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Δευτέρα, 12 Μαρτίου 2018

Radiation therapy in small cell lung cancer: a national Italian survey

Abstract

Introduction

Radiation therapy plays an important role in the management of SCLC both in curative and palliative setting, however, conflicting data from clinical trials incite debate over the appropriate use of radiation therapy regarding prophylactic cranial irradiation (PCI) and/or thoracic consolidative in extensive-stage SCLC (ES-SCLC). This survey is conducted to evaluate the current pattern of care among Italian radiation oncologists.

Methods

In June 2016, all Italian radiation oncologists were invited to a web-based survey. The survey contained 34 questions regarding the role of RT in SCLC. Questions pertaining the role of RT in the clinical management of both limited-stage (LS) and ES-SCLC were included.

Results

We received 48 responses from Italian radiation oncologists. More than half of respondents had been practicing for more than 10 years after completing residency training and 55% are subspecialists in lung cancer. Preferred management of LS-SCLC favored primary concurrent chemoradiotherapy (89%), even if the 36.9% usually delivered RT during or after the cycle 3 of chemotherapy, due to organizational issues. The most common dose and fractionation schedule in this setting was 60 Gy in 30 once-daily fractions. Furthermore, almost all respondents recommended PCI in patients with LS-SCLC. For ES-SCLC scenario, chemotherapy was defined the standard treatment by all respondents. PCI was recommended in ES-SCLC patients with thoracic complete remission (63% of respondents), with thoracic partial response (45%) and with thoracic stable disease (17%) after first-line chemotherapy. Lastly, the thoracic consolidative RT was recommended by 51% of respondents in patients with ES-SCLC in good response after first-line chemotherapy and a great variability was shown in clinical target volume definition, doses and fractionation schedules.

Conclusions

Our analysis showed a high adherence to current guidelines among the respondents in regard to chemoradiation approach in LS-SCLC patients and to PCI indications and doses. The great variability in radiation therapy doses and volumes in the thoracic consolidative radiotherapy in ES-SCLC is concerning. Future clinical trials are needed to standardize these treatment approaches to improve treatment outcomes among patients with ES-SCLC.



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Characterization of radon levels in soil and groundwater in the North Maladeta Fault area (Central Pyrenees) and their effects on indoor radon concentration in a thermal spa

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Publication date: September 2018
Source:Journal of Environmental Radioactivity, Volume 189
Author(s): V. Moreno, J. Bach, M. Zarroca, Ll. Font, C. Roqué, R. Linares
Radon levels in the soil and groundwater in the North Maladeta Fault area (located in the Aran Valley sector, Central Pyrenees) are analysed from both geological and radiation protection perspectives. This area is characterized by the presence of two important normal faults: the North Maladeta fault (NMF) and the Tredós Fault (TF). Two primary aspects make this study interesting: (i) the NMF shows geomorphic evidence of neotectonic activity and (ii) the presence of a thermal spa, Banhs de Tredós, which exploits one of the several natural springs of the area and needs to be evaluated for radiation dosing from radon according to the European regulation on basic safety standards for protection against ionizing radiation. The average soil radon and thoron concentrations along a profile perpendicular to the two normal faults — 22 ± 3 kBq·m−3 and 34 ± 3 kBq·m−3, respectively — are not high and can be compared to the radionuclide content of the granitic rocks of the area, 25 ± 4 Bq·kg−1 for 226Ra and 38 ± 2 Bq·kg−1 for 224Ra. However, the hypothesis that the normal faults are still active is supported by the presence of anomalies in both the soil radon and thoron levels that are unlikely to be of local origin together with the presence of similar anomalies in CO2 fluxes and the fact that the highest groundwater radon values are located close to the normal faults. Additionally, groundwater 222Rn data have complemented the hydrochemistry data, enabling researchers to better distinguish between water pathways in the granitic and non-granitic aquifers. Indoor radon levels in the spa vary within a wide range, [7–1664] Bq·m−3 because the groundwater used in the treatment rooms is the primary source of radon in the air. Tap water radon levels inside the spa present an average value of 50 ± 8 kBq·m−3, which does not exceed the level stipulated by the Spanish Nuclear Safety Council (CSN) of 100 kBq·m−3 for water used for human consumption. This finding implies that even relatively low radon concentration values in water can constitute a relevant indoor radon source when the transfer from water to indoor air is efficient. The estimated effective dose range of values for a spa worker due to radon inhalation is [1–9] mSv·y−1. The use of annual averaged radon concentration values may significantly underestimate the dose in these situations; therefore, a detailed dynamic study must be performed by considering the time that the workers spend in the spa.



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Correction to: Comparative cone-beam computed tomography evaluation of the osseous morphology of the temporomandibular joint in temporomandibular dysfunction patients and asymptomatic individuals

In the original publication of the article in "Abstract", the sentence that reads as "The present analyses suggest that a steeper articular eminence inclination may be risk factor" should read as "As a result of our analysis, we concluded that a low eminence angle may be risk factor".



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A model combining age, equivalent uniform dose and IL-8 may predict radiation esophagitis in patients with non-small cell lung cancer

Publication date: March 2018
Source:Radiotherapy and Oncology, Volume 126, Issue 3
Author(s): Shulian Wang, Jeff Campbell, Matthew H. Stenmark, Paul Stanton, Jing Zhao, Martha M. Matuszak, Randall K. Ten Haken, Feng-Ming Kong
Background and purposeTo study whether cytokine markers may improve predictive accuracy of radiation esophagitis (RE) in non-small cell lung cancer (NSCLC) patients.Materials and methodsA total of 129 patients with stage I–III NSCLC treated with radiotherapy (RT) from prospective studies were included. Thirty inflammatory cytokines were measured in platelet-poor plasma samples. Logistic regression was performed to evaluate the risk factors of RE. Stepwise Akaike information criterion (AIC) and likelihood ratio test were used to assess model predictions.ResultsForty-nine of 129 patients (38.0%) developed grade ≥2 RE. Univariate analysis showed that age, stage, concurrent chemotherapy, and eight dosimetric parameters were significantly associated with grade ≥2 RE (p < 0.05). IL-4, IL-5, IL-8, IL-13, IL-15, IL-1α, TGFα and eotaxin were also associated with grade ≥2 RE (p < 0.1). Age, esophagus generalized equivalent uniform dose (EUD), and baseline IL-8 were independently associated grade ≥2 RE. The combination of these three factors had significantly higher predictive power than any single factor alone. Addition of IL-8 to toxicity model significantly improves RE predictive accuracy (p = 0.019).ConclusionsCombining baseline level of IL-8, age and esophagus EUD may predict RE more accurately. Refinement of this model with larger sample sizes and validation from multicenter database are warranted.



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Photons, protons or carbon ions for stage I non-small cell lung cancer – Results of the multicentric ROCOCO in silico study

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Publication date: Available online 12 March 2018
Source:Radiotherapy and Oncology
Author(s): Krista C.J. Wink, Erik Roelofs, Charles B. Simone, David Dechambre, Alina Santiago, Judith van der Stoep, Wim Dries, Julia Smits, Stephen Avery, Filippo Ammazzalorso, Nicolas Jansen, Urszula Jelen, Timothy Solberg, Dirk de Ruysscher, Esther G.C. Troost
PurposeTo compare dose to organs at risk (OARs) and dose-escalation possibility for 24 stage I non-small cell lung cancer (NSCLC) patients in a ROCOCO (Radiation Oncology Collaborative Comparison) trial.MethodsFor each patient, 3 photon plans [Intensity-modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT) and CyberKnife], a double scattered proton (DSP) and an intensity-modulated carbon-ion (IMIT) therapy plan were created. Dose prescription was 60 Gy (equivalent) in 8 fractions.ResultsThe mean dose and dose to 2% of the clinical target volume (CTV) were lower for protons and ions compared with IMRT (p < 0.01). Doses to the lungs, heart, and mediastinal structures were lowest with IMIT (p < 0.01), doses to the spinal cord were lowest with DSP (p < 0.01). VMAT and CyberKnife allowed for reduced doses to most OARs compared with IMRT. Dose escalation was possible for 8 patients. Generally, the mediastinum was the primary dose-limiting organ.ConclusionOn average, the doses to the OARs were lowest using particles, with more homogenous CTV doses. Given the ability of VMAT and CyberKnife to limit doses to OARs compared with IMRT, the additional benefit of particles may only be clinically relevant in selected patients and thus should be carefully weighed for every individual patient.



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Editorial Board

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Publication date: March 2018
Source:Radiotherapy and Oncology, Volume 126, Issue 3





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Contents

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Publication date: March 2018
Source:Radiotherapy and Oncology, Volume 126, Issue 3





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Photons, protons or carbon ions for stage I non-small cell lung cancer – Results of the multicentric ROCOCO in silico study

To compare dose to organs at risk (OARs) and dose-escalation possibility for 24 stage I non-small cell lung cancer (NSCLC) patients in a ROCOCO (Radiation Oncology Collaborative Comparison) trial.

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Welcome to your new profile page

Over the years, the number of things you can do on Radiopaedia has increased. You can collect cases, contribute to articles, collate playlists, mark cases and articles as favourites, watch or attend our courses. You need to also have access to a bunch of account settings. These used to be scattered all over the place. Well no more. 

Now everything that pertains to your presence of Radiopaedia is in one place. Your new and improved profile page!

In addition to this, we have also taken this opportunity to launch achievements. These are a way of recognising the contribution a user, including you, has made to the site. These badges are shown on your public profile. You level-up as you contribute to the site in a variety of ways. 

And lastly, and this is especially important to all you who have hundreds of cases, playlists and favourites, you can now search and filter just your own collection. 

I hope you enjoy using these new features as much as we have enjoyed creating them for you. 

Frank 

 

 

Associate Professor Frank Gaillard is the Founder and Editor in Chief of Radiopaedia.org. He is also an academic neuroradiologist and Director of Research in the Radiology Department of the Royal Melbourne Hospital/University of Melbourne in Melbourne, Australia.



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Evaluation of Safety, Efficacy and Clinical Outcome after Endovascular Treatment of Aneurysmal Subarachnoid Haemorrhage In Coil-First Setting A 10-Year Series from a Single Centre

Publication date: Available online 12 March 2018
Source:Journal of Neuroradiology
Author(s): Muhammad AlMatter, Pervinder Bhogal, Marta Aguilar Pérez, Victoria Hellstern, Hansjörg Bäzner, Oliver Ganslandt, Hans Henkes
IntroductionThe endovascular treatment (EVT) of ruptured cerebral aneurysms has been widely adopted after publication of the ISAT. In this study we sought to evaluate the safety and efficacy of the EVT for ruptured aneurysms based on 10-year series from a single centre with coil-first strategy.MethodsAll patients with aneurysmal subarachnoid haemorrhage (aSAH) treated between 2007 and 2016 were retrospectively reviewed and divided according to initial treatment into an EVT and a microsurgical clipping (MSC) group. Clinical and radiological findings at presentation, treatment modalities and any procedural complications were recorded. The angiographic and clinical outcome was compared between the two groups.Results587 patients with aSAH were reviewed (452 EVT, 135 MSC). There were no significant differences in mean age or the Hunt and Hess grades. Parenchymal haemorrhage (PH) was more frequent in the MSC. Procedure related complications of the acute treatment were recorded in 5.5% and 32% in the EVT and MSC, respectively. The rate of retreatment was 21.9% in the EVT and 5.9% in the MSC. Late rehaemorrhage was not observed in either group. There was no significant difference in the clinical outcome between the two treatment groups after adjustment of the other prognostic factors.ConclusionThe majority of ruptured intracranial aneurysms can be managed via an endovascular approach in the acute phase with excellent safety profile and good efficacy. Despite the high rate of reperfusion after primary endovascular approach, retreatment has a very low rate of complications and the rate of recurrent haemorrhage is very low.



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Determination of cesium transfer factors by instrumental neutron activation analysis

Publication date: July 2018
Source:Journal of Environmental Radioactivity, Volume 187
Author(s): G. Bátor, A. Bednár, T.J. Glover, T. Kovács, S. Landsberger
Food-chain models are used to predict radionuclide ingestion after fallout deposition. These models include those transfer processes (soil-to-plant transfer factor(s) [TF], plant-to-animal transfer coefficient(s) [TC] and concentration ratio [CR]) that are likely to be important for radiological assessment. The range of variability for transfer factors for the same plant groups is great, about 4–5 orders of magnitude, which limits their applicability. A better way to determine the best estimate the factors for radiocaesium and other important radionuclides is if the site-specific data are available. Soil, plant and animal samples were collected from a pasture area in Hungary during the vegetation period in 2016. Stable 133Cs concentration was analysed by comparative method with neutron activation analysis (NAA). The comparator and the samples were irradiated in thermal neutron flux 2.55 × 1012 ncm−2s−1 for 2 h (soil) and 6 h (vegetation, animal samples) in the TRIGA Mark II research reactor at the Nuclear Engineering Teaching Laboratory. After an appropriate decay time (12 days) the samples were measured by gamma-spectrometry and analysed. The observed stable caesium TCpm (0.48–0.53) and CRpm (0.41–0.45) were very close to 137Cs factors in the IAEA 2009 Report of 0.49 and 0.54, respectively. This methodology is particularly suitable for the simultaneous study of natural caesium in ecosystem compartments. Consequently, the transfer of stable caesium in a pasture field may be regarded as a useful analogy in predicting the long-term changes of 137Cs affected by site-specific environmental factors.



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Reproduction in the freshwater crustacean Asellus aquaticus along a gradient of radionuclide contamination at Chernobyl

Publication date: 1 July 2018
Source:Science of The Total Environment, Volumes 628–629
Author(s): Neil Fuller, Alex T. Ford, Liubov L. Nagorskaya, Dmitri I. Gudkov, Jim T. Smith
Nuclear accidents such as Chernobyl and Fukushima have led to contamination of the environment that will persist for many years. The consequences of chronic low-dose radiation exposure for non-human organisms inhabiting contaminated environments remain unclear. In radioecology, crustaceans are important model organisms for the development of environmental radioprotection. Previous laboratory studies have demonstrated deleterious effects of radiation exposure on crustacean reproduction. However, no studies have documented the effects of chronic radiation exposure on the reproduction of natural crustacean populations. Based on data from laboratory exposures, we hypothesised that populations of the freshwater isopod Asellus aquaticus exposed to radiation for thirty years at Chernobyl would display reduced reproductive output and altered timing of reproduction. To test this hypothesis, A. aquaticus was collected from six lakes at Chernobyl over two years with total dose rates ranging from 0.06–27.1μGy/h. No significant differences in the fecundity, mass of broods or proportion of reproducing female A. aquaticus were recorded. Significant differences in the body mass of gravid females were recorded suggesting different timings of reproduction, however this was not related to radiation contamination. No significant effect of a range of environmental parameters on A. aquaticus reproduction was recorded. Our data suggests current dose rates at Chernobyl are not causing discernible effects on the reproductive output of A. aquaticus. This study is the first to assess the effects of chronic low-dose radiation exposure on the reproductive output of an aquatic invertebrate at Chernobyl. These findings are consistent with proposed radiological protection benchmarks for the maintenance of wildlife populations and will assist in management of environments impacted by radiation.

Graphical abstract

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Chapter 13 Environmental Radioactivity

Publication date: 2018
Source:Nuclear and Radiochemistry
Author(s): József Kónya, Noémi M. Nagy
In this chapter, the sources and occurrence of radioactive isotopes will be discussed, including natural and anthropogenic radioactive isotopes. The occurrence and circulation of radionuclides in different parts of the geosphere (atmosphere, hydrosphere, and lithosphere) and biosphere (plants, animals, and humans) will be shown. The biological effects of the radioactive isotopes will be demonstrated. The dose units characterizing the irradiations and the mechanism of the biological effects (the physical–chemical–biological reaction chain) will be discussed. The importance of radical formation in the biological effects will be emphasized. The sources of the natural background radiation will be listed: the cosmic ray, the cosmogenic and primordial radionuclides, natural radioactivity due to anthropogenic activity, and artificial radioactive isotopes. The dangerous irradiation ranges, including the stochastic, deterministic, somatic, and genetic effects, will be mentioned. Finally, the principles behind radiation protection regulations will be summarized.



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Bio accumulation of radioactive caesium in marine mammals in the Baltic Sea – Reconstruction of a historical time series

Publication date: 1 August 2018
Source:Science of The Total Environment, Volumes 631–632
Author(s): Sadaf Saremi, Mats Isaksson, Karin C. Harding
Radionuclides from the Chernobyl accident in 1986 still circulate in the Baltic marine ecosystem and activity levels in water, sediments and fish species such as herring and perch are monitored annually. However, the activity levels of radionuclides in marine mammals have only been sporadically reported. Tissue samples from a museum collection were analysed in two species of seals, and the trends over time in activity level of radioactive caesium (Cs-137) after the Chernobyl accident were reconstructed. We also performed a literature review summarizing activity levels in marine mammals world-wide. We found activity concentrations of Cs-137 in Baltic ringed seals and grey seals to be elevated also in the most recent samples, and during the entire study period measurements ranged between 19 and 248 Bq/kg wet weight. A declining trend in time over the last 30 years follow the general trend of decline in activity levels in other Baltic biota. Accumulation was found to be species specific in the two seal species studied, with 9 times higher activity concentration in grey seals compared to herring, and 3.5 times higher in ringed seals compared to herring. We discuss potential paths and rates of bioaccumulation of radioactive caesium in the Baltic Sea including species specific prey choice of the two seal species and estimate life time exposure. The study contributes one important piece of information to predictive models in risk assessments for nuclear accidents.

Graphical abstract

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Index

Publication date: 2018
Source:The Nature and Use of Ecotoxicological Evidence





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Direct measurement of uranium in seawater by inductively coupled plasma mass spectrometry

Publication date: 1 June 2018
Source:Talanta, Volume 183
Author(s): Jixin Qiao, Yihong Xu
A simple method for direct measurement of uranium (238U) in seawater using triple quadrupole inductively coupled plasma mass spectrometry (ICP-MS) was established. The method provides a good analytical performance with respect to detection limit, accuracy, precision and sample throughput. During the method development and application, several interesting facts were observed: 1) Comparison results for reference material using different quantitation approaches indicate that isotope dilution (using 233U) is the most reliable to achieve accurate 238U measurement. The results obtained for direct 238U measurement in 50-fold diluted seawater samples (n = 112) also underline the difference between isotope dilution and internal (or external) standardization. 2) Appropriate dilution of seawater is important to minimize the matrix effect on the ICP-MS measurement and 20–50 dilution is recommended for natural seawater samples. 3) The sensitivity of ICP-MS was observed to increase in the beginning of sample measurement, and then decrease with the continuous injection of samples, which is believed as a consequence of matrix effect from the seawater to the ionization efficiency in the plasma. 4) When measuring samples taken from large volume of seawater stored in immovable containers for relatively long period (i.e., several months), the uranium concentration and salinity data showed slightly increasing trends with the increase of water depth in the container. Therefore, cautions need to be paid in sampling representativeness when performing 238U measurement for such long-term stored large volume samples.

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When a duck is not a duck; a new interdisciplinary synthesis for environmental radiation protection

Publication date: April 2018
Source:Environmental Research, Volume 162
Author(s): Carmel Mothersill, Michael Abend, François Bréchignac, George Iliakis, Nathalie Impens, Munira Kadhim, Anders Pape Møller, Deborah Oughton, Gibin Powathil, Eline Saenen, Colin Seymour, Jill Sutcliffe, Fen-Ru Tang, Paul N. Schofield
This consensus paper presents the results of a workshop held in Essen, Germany in September 2017, called to examine critically the current approach to radiological environmental protection. The meeting brought together participants from the field of low dose radiobiology and those working in radioecology. Both groups have a common aim of identifying radiation exposures and protecting populations and individuals from harmful effects of ionising radiation exposure, but rarely work closely together. A key question in radiobiology is to understand mechanisms triggered by low doses or dose rates, leading to adverse outcomes of individuals while in radioecology a key objective is to recognise when harm is occurring at the level of the ecosystem. The discussion provided a total of six strategic recommendations which would help to address these questions.



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Mobility of 232Th and 210Po in red mud

Publication date: April 2018
Source:Journal of Environmental Radioactivity, Volumes 184–185
Author(s): Miklós Hegedűs, Edit Tóth-Bodrogi, Jácint Jónás, János Somlai, Tibor Kovács
The valorization of industrial by-products such as red mud became a tempting opportunity, but the understanding of the risks involved is required for the safe utilization of these products. One of the risks involved are the elevated levels of radionuclides (in the 100–1300 Bq/kg range for both the 238U and 232 Th decay chains, but usually lower than 1000 Bq/kg, which is the recommended limit for excemption or clearance according to the EU BSS released in 2013) in red mud that can affect human health. There is no satisfactory answer for the utilization of red mud; the main current solution is still almost exclusively disposal into a landfill. For the safe utilization and deposition of red mud, it is important to be able to assess the leaching behaviour of radionuclides. Because there is no commonly accepted measurement protocol for testing the leaching of radionuclides in the EU a combined measurement protocol was made and tested based on heavy metal leaching methods. The leaching features of red mud were studied by methods compliant with the MSZ-21470-50 Hungarian standard, the CEN/TS 14429 standard and the Tessier sequential extraction method for 232Th and 210Po. The leached solutions were taken to radiochemical separation followed by spontaneous deposition for Po and electrodeposition for Th. The 332 ± 33 Bq/kg 232Th content was minimally mobile, 1% became available for distilled water 1% and 6% for Lakanen-Erviö solution; the Tessier extraction showed minimal mobility in the first four steps, while more than 85% remained in the residue. The 210Po measurements had a severe disturbing effect in many cases, probably due to large amounts of iron present in the red mud, from the 310 ± 12 Bq/kg by aqua regia digestion, distilled water mobilized 23%, while Lakanen-Erviö solution mobilized ∼13%. The proposed protocol is suitable for the analysis of Th and Po leaching behaviour.



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Radionuclide transport in the “sediments – water – plants” system of the water bodies at the Semipalatinsk test site

Publication date: April 2018
Source:Journal of Environmental Radioactivity, Volumes 184–185
Author(s): A.K. Aidarkhanova, S.N. Lukashenko, N.V. Larionova, V.V. Polevik
This paper provides research data on levels and character of radionuclide contamination distribution in the «sediments– water – plants » system of objects of the Semipalatinsk test site (STS). As the research objects there were chosen water bodies of man-made origin which located at the territory of "Experimental Field", "Balapan", "Telkem" and "Sary-Uzen" testing sites. For research the sampling of bottom sediments, water, lakeside and water plants was taken. Collected samples were used to determine concentration of anthropogenic radionuclides 90Sr, 239+240Pu, 241Am, 137Cs. The distribution coefficient (Kd) was calculated as the ratio of the content of radionuclides in the sediments to the content in water, and the concentration ratio (FV) was calculated as the ratio of radionuclide content in plants to the content in sediments or soil.



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Late-Holocene vegetation dynamics in response to a changing climate and anthropogenic influences – Insights from stratigraphic records and subfossil trees from southeast Lithuania

Publication date: 1 April 2018
Source:Quaternary Science Reviews, Volume 185
Author(s): Johannes Edvardsson, Miglė Stančikaitė, Yannick Miras, Christophe Corona, Gražyna Gryguc, Laura Gedminienė, Jonas Mažeika, Markus Stoffel
To increase our understanding of long-term climate dynamics and its effects on different ecosystems, palaeoclimatic and long-term botanical reconstructions need to be improved, in particular in underutilized geographical regions. In this study, vegetation, (hydro)climate, and land-use changes were documented at two southeast Lithuanian peatland complexes – Čepkeliai and Rieznyčia – for the Late-Holocene period. The documentation was based on a combination of pollen, plant macrofossils, peat stratigraphic records, and subfossil trees. Our results cover the last two millennia and reveal the existence of moist conditions in Southern Lithuania between 300 and 500 CE and from 950 to 1850 CE. Conversely, changes towards warmer and/or dryer conditions have been recorded in 100, 600, and 750 CE, and since the 1850s. Significant differences with other Baltic proxies prevent deriving a complete and precise long-term reconstruction of past hydroclimatic variability at the regional scale. Yet, our results provide an important cornerstone for an improved understanding of regional climate change, i.e. in a region for which only (i) few detailed palaeobotanical studies exist and which has, in addition, been considered as (ii) an ecologically sensitive region at the interface between the temperate and boreal bioclimatic zones.



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The marine kd and water/sediment interaction problem

Publication date: Available online 7 March 2018
Source:Journal of Environmental Radioactivity
Author(s): R. Periáñez, I. Brovchenko, K.T. Jung, K.O. Kim, V. Maderich
The behavior of marine distribution coefficients is analyzed with the help of numerical experiments and analytical solutions of equations describing kinetic models for uptake/release of radionuclides. The difficulties in measuring true kd in a marine environment perturbed by an external radionuclide source are highlighted. Differences between suspended matter and bed sediment kd are analyzed. The performances of different kinetic models (1-step/2step; single-layer/multi-layer) are studied in model/model and model/experiment comparisons. Implications for the use of models to assess radioactive contamination after an emergency are given; as well as recommendations when kd data are compiled in order to create a useful database.



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Chapter 6 Social Processing of Evidence

Publication date: 2018
Source:The Nature and Use of Ecotoxicological Evidence
Author(s): Michael C. Newman
Previous chapters focused narrowly on evidence generation, processing, and use by individuals. From this point onward, focus will shift to social cognition and co-decision-making by groups responsible for generating or applying evidence. Group decision-making might involve a pair of individuals, small groups with or without formal structure, large networks or groups defined by some common feature or objective, or spontaneously coalescing collections of widely dispersed individuals like those that emerge on the Internet. It might also involve expert panels that combine individual, expert–elicitor pair, and group decision-making features. This chapter examines the sociology giving rise to suboptimal behaviors in pairs or small groups of individuals, suggesting ways of reducing the likelihood of poor decision-making behaviors in groups of ecotoxicologists and risk assessors.



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Radionuclide transfer to wildlife at a ‘Reference site’ in the Chernobyl Exclusion Zone and resultant radiation exposures

Publication date: Available online 28 February 2018
Source:Journal of Environmental Radioactivity
Author(s): N.A. Beresford, C.L. Barnett, S. Gashchak, A. Maksimenko, E. Guliaichenko, M.D. Wood, M. Izquierdo
This study addresses a significant data deficiency in the developing environmental protection framework of the International Commission on Radiological Protection, namely a lack of radionuclide transfer data for some of the Reference Animals and Plants (RAPs). It is also the first study that has sampled such a wide range of species (invertebrates, plants, amphibians and small mammals) from a single terrestrial site in the Chernobyl Exclusion Zone (CEZ). Samples were collected in 2014 from the 0.4 km2 sampling site, located 5 km west of the Chernobyl Nuclear Power complex. We report radionuclide (137Cs, 90Sr, 241Am and Pu-isotopes) and stable element concentrations in wildlife and soil samples and use these to determine whole organism-soil concentration ratios and absorbed dose rates.Increasingly, stable element analyses are used to provide transfer parameters for radiological models. The study described here found that for both Cs and Sr the transfer of the stable element tended to be lower than that of the radionuclide; this is the first time that this has been demonstrated for Sr, though it is in agreement with limited evidence previously reported for Cs.Studies reporting radiation effects on wildlife in the CEZ generally relate observations to ambient dose rates determined using handheld dose meters. For the first time, we demonstrate that ambient dose rates may underestimate the actual dose rate for some organisms by more than an order of magnitude. When reporting effects studies from the CEZ, it has previously been suggested that the area has comparatively low natural background dose rates. However, on the basis of data reported here, dose rates to wildlife from natural background radionuclides within the CEZ are similar to those in many areas of Europe.



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Summary of the proceedings of the International Forum 2017: “Position of interventional radiology within radiology”

Abstract

The International Forum is held once a year by the ESR and its international radiological partner societies with the aim to address and discuss selected topics of global relevance in radiology. In 2017, the issue of the position of interventional radiology (IR) within radiology was analysed. IR is expanding because of the increased patient demand for minimally invasive therapies performed under imaging guidance, and its success in improving patient outcomes, reducing in-hospital stays, reducing morbidity and mortality of treatment in many organs and organ-systems. Despite the many successes of IR, public awareness about it is quite low. IR requires specific training and, in most countries, the majority of interventional radiologists do not dedicate their time completely to IR but perform diagnostic radiology investigations as well. Turf battles in IR are common in many countries. To preserve and keep IR within radiology, it is necessary to focus more on direct and longitudinal patient care. Having beds dedicated to IR within radiology departments is very important to increase clinical involvement of interventional radiologists. IR procedures fit perfectly within "value-based healthcare", but the metrics have to be developed.

Main messages

IR should stay a prominent subspecialty within radiology.

Dedicated IR training pathways are mandatory.

Measures to increase recruitment of young doctors to IR and to increase public awareness of IR are needed.

Beds dedicated to IR within radiology departments are important in order to increase clinical involvement of interventional radiologists.



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Hyperechoic breast images: all that glitters is not gold!

Abstract

Hyperechogenicity is a sign classically reported to be in favour of a benign lesion and can be observed in many types of benign breast lesions such as hamartoma, lipoma, angiolipoma, haemangioma, haematoma, fat necrosis, fibrosis and galactocele, among others. However, some rare malignant breast lesions can also present a hyperechoic appearance. Most of these hyperechoic malignant lesions present other characteristics that are more typically suggestive of malignancy such as posterior shadowing, a more vertical axis or irregular margins that help to guide the diagnosis. Post magnetic resonance imaging, second-look ultrasound may visualise hyperechoic malignant lesions that would not have been identified at first sight and radiologists must know how to recognise these lesions.

Teaching Points

• Some rare malignant breast lesions can present a hyperechoic appearance.

• Malignant lesions present other characteristics that are suggestive of malignancy.

• An echogenic mass with fat density on mammography does not require biopsy.



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Major pancreatic resections: normal postoperative findings and complications

Abstract

Objectives

(1) To illustrate and describe the main types of pancreatic surgery; (2) to discuss the normal findings after pancreatic surgery; (3) to review the main complications and their radiological findings.

Background

Despite the decreased postoperative mortality, morbidity still remains high resulting in longer hospitalisations and greater costs. Imaging findings following major pancreatic resections can be broadly divided into "normal postoperative alterations" and real complications. The former should regress within a few months whereas complications may be life-threatening and should be promptly identified and treated.

Imaging findings

CT is the most effective postoperative imaging technique. MRI and fluoroscopy are used less often and only in specific cases such as assessing the gastro-intestinal function or the biliary tree. The most common normal postoperative findings are pneumobilia, perivascular cuffing, fluid collections, lymphadenopathy, acute anastomotic oedema and stranding of the peri-pancreatic/mesenteric fat. Imaging depicts the anastomoses and the new postoperative anatomy. It can also demonstrate early and late complications: pancreatic fistula, haemorrhage, delayed gastric emptying, hepatic infarction, acute pancreatitis of the remnant, porto-mesenteric thrombosis, abscess, biliary anastomotic leaks, anastomotic stenosis and local recurrence.

Conclusions

Radiologists should be aware of surgical procedures, postoperative anatomy and normal postoperative imaging findings to better detect complications and recurrent disease.

Teaching Points

Morbidity after pancreatic resections is high.

CT is the most effective postoperative imaging technique.

Imaging depicts the anastomoses and the new postoperative anatomy.

Pancreatic fistula is the most common complication after partial pancreatic resection.



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ECR 2018 - BOOK OF ABSTRACTS



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Endometriosis: clinical features, MR imaging findings and pathologic correlation

Abstract

Objective

We illustrate the magnetic resonance imaging (MRI) features of endometriosis.

Background

Endometriosis is a chronic gynaecological condition affecting women of reproductive age and may cause pelvic pain and infertility. It is characterized by the growth of functional ectopic endometrial glands and stroma outside the uterus and includes three different manifestations: ovarian endometriomas, peritoneal implants, deep pelvic endometriosis. The primary locations are in the pelvis; extrapelvic endometriosis may rarely occur. Diagnosis requires a combination of clinical history, invasive and non-invasive techniques. The definitive diagnosis is based on laparoscopy with histological confirmation. Diagnostic imaging is necessary for treatment planning. MRI is as a second-line technique after ultrasound. The MRI appearance of endometriotic lesions is variable and depends on the quantity and age of haemorrhage, the amount of endometrial cells, stroma, smooth muscle proliferation and fibrosis. The purpose of surgery is to achieve complete resection of all endometriotic lesions in the same operation.

Conclusion

Owing to the possibility to perform a complete assessment of all pelvic compartments at one time, MRI represents the best imaging technique for preoperative staging of endometriosis, in order to choose the more appropriate surgical approach and to plan a multidisciplinary team work.

Teaching Points

• Endometriosis includes ovarian endometriomas, peritoneal implants and deep pelvic endometriosis.

• MRI is a second-line imaging technique after US.

• Deep pelvic endometriosis is associated with chronic pelvic pain and infertility.

• Endometriosis is characterized by considerable diagnostic delay.

• MRI is the best imaging technique for preoperative staging of endometriosis.



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Imaging of the scrotum: beyond sonography

Abstract

The aim of this article is to describe the role of second-level imaging techniques after an initial ultrasonography evaluation in the assessment of scrotal diseases. While ultrasonography remains central as the primary imaging modality for the evaluation of pathologic conditions of the scrotum, the role of magnetic resonance imaging continues to evolve: it can actually be valuable as a problem-solving tool when sonographic findings are equivocal or inconclusive. Magnetic resonance imaging of the scrotum may provide accurate detection and characterization of scrotal diseases, well depicting the precise location of scrotal masses (intratesticular or extratesticular) and reliably characterizing benign conditions simulating neoplastic processes, thus preventing unnecessary radical surgery. Advanced magnetic resonance techniques, most of all diffusion weighted imaging and magnetic resonance spectroscopy, play in the meanwhile a more significant role in evaluating scrotal diseases.

Teaching points

• Multiparametric ultrasonography usually represents the initial imaging modality for approaching scrotal diseases.

• MRI is well established as a problem-solving tool for inconclusive sonographic findings.

• Advanced MRI techniques can be successfully applied in scrotal pathology assessment.

• MRI is valuable in differentiating benign conditions from neoplastic processes.

• CT plays a role in trauma assessment and cancer staging alongside PET/CT.



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Granulomatous diseases of the breast and axilla: radiological findings with pathological correlation

Abstract

Objectives

This article reviews our experience and describes the literature findings of granulomatous diseases of the breast and axilla.

Methods

After approval of the Institutional Review Board was obtained, the surgical pathological records from January 2000 to January 2017 were searched for the keyword granulomatous. Clinical, imaging and histology findings were reviewed by both a fellowship-trained radiologist and a breast-imaging consultant radiologist, reviewing 127 patients (age range, 32–86 years; 126 women and 1 man).

Results

Most common causes of granulomatous lesions of the breast and axilla included silicone granulomas 33% (n = 42), fat necrosis 29% (n = 37) and suture granulomas 11% (n = 14). In 16% (n = 20), no cause could be found and clinical history was consistent with idiopathic granulomatous mastitis. Other granulomatous aetiologies included granulomatous infections, sarcoidosis and Sjögren's syndrome. Causes of axillary granulomatous disease were similar to the breast; however, a case of cat-scratch disease was found that only involved the axillary lymph nodes. They can have a variable appearance on imaging and may mimic malignancy with irregular masses seen on mammography, ultrasound and magnetic resonance imaging. Fistulas to the skin and nipple retraction can suggest chronicity and a granulomatous aetiology. Combination of clinical history, laboratory and imaging findings can be diagnostic.

Conclusions

Granulomatous processes of the breast are rare. The diagnosis can, however, be made if there is relevant history (prior trauma, silicone breast implants, lactation), laboratory (systemic or infectious processes) and imaging findings (fistula, nipple retraction). Recognising these entities is important for establishing pathological concordance after biopsy and for preventing unnecessary treatment.

Teaching points

  • Breast granulomatous are rare but can mimic breast carcinoma on imaging

  • Imaging with clinical and laboratory findings can correctly diagnosis specific granulomatous breast diseases

  • Recognition of the imaging findings allows appropriate pathological concordance and treatment



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Diffusion weighted imaging (DWI) and apparent diffusion coefficient (ADC) values for detection of malignant vertebral bone marrow lesions

Malignant spinal bone marrow disorders are one of the major causes of significant morbidity and reduction in quality of life in oncological patients. Thus, the characterization of these conditions is of crucial importance in the management of these patients.

Magnetic resonance (MR) imaging plays a vital role in differentiation between benign and malignant spinal bone marrow disorders. However, morphological imaging features, based on T1 and T2 relaxation properties, might fail in differentiating between these conditions because signal characteristics may overlap. Quantitative MR imaging based on diffusion weighted imaging (DWI) and apparent diffusion coefficient (ADC) values has been proved to help in defining the nature of the lesion. The aims of this paper were: to review basic principles of DWI technique and ADC maps, to describe DWI and ADC maps appearances of normal vertebral bone marrow briefly, to discuss the DWI and ADC maps characteristics in vertebral malignant lesions, to provide indications for differential diagnosis between malignant and benign lesions.

L'articolo Diffusion weighted imaging (DWI) and apparent diffusion coefficient (ADC) values for detection of malignant vertebral bone marrow lesions sembra essere il primo su European Review.



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Primary neoplasms of the small bowel at CT: a pictorial essay for the clinician

OBJECTIVE: Primary small intestinal neoplasms are uncommon tumors that are often small and difficult to identify. The aim of this paper is to describe CT technique and features in detecting and characterizing the tumors of the small bowel.

MATERIALS AND METHODS: This paper focuses on radiological characteristics of benign and malignant primary neoplasms of the small bowel at CT, with special reference to multidetector-CT techniques, type and modality of administration of contrast agents (by oral route or CT-enterography and by nasojejunal tube or CT-enteroclysis). This paper will also provide pictures and description of CT findings of benign and malignant primary neoplasms using examples of CT-enterography and CT-enteroclysis.

RESULTS: Among CT modalities, CT-enterography has the advantage of defining the real extension of wall lesions, possible transmural extension, the degree of mesenteric involvement and remote metastasis. Other useful modalities for the diagnosis of such lesions like capsule endoscopy and enteroscopy, provide important information but limited to mucosal changes with lower accuracy on extension and bowel wall involvement or submucosal lesions.

CONCLUSIONS: Multidetector-CT, performed after distension of the small bowel with oral contrast material and intravenous injection of iodinated contrast material, is a useful method for the diagnosis and staging of small bowel neoplasms.

L'articolo Primary neoplasms of the small bowel at CT: a pictorial essay for the clinician sembra essere il primo su European Review.



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Clinical use of cardiac PET/MRI: current state-of-the-art and potential future applications

Abstract

Combined PET/MRI is a novel imaging method integrating the advances of functional and morphological MR imaging with PET applications that include assessment of myocardial viability, perfusion, metabolism of inflammatory tissue and tumors, as well as amyloid deposition imaging. As such, PET/MRI is a promising tool to detect and characterize ischemic and non-ischemic cardiomyopathies. To date, the greatest benefit may be expected for diagnostic evaluation of systemic diseases and cardiac masses that remain unclear in cardiac MRI, as well as for clinical and scientific studies in the setting of ischemic cardiomyopathies. Diagnosis and therapeutic monitoring of cardiac sarcoidosis has the potential of a possible 'killer-application' for combined cardiac PET/MRI. In this article, we review the current evidence and discuss current and potential future applications of cardiac PET/MRI.



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Three-dimensional visualization of internal vertebral venous plexuses relative to dural sac and spinal nerve root of spinal canal stenosis using MRI

Abstract

Purpose

The aim of this study was to introduce a new method of producing three-dimensional (3D) images of vertebral venous plexuses (VVPs) by 3D-MRI with and without contrast media, to identify pathoanatomical features that might accelerate or modify spinal canal stenosis.

Methods

We used a 1.5-T MRI unit with two different 3D sequences with and without contrast media. Multi planar reconstruction (MPR) images of VVPs could be obtained by volume image subtraction methods with a workstation for dural sac from whole 3D volume MPR without contrast media, using images before and after gadoteridol injection. Three patients with degenerative lumbar spine disease and one with cervical ossification of the posterior longitudinal ligament (OPLL) were studied with and without contrast media. As three patients underwent operations, we investigated intraoperative microscopic findings, and compared VVP images.

Results

Abundant components of internal VVPs were identified on MRI in correlation with neural tissues such as dura and nerve roots.

Conclusions

Using 3D MRI without and with gadoteridol, we can evaluate morphological changes in VVP under degenerative spinal conditions. The MR anatomy of VVPs of the spine is important, as it has been implicated in many pathophysiological mechanisms and may also cause pitfalls in MRI.



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Pathology and images of radiation-induced hepatitis: a review article

Abstract

Recent advances in highly conformal radiotherapies greatly extend the indications for radiotherapy of liver tumors. However, because of poor tolerance to hepatic radiation, estimation of the intensity of irradiation of the liver is important, particularly for a cirrhotic liver. Knowledge of radiation-induced hepatitis is important for understanding how to optimize hepatic radiation therapy. Pathological changes of the irradiated liver, which include perivenular fibrosis, sinusoidal obstruction, and damage to Kupffer cells and hepatocytes, can be visualized using clinical imaging techniques. This review article discusses and illustrates the pathological and radiological changes of hepatic tumors and the surrounding parenchyma of the irradiated liver.



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Deep learning with convolutional neural network in radiology

Abstract

Deep learning with a convolutional neural network (CNN) is gaining attention recently for its high performance in image recognition. Images themselves can be utilized in a learning process with this technique, and feature extraction in advance of the learning process is not required. Important features can be automatically learned. Thanks to the development of hardware and software in addition to techniques regarding deep learning, application of this technique to radiological images for predicting clinically useful information, such as the detection and the evaluation of lesions, etc., are beginning to be investigated. This article illustrates basic technical knowledge regarding deep learning with CNNs along the actual course (collecting data, implementing CNNs, and training and testing phases). Pitfalls regarding this technique and how to manage them are also illustrated. We also described some advanced topics of deep learning, results of recent clinical studies, and the future directions of clinical application of deep learning techniques.



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Acknowledgment



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Global and Japanese regional variations in radiologist potential workload for computed tomography and magnetic resonance imaging examinations

Abstract

Purpose

To investigate the global variation in radiologist potential workload for CT and MRI examinations, and the regional variation in potential workload and extent of radiologists' involvement in CT and MRI examinations in Japan.

Methods

"Radiologist potential workload" was defined as the annual number of CT plus MRI examinations divided by the total number of diagnostic radiologists. The extent of radiologists' involvement was measured as the proportion of CT and MRI examinations to which "Added-fees for Radiological Managements on Imaging-studies (ARMIs)" were applied among eligible examinations. Maximum variation was computed as the ratio of the highest-to-lowest values among the countries or Japanese prefectures.

Results

The radiologist potential workload in Japan was 2.74–4.17 times higher than those in other countries. A maximum prefecture-to-prefecture variation was 3.88. The average percentage of CT plus MRI examinations with ARMI applied was 43.3%, with a maximum prefecture-to-prefecture variation of 3.97. Prefectures with more radiologists tended to have a higher extent of radiologists' involvement.

Conclusions

Japan had a far greater radiologist potential workload compared with other countries, with a large regional variation among prefectures. Prefectures with more radiologists tended to have a higher extent of radiologists' involvement in CT and MRI examinations.



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Utility of second-generation single-energy metal artifact reduction in helical lung computed tomography for patients with pulmonary arteriovenous malformation after coil embolization

Abstract

Purpose

The quality of images acquired using single-energy metal artifact reduction (SEMAR) on helical lung computed tomography (CT) in patients with pulmonary arteriovenous malformation (PAVM) after coil embolization was retrospectively evaluated.

Materials and methods

CT images were reconstructed with and without SEMAR. Twenty-seven lesions [20 patients (2 males, 18 females), mean age 61.2 ± 11.0 years; number of embolization coils, 9.8 ± 5.0] on contrast-enhanced CT and 18 lesions of non-enhanced lung CT concurrently performed were evaluated. Regions of interest were positioned around the coils and mean standard deviation value was compared as noise index. Two radiologists visually evaluated metallic coil artifacts using a four-point scale: 4 = minimal; 3 = mild; 2 = strong; 1 = extensive.

Results

Noise index was significantly improved with SEMAR versus without SEMAR (median [interquartile range]; 194.4 [161.6–211.9] Hounsfield units [HU] vs. 243.9 [220.4–286.0] HU; p < 0.001). Visual score was significantly improved with SEMAR versus without SEMAR (Reader 1, 3 [3] vs.1 [1]; Reader 2, 3 [3] vs.1 [1]; p < 0.001). Significant differences were similarly demonstrated on lung CT (p < 0.001).

Conclusion

SEMAR provided clear chest CT images in patients who underwent PAVM coil embolization.



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Assessment of Low-Grade Meniscal and Cartilage Damage of the Knee at 7 T: A Comparison to 3 T Imaging With Arthroscopic Correlation

Objectives The aim of this study was to compare the assessment of low-grade meniscal tears and cartilage damage in ultrahigh-field magnetic resonance imaging (MRI) at 7 T to routine clinical MRI at 3 T. Materials and Methods This study was approved by the local ethics committee, and written informed consent was obtained from each patient. Forty-one patients with suspected meniscal damage or mild osteoarthritis (Kellgren-Lawrence score, 0–2) received 7 T as well as routine clinical 3 T consecutively. The imaging protocol at both field strengths consisted of PD-weighted imaging with more than doubled resolution at 7 T. Images were read blinded regarding field strength and patient characteristics by 3 readers with different experience in musculoskeletal MRI (3 years, 6 years, and 10 years) according to a modified whole-organ MRI score of the knee in osteoarthritis and the Score of the International Cartilage Repair Society. Arthroscopic reports as a criterion standard were available for 12 patients. A multifactorial mixed model analysis was performed. Results The mean cumulated diagnostic score at 7 T was significantly closer to the criterion standard compared with 3 T in patients where criterion standard was available (P

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Pulmonary Function Diagnosis Based on Respiratory Changes in Lung Density With Dynamic Flat-Panel Detector Imaging: An Animal-Based Study

Objectives The aims of this study were to address the relationship between respiratory changes in image density of the lungs and tidal volume, to compare the changes between affected and unaffected lobes, and to apply this new technique to the diagnosis of atelectasis. Materials and Methods Our animal care committee approved this prospective animal study. Sequential chest radiographs of 4 pigs were obtained under respiratory control with a ventilator using a dynamic flat-panel detector system. Porcine models of atelectasis were developed, and the correlation between the tidal volume and changes in pixel values measured in the lungs were analyzed. The mean difference in respiratory changes in pixel values between both lungs was tested using paired t tests. To facilitate visual evaluation, respiratory changes in pixel values were visualized in the form of a color display, that is, as changes in color scale. Results Average pixel values in the lung regions changed according to forced respiration. High linearity was observed between changes in pixel values and tidal volume in the normal models (r = 0.99). Areas of atelectasis displayed significantly reduced changes in pixel values (P

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Phenotypic Multiorgan Involvement of Subclinical Disease as Quantified by Magnetic Resonance Imaging in Subjects With Prediabetes, Diabetes, and Normal Glucose Tolerance

Introduction Detailed mechanisms in the pathophysiology of diabetes disease are poorly understood, but structural alterations in various organ systems incur an elevated risk for cardiovascular events and adverse outcome. The aim of this study was to compare multiorgan subclinical disease phenotypes by magnetic resonance (MR) imaging to study differences between subjects with prediabetes, diabetes, and normal controls. Materials and Methods Subjects without prior cardiovascular disease were enrolled in a prospective case-control study and underwent multiorgan MR for the assessment of metabolic and arteriosclerotic alterations, including age-related white matter changes, hepatic proton density fat fraction, visceral adipose tissue volume, left ventricular remodeling index, carotid plaque, and late gadolinium enhancement. Magnetic resonance features were summarized in a phenotypic-based score (range, 0–6). Univariate, multivariate correlation, and unsupervised clustering were performed. Results Among 243 subjects with complete multiorgan MR data sets included in the analysis (55.6 ± 8.9 years, 62% males), 48 were classified as subjects with prediabetes and 38 as subjects with diabetes. The MR phenotypic score was significantly higher in subjects with prediabetes and diabetes as compared with controls (mean score, 3.00 ± 1.04 and 2.69 ± 0.98 vs 1.22 ± 0.98, P

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Intravenous Calcium-/Zinc-Diethylene Triamine Penta-Acetic Acid in Patients With Presumed Gadolinium Deposition Disease: A Preliminary Report on 25 Patients

Objectives The aim of this study was to report the use of intravenous calcium (Ca)-/zinc (Zn)-diethylene triamine penta-acetic acid (DTPA) for the treatment of 25 symptomatic patients diagnosed with gadolinium deposition disease (GDD). Materials and Methods Written informed consent was obtained. Twenty-five patients (18 women; mean age, 46.8 ± 15.3 years) with a diagnosis of GDD were included. All patients had received at least 1 administration of a gadolinium (Gd)-based contrast agent. Patients received 3 treatment sessions with Ca-/Zn-DTPA, 15 with treatments spaced 1 month apart, and 10 with treatments spaced 1 week apart. In all cases, every treatment consisted of an application of Ca-DTPA and Zn-DTPA separated by 24 hours. Measurements of 24-hour urine Gd content before dosing and on the first and second days of therapy were performed. Symptomatic improvement of patients was determined by use of a 10-point scale of patient symptoms. Serum electrolytes were quantified. Results Gadolinium content increased in the urine, with an overall mean of 30.3-fold increase in the monthly regimen (P

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Continuous Hepatic Arterial Multiphase Magnetic Resonance Imaging During Free-Breathing

Purpose The aim of this study was to evaluate the feasibility of a prototype volume-interpolated breath-hold examination (VIBE) sequence using compressed sensing (VIBECS) for rapid multiphase arterial magnetic resonance imaging (MRI) at different temporal resolution during free-breathing in comparison with a conventional breath-hold approach (VIBESTD). Material and Methods A total of 40 patients with liver malignancies were prospectively included in this study and underwent contrast-enhanced liver MRI at 1.5 T to evaluate the performance of VIBECS for rapid arterial multiphase imaging. An additional 40 patients examined with a VIBESTD were included serving as standard of reference. The VIBECS study cohort was subdivided into 2 groups (each n = 20). In both groups, VIBECS was continuously acquired for 60 seconds starting with the contrast agent administration (group A, temporal resolution 4 seconds; group B, temporal resolution 8 seconds). Subsequently, the time point with the subjectively best image quality was selected and defined as hepatic arterial dominant (HAD) phase. Overall image quality, lesion conspicuity, vessel contrast, and artifacts of HAD phase were assessed by 2 radiologists independently on a 5-point Likert scale (5 = excellent) and compared with arterial phase images of VIBESTD. In addition, signal attenuation/time curves of VIBECS were plotted for each patient to quantify the hepatic arterial enhancement. Results No patients were excluded and all HAD phases were reliably recorded in the investigated VIBECS cohort. Most commonly, HAD was observed at the ninth time point (36 seconds after intravenous contrast injection) in group A and at the fifth time point (40 seconds after intravenous contrast injection) in group B. Timing with VIBESTD was only adequate in 65% (26/40). Image quality, lesion conspicuity, and vessel contrast were good to excellent without significant differences between both VIBECS groups (P ≥ 0.2) and with significantly higher reading scores as compared with VIBESTD with respect to lesion conspicuity (P ≤ 0.006) and image quality (group B; P

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Dual-Energy Computed Tomography–Based Display of Bone Marrow Edema in Incidental Vertebral Compression Fractures: Diagnostic Accuracy and Characterization in Oncological Patients Undergoing Routine Staging Computed Tomography

Purpose The aim of this study was to evaluate the diagnostic performance of virtual noncalcium (VNCa) dual-energy computed tomography (DECT) reconstructions enabling visualization of bone marrow edema for characterization of incidental thoracolumbar compression fractures in routine thoracoabdominal staging computed tomography (CT). Materials and Methods We retrospectively analyzed 51 oncological patients without suspected fracture or indicative complaints presenting at least 1 thoracolumbar compression fracture on routine thoracoabdominal staging DECT who had been examined between October 2015 and June 2017 using third-generation dual-source CT, had a previous CT within 3 months before, and also had undergone additional magnetic resonance imaging within 14 days, which served as the standard of reference. Three independent and blinded radiologists initially evaluated all vertebrae on conventional grayscale DECT series; after at least 8 weeks, observers reevaluated all cases using grayscale and color-coded VNCa DECT images. The age of each fracture was determined as either acute, chronic, or inconclusive. Specificity, sensitivity, and intraobserver and interobserver agreements were calculated taking into account clustering. Results A total of 98 vertebral compression fractures were detected in 51 patients (20 women, 31 men; median of 1 fracture per patient). The reference standard defined 45 as acute and 53 as chronic. For identification of only acute fractures (cutoff 1), the combination of grayscale and VNCa image series showed a higher sensitivity (91% vs 47%; P

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Breakthrough Reactions to Gadobenate Dimeglumine

Purpose The aim of this study was to determine the severity of breakthrough reactions to gadobenate dimeglumine in patients premedicated with a 13-hour premedication regimen. Methods Institutional review board approval was obtained and informed consent waived for this Health Insurance Portability and Accountability Act–compliant retrospective cohort study. All acute allergic-like reactions to gadobenate dimeglumine from 11/1/2008 to 1/31/2016 were identified. Of these, 19 allergic-like reactions followed 13-hour premedication: 150 mg prednisone and 50 mg diphenhydramine (ie, "breakthrough reactions"). Reasons for premedication, risk factors, index reaction characteristics, and breakthrough reaction characteristics were catalogued. Reaction severities were assigned using American College of Radiology guidelines. Severities of breakthrough (n = 19) and nonbreakthrough reactions (n = 97) were compared with the Cochran-Armitage test for trend. Results Premedication was most commonly given (63% [12/19]) for a previous allergic-like reaction to gadolinium-based contrast material (GBCM); in 37% (7/19), it was given for a different risk factor. In those premedicated for a previous allergic-like reaction to GBCM of known severity (n = 9), the breakthrough reaction severity was the same as index reaction severity in 56% (5/9), less severe in 11% (1/9), and of greater severity in 33% (3/9). Two severe breakthrough reactions occurred; both were in subjects premedicated for risk factors other than a previous GBCM reaction. No subjects died. Five subjects were reexposed to GBCM a total of 9 times; no repeat breakthrough reactions occurred. Breakthrough reactions were more severe than nonbreakthrough reactions (P = 0.046), but the level of significance was borderline. Conclusion Premedication does not eliminate severe reactions to gadobenate dimeglumine. Breakthrough reactions to gadobenate dimeglumine can be of greater severity than index reactions. Received for publication December 1, 2017; and accepted for publication, after revision, January 10, 2018. Conflicts of interest and sources of funding: none declared. Correspondence to: Matthew S. Davenport, MD, 1500 E Medical Center Dr B2-A209P, Ann Arbor MI 48109. E-mail: matdaven@med.umich.edu. Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.

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Improved Detection of Foreign Bodies on Radiographs Using X-ray Dark-Field and Phase-Contrast Imaging

Purpose The aim of this study was to investigate whether the detection of foreign bodies can be improved using dark-field and phase-contrast radiography compared with conventional (transmission) radiographs. Materials and Methods Experiments were performed using ex vivo pig paws, which were prepared with differently sized foreign bodies of metal, wood, and glass (n = 10 each). Paws without foreign bodies served as controls (n = 30). All images were acquired using an experimental grating-based large object radiography system. Five blinded readers (second- to fourth-year radiology residents) were asked to assess the presence or absence of any foreign body. Sensitivity and specificity for the detection of metal, wood, glass, and any foreign body were calculated and compared using McNemar test and generalized linear mixed models. Results Sensitivity for the detection of metal foreign bodies was 100% for all readers and image combinations. The sensitivity for the detection of wooden foreign bodies increased from 2% for transmission images to 78% when dark-field images were added (P

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Magnetization Transfer Ratio in Peripheral Nerve Tissue: Does It Depend on Age or Location?

Background and Purpose Magnetization transfer contrast imaging provides indirect information on the concentration of "bound" water protons and their interactions with "free" water molecules. The purpose of this study is to analyze location- and age-dependent changes in the magnetization transfer ratio (MTR) of lower extremity nerves. Materials and Methods Ten younger (20–32 years) and 5 older (50–63 years) healthy volunteers underwent magnetization transfer contrast imaging at 3 Tesla Two 3-dimensional gradient echo sequences with and without an off-resonance saturation pulse (repetition time: 58 milliseconds; echo time: 2.46 milliseconds; band width: 530 Hz/Px; flip angle: α = 7°) were acquired at 3 different locations covering the proximal thigh to the distal lower leg in the group of younger volunteers and at 2 different locations covering the proximal to distal thigh in the group of older volunteers. Sciatic and tibial nerve regions of interest (ROIs) were manually drawn and additional ROIs were placed in predetermined muscles. Magnetization transfer ratios were extracted from respective ROIs and calculated for each individual and location. Results In young volunteers, mean values of nerve and muscle MTR were not different between the proximal thigh (nerve: 20.34 ± 0.91; muscle: 31.71 ± 0.29), distal thigh (nerve: 19.90 ± 0.98; P = 0.76; muscle: 31.53 ± 0.69; P = 0.87), and lower leg (nerve: 20.82 ± 1.07; P = 0.73; muscle: 32.44 ± 1.11; P = 0.51). An age-dependent decrease of sciatic nerve MTR was observed in the group of older volunteers (16.95 ± 1.2) compared with the group of younger volunteers (20.12 ± 0.65; P = 0.019). Differences in muscle MTR were not significant between older (31.01 ± 0.49) and younger (31.62 ± 0.37; P = 0.20) volunteers. Conclusion The MTR of lower extremity nerves shows no proximal-to-distal gradient in young healthy volunteers but decreases with age. For future studies using MTR in peripheral nerve disorders, these findings suggest that referencing magnetization transfer contrast values in terms of age, but not anatomical nerve location is required. Received for publication December 4, 2017; and accepted for publication, after revision, January 18, 2018. Conflicts of interest and source of funding: Dr Kollmer was supported by a research grant from Alnylam Pharmaceuticals. Prof Heiland and Prof Bendszus were supported by the German Research Foundation (SFB 1118). For the remaining authors, none were declared. Correspondence to: Jennifer Kollmer, MD, Department of Neuroradiology, Heidelberg University Hospital, Im Neuenheimer Feld 400, D-69120 Heidelberg, Germany. E-mail: jennifer.kollmer@med.uni-heidelberg.de. Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.

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Advocating the Development of Next-Generation High-Relaxivity Gadolinium Chelates for Clinical Magnetic Resonance

The question of improved relaxivity, and potential efficacy therein, for a next-generation of magnetic resonance gadolinium chelates with extracellular distribution and renal excretion, which could also be viewed from the perspective of dose, is addressed on the basis of historical development, animal experimentation, and human trials. There was no systematic evaluation that preceded the choice of 0.1 mmol/kg as the standard dose for human imaging with the gadolinium chelates. In part, this dose was chosen owing to bloodwork abnormalities seen in phase I and phase II studies. Animal investigations and early clinical trials demonstrated improved lesion detectability at higher doses in the brain, liver, and heart. By designing an agent with substantially improved relaxivity, higher enhancement equivalent to that provided with the conventional gadolinium agents at high dose could be achieved, translating to improved diagnosis and, thus, clinical care. Implicit in the development of such high-relaxivity agents would be stability equivalent to or exceeding that of the currently approved macrocyclic agents, given current concern regarding dechelation and gadolinium deposition in the brain, skin, and bone with the linear agents that were initially approved. Development of such next-generation agents with a substantial improvement in relaxivity, in comparison with the current group of approved agents, with a 2-fold increase likely achievable, could lead to improved lesion enhancement, characterization, diagnosis, and, thus, clinical efficacy. Received for publication November 6, 2017; and accepted for publication, after revision, January 14, 2018. Conflicts of interest and sources of funding: Partial support provided by an unrestricted educational grant from Bayer Healthcare. Correspondence to: Val M. Runge, MD, University Hospital of Bern, Inselpital, Freiburgstrasse 10 (INO B 106), 3010 Bern, Switzerland. Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.

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Characterization of Small Renal Tumors With Magnetic Resonance Elastography: A Feasibility Study

Objectives The aim of this study was to explore the feasibility of magnetic resonance elastography (MRE) for characterizing indeterminate small renal tumors (SRTs) as part of a multiparametric magnetic resonance (MR) imaging protocol. Materials and Methods After institutional review board approval and informed consent were obtained, 21 prospective adults (15 men; median age, 55 years; age range, 25–72 years) with SRT were enrolled. Tumors (2–5 cm Ø) were imaged using 3-directional, gradient echo MRE. Viscoelastic parametric maps (shear wave velocity [c] and attenuation [α]) were analyzed by 2 independent radiologists. Interobserver agreement (Bland-Altman statistics and intraclass correlation coefficients) was assessed. Anatomical T2-weighted, dynamic contrast-enhanced (DCE) and diffusion sequences completed the acquisition protocol. Imaging parameters were compared between groups (Mann-Whitney U test). Results Quality of MRE was good in 18 cases (mean nonlinearity

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Sigmoid sinus dehiscence and suspected idiopathic intracranial hypertension in pulsatile tinnitus?



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