NEGATIVE SYNERGISM BETWENN THE COMBINATION OF STEROID AND LOW MOLECULAR WEIGHT HEPARIN (LMWH) ON BONE METABOLISM, IN PATIENTS TREATED FOR LYMPHOMA

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Experimental optimization of the energy for breast-CT with synchrotron radiation

Breast Computed Tomography (bCT) is a three-dimensional imaging technique that is raising interest among radiologists as a viable alternative to mammographic planar imaging. In X-rays imaging it would be desirable to maximize the capability of discriminating different tissues, described by the Contrast to Noise Ratio (CNR), while minimizing the dose (i.e. the radiological risk). Both dose and CNR are functions of the X-ray energy. This work aims at experimentally investigating the optimal energy that, at fixed dose, maximizes the CNR between glandular and adipose tissues. Acquisitions of both tissue-equivalent phantoms and actual breast specimens have been performed with the bCT system implemented within the Syrma-3D collaboration at the Syrmep beamline of the Elettra synchrotron (Trieste). The experimental data have been also compared with analytical simulations and the results are in agreement. The CNR is maximized at energies around 26–28 keV. These results are in line with the outcomes of a previously presented simulation study which determined an optimal energy of 28 keV for a large set of breast phantoms with different diameters and glandular fractions. Finally, a study on photon starvation has been carried out to investigate how far the dose can be reduced still having suitable images for diagnostics

Brixsino High-Flux Dual X-Ray and THz Radiation Source Based on Energy Recovery Linacs

We present the conceptual design of a compact light source named BriXSinO. BriXSinO was born as demonstrator of the Marix project, but it is also a dual high flux radiation source Inverse Compton Source (ICS) of X-ray and Free-Electron Laser of THz spectral range radiation conceived for medical applications and general applied research. The accelerator is a push-pull CW-SC Energy Recovery Linac (ERL) based on superconducting cavities technology and allows to sustain MW-class beam power with almost just one hundred kW active power dissipation/consumption. ICS line produces 33 keV monochromatic X-Rays via Compton scattering of the electron beam with a laser system in Fabry-Pérot cavity at a repetition rate of 100 MHz. The THz FEL oscillator is based on an undulator imbedded in optical cavity and generates THz wavelengths from 15 to 50 micron

MariX, an advanced MHz-class repetition rate X-ray source for linear regime time-resolved spectroscopy and photon scattering

The need of a fs-scale pulsed, high repetition rate, X-ray source for time-resolved fine analysis of matter (spectroscopy and photon scattering) in the linear response regime is addressed by the conceptual design of a facility called MariX (Multi-disciplinary Advanced Research Infrastructure for the generation and application of X-rays) outperforming current X-ray sources for the declared scope. MariX is based on the original design of a two-pass two-way superconducting linear electron accelerator, equipped with an arc compressor, to be operated in CW mode (1 MHz). MariX provides FEL emission in the range 0.2–8 keV with 108 photons per pulse ideally suited for photoelectric effect and inelastic X-ray scattering experiments. The accelerator complex includes an early stage that supports an advanced inverse Compton source of very high-flux hard X-rays of energies up to 180 keV that is well adapted for large area radiological imaging, realizing a broad science programme and serving a multidisciplinary user community, covering fundamental science of matter and application to life sciences, including health at preclinical and clinical level

Signal-to-Noise gain at variable random fraction in TOF PET

Time of Flight (TOF) Positron Emission Tomography (PET) produces an improvement in signal-to-noise ratio (SNR) over conventional non-TOF reconstruction. This improvement increases with the size of the patient and with better coincidence time resolution of the system. As a first approximation in TOF PET reconstruction, this gain in SNR is independent of the scatter and randoms components of the total signal. On the other hand, recently a model has been proposed in which the SNR gain of TOF PET vs. conventional PET is a growing function of the randoms ratio (number of random coincidences divided by number of trues plus scattered coincidences). This would provide an additional advantage of TOF PET reconstruction over conventional PET, particularly in the presence of a large randoms ratio. In this work we show measurements with a NEMA image quality phantom on a Siemens Biograph mCT TOF PET/CT scanner, which confirm the prediction of the model for filtered back projection reconstruction as well as for iterative reconstruction algorithms. The implication is that not only is Time of Flight (TOF) reconstruction more advantageous for large patients, but also that the improvement is higher for PET scans performed at higher count rates, compared to a conventional non-TOF reconstruction

Improvement in Signal-to-Noise-Ratio at variable Random Fraction in TOF PET

Time of Flight (TOF) Positron Emission Tomography (PET) produces an improvement in signal-to-noise ratio (SNR) over conventional non-TOF reconstruction. This improvement increases with the size of the patient and with better coincidence time resolution of the system. As a first approximation in TOF PET reconstruction, this gain in SNR is independent of the scatter and random components of the total signal. On the other hand, recently a model has been proposed in which the SNR gain of TOF PET vs. conventional PET is a growing function of the random events fraction. This would provide an additional advantage of TOF PET reconstruction over conventional PET, particularly in the presence of a large random fraction. In this work we show measurements on a NEMA image quality phantom on a Siemens Biograph mCT TOF PET/CT scanner, which confirms the prediction of the model for filtered back projection reconstruction algorithms, in the case of a non uniform source distribution. The implication is that not only is TOF reconstruction more advantageous for large patients, but also the improvement is higher for PET scans performed at higher count rates, compared to a conventional non-TOF reconstruction

Ocular manifestations in thalassemia minor.

The authors report the results of a study on 96 subjects affected with thalassemia minor. The study was made at the Center for the Study of Microcythemia of the OORR in Naples. Of extreme scientific interest is the finding of ocular involvement in 33.3% of the cases. Therefore, after formulating a pathogenetic hypothesis, the authors plan more involved studies and research on these patients