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Abstract In Italy, several types of influenza vaccine are on the market. Available evidence suggests that no single vaccine type is universally appropriate; rather, different types may be more appropriate for different population strata. However, while the concept of appropriateness/preferential use of single vaccines is usually adopted at the central level, little is known about the attitudes of physicians on the matter. A pilot survey of Italian physicians (N = 372) revealed that most (about 90%) were aware that the available vaccines were different, and that particular vaccines were more appropriate for specific groups. The availability of explicit guidelines on which vaccine to administer to a given population group was deemed desirable by 93.2% of respondents. The results were consistent with the 2018 Italian and UK normative documents, which indicate adjuvanted vaccines as the most appropriate choice for the elderly, and quadrivalent formulations for the younger age-classes. Public health policy implications are discussed. [ABSTRACT FROM AUTHOR]

Background: European countries use a wide variety of surveillance systems and prevention measures for viral hepatitis. Each system is adapted to the local situation and an overview was never mapped out at European level. The EUROHEP.NET Project is a European Commission-funded feasibility study for a future network on surveillance and prevention of vaccine-preventable hepatitis. We analysed the measurement and reporting of burden of disease for hepatitis A (HA) and B (HB) in the participating countries. Methods: Twenty-eight countries were invited to participate in this study. An online survey was available from the project's website (www.eurohep.net). The questions concerned the organisation of the surveillance system, case definition, burden of disease, epidemiology, and vaccination strategies. The responses on data sources and the numeric data related to burden of disease for HA for the period 1997-2001 were analysed. Results: Twenty-two countries completed the survey for hepatitis A. Data on total number of hospitalisations and deaths were available from 17 and 18 countries, respectively, although sometimes not complete. Data on hospitalisation days, number of liver transplants and proportion of these due to HAV were often not available. Conclusion: Surveillance systems on burden of disease for hepatitis A show a wide diversity among the participating countries. The introduction of a standardised system of data collection at the European Union level according to ICD-10 but respecting the local current practices is a primary need, especially for data that should be collected in all countries, like hospitalisation and mortality. A link to surveillance databases is also strongly recommended. [ABSTRACT FROM AUTHOR]

Objective: The aim of the current study was, first, to assess the coronary artery calcium (CAC) scoring potential of spectral photon-counting CT (SPCCT) in comparison with computed tomography (CT) for routine clinical protocols. Second, improved CAC detection and quantification at reduced slice thickness were assessed. Methods: Raw data was acquired and reconstructed with several combinations of reduced slice thickness and increasing strengths of iterative reconstruction (IR) for both CT systems with routine clinical CAC protocols for CT. Two CAC-containing cylindrical inserts, consisting of CAC of different densities and sizes, were placed in an anthropomorphic phantom. A specific CAC was detectable when 3 or more connected voxels exceeded the CAC scoring threshold of 130 Hounsfield units (HU). For all reconstructions, total CAC detectability was compared between both CT systems. Significant differences in CAC quantification (Agatston and volume scores) were assessed with Mann-Whitney U tests. Furthermore, volume scores were compared with the known CAC physical. Results: CAC scores for routine clinical protocols were comparable between SPCCT and CT. SPCCT showed 34% and 4% higher detectability of CAC for the small and large phantom, respectively. At reduced slice thickness, CAC detection increased by 142% and 169% for CT and SPCCT, respectively. In comparison with CT, volume scores from SPCCT were more comparable with the physical volume of the CAC. Conclusion: CAC scores using routine clinical protocols are comparable between conventional CT and SPCCT. The increased spatial resolution of SPCCT allows for increased detectability and more accurate CAC volume estimation. Key Points: • Coronary artery calcium scores using routine clinical protocols are comparable between conventional CT and spectral photon-counting CT. • In comparison with conventional CT, increased coronary artery calcium detectability was shown for spectral photon-counting CT due to increased spatial resolution. • Volumes scores were more accurately determined with spectral photon-counting CT. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this work is to show a new scintigraphic device able to change automatically the length of its collimator in order to adapt the spatial resolution value to gamma source distance. This patented technique replaces the need for collimator change that standard gamma cameras still feature. Monte Carlo simulations represent the best tool in searching new technological solutions for such an innovative collimation structure. They also provide a valid analysis on response of gamma cameras performances as well as on advantages and limits of this new solution. Specifically, Monte Carlo simulations are realized with GEANT4 (GEometry ANd Tracking) framework and the specific simulation object is a collimation method based on separate blocks that can be brought closer and farther, in order to reach and maintain specific spatial resolution values for all source-detector distances. To verify the accuracy and the faithfulness of these simulations, we have realized experimental measurements with identical setup and conditions. This confirms the power of the simulation as an extremely useful tool, especially where new technological solutions need to be studied, tested and analyzed before their practical realization. The final aim of this new collimation system is the improvement of the SPECT techniques, with the real control of the spatial resolution value during tomographic acquisitions. This principle did allow us to simulate a tomographic acquisition of two capillaries of radioactive solution, in order to verify the possibility to clearly distinguish them. [ABSTRACT FROM AUTHOR]

Abstract: The H8500 PhotoMultiplier Tube (PMT) from Hamamatsu has been used in the last years to assemble several scintigraphic devices in order to achieve high-resolution gamma cameras. If the detector is coupled to discrete scintillator with millimetric pixel size, the resulting charge distribution that emerges is not properly sampled by its anodes (6×6mm2). The new position sensitive PMT H9500, with its 3×3mm2 anodes, allows a better charge distribution sampling, improving both spatial resolution and linearity of the system. In this paper, we investigate the imaging performances of the H9500 PMT coupled with a CsI(Tl) array having 1mm pixel size and compare the results with the same scintillator coupled with H8500 PMT. A portable imaging system named HiRIS (High-Resolution Imaging System) was then realized using a miniaturized readout electronic. Thanks to its lightness, it can be easily used in Medical Imaging. We used HiRIS, together with a rotating system, to carry out a tomographic reconstruction of the biodistribution of a radiopharmaceutical in rats. [Copyright &y& Elsevier]