bind Phlp5 in a dose-dependent and time-dependent manner, leading to an increased production of tolerogenic cytokines and an enhanced migratory capacity but decelerated maturation of oLCs. [Copyright &y& Elsevier]