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Massimiliano Povero,1 Antonio Miceli,2,3 Lorenzo Pradelli,1 Matteo Ferrarini,2 Matteo Pinciroli,4 Mattia Glauber2 1AdRes Health Economics and Outcomes Research, Turin, Italy; 2Minimally Invasive Cardiothoracic Department, Istituto Clinico Sant’Ambrogio, Gruppo Ospedaliero San Donato, Milan, Italy; 3Bristol Heart Institute, University of Bristol, Bristol, UK; 4LivaNova, Milan, Italy Background: Meta-analyses of studies comparing transcatheter aortic valve implants (TAVIs) and sutureless aortic valve replacement (SU-AVR) show differing effectiveness and safety profiles. The approaches also differ in their surgical cost (including operating room and device).Objective: The objective of this study was to assess the incremental cost-utility of SU-AVR vs TAVIs for the treatment of intermediate- to high-risk patients in the US, Germany, France, Italy, UK, and Australia.Methods: A patient-level simulation compares in-hospital pathways of patients undergoing SU-AVR or TAVIs; later, patient history is modeled at the cohort level. Hospital outcomes for TAVIs reproduce data from recent series; in SU-AVR patients, outcomes are obtained by applying relative efficacy estimates in a recent meta-analysis on 1,462 patients. After discharge, survival depends on the development of paravalvular leak and the need for dialysis. A comprehensive third-party payer perspective encompassing both in-hospital and long-term costs was adopted.Results: Due to lower in-hospital (4.1% vs 7.0%) and overall mortality, patients treated with SU-AVR are expected to live an average of 1.25 years more compared with those undergoing TAVIs, with a mean gain of 1.14 quality-adjusted life-years. Both in-hospital and long-term costs were lower for SU-AVR than for TAVIs with total savings ranging from $4,158 (France) to $20,930 (US).Conclusion: SU-AVR results dominant when compared to TAVIs in intermediate- to high-risk patients. Both in-hospital and long-term costs are lower for SU-AVR than for TAVI patients, with concomitant significant gains in life expectancy, both raw and adjusted for the quality of life. Keywords: sutureless valve, aortic valve replacement, TAVI, DES model, cost-utility

Carbon-ion beams are increasingly used in the clinical practice for external radiotherapy treatments of deep-seated tumors. At therapeutic energies, carbon ions yield significant secondary products, including neutrons, which may be of concern for the radiation protection of the patient and personnel. We simulated the neutron yield produced by proton and carbon-ion pencil beams impinging on a clinical phantom at three different angles: 15°, 45° and 90°, with respect to the beam axis. We validated the simulated results using the measured response of organic scintillation detectors. We compared the results obtained with FLUKA 2011.2 and MCNPX 2.7.0 based on three different physics models: Bertini, Isabel, and CEM. Over the different ions, energies, and angles, the FLUKA simulation results agree better with the measured data, compared to the MCNPX results. Simulations of carbon ions at low angles exhibit both the highest deviation from measured data and inter-model discrepancy, which is probably due to the different treatment of the pre-equilibrium stage. The reported neutron yield results could help in the comparison of carbon-ion and proton treatments in terms of secondary neutron production for radiation protection applications. [ABSTRACT FROM AUTHOR]

In this article, the in vivo study performed to evaluate the uniformity of biological doses within an hypothetical target volume and calculate the values of relative biological effectiveness (RBE) at different depths in the spread-out Bragg peak (SOBP) of the new CNAO (National Centre for Oncological Hadrontherapy) carbon beams is presented, in the framework of a typical radiobiological beam calibration procedure. The RBE values (relative to 60Co γ rays) of the CNAO active scanning carbon ion beams were determined using jejunal crypt regeneration in mice as biological system at the entrance, centre and distal end of a 6-cm SOBP. The RBE values calculated from the iso-effective doses to reduce crypt survival per circumference to 10, ranged from 1.52 at the middle of the SOBP to 1.75 at the distal position and are in agreement with those previously reported from other carbon ion facilities. In conclusion, this first set of in vivo experiments shows that the CNAO carbon beam is radiobiologically comparable with the NIRS (National Institute of Radiological Sciences, Chiba, Japan) and GSI (Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany) ones. [ABSTRACT FROM AUTHOR]

In this paper, the evaluation of the dosimetric capability of a detector based on a CR-39 solid-state nuclear track detector coupled to a 1 cm thickness of PMMA radiator was made with the aim of understanding the applicability of this technique to personal and environmental neutron dosimetry. The dosemeter has been exposed to monoenergetic and quasi-monoenergetic neutron beams at PTB in Braunschweig, Germany and at Ithemba Laboratories, in Faure, South Africa, with peak energies ranging from 0.565 to 100 MeV. The results showed a response that is almost independent of the neutron energy in the whole energy range. [ABSTRACT FROM AUTHOR]

Within the framework of the EURADOS Working Group 11, a comparison of passive neutron dosemeters in high-energy neutron fields was organised in 2011. The aim of the exercise was to evaluate the response of poly-allyl-glycol-carbonate neutron dosemeters from various European dosimetry laboratories to high-energy neutron fields. Irradiations were performed at the iThemba LABS facility in South Africa with neutrons having energies up to 66 and 100 MeV. [ABSTRACT FROM AUTHOR]

LUPIN-II is an upgraded version of LUPIN, a novel rem counter first developed in 2010 specifically conceived to work in pulsed neutron fields (PNFs). The new version introduces some modifications that improve the performance of the detector, in particular extending its upper detection limit in PNFs. This paper discusses the characteristics and the performance of the instrument. Measurements have been carried out in radiation fields characterized by very different conditions: the detector has first been exposed in PNFs with intensity up to 5 μSv per burst, where it could keep the H*(10) underestimation below 20% up to 500 nSv per burst. It has then been tested in operational conditions around particle accelerators, where it has shown performances similar to that of ionization chambers. Its proper functioning has also been verified in high energy mixed fields, where the experimental results matched the Monte Carlo predictions. Its neutron/photon discrimination capability has been tested in a steady-state photon field where, via an innovative technique based on a threshold set on the derivative of the current signal, it was capable of rejecting a photon H*(10) rate of about 25 mSv/h, and in a mixed neutron/photon field, where a time-based discrimination method was employed. [ABSTRACT FROM AUTHOR]

Abstract: A number of studies focused in the last decades on the development of survey meters to be used in pulsed radiation fields. This is a topic attracting widespread interest for applications such as radiation protection and beam diagnostics in accelerators. This paper describes a new instrument specifically conceived for applications in pulsed neutron fields (PNF). The detector, called LUPIN, is a rem counter type instrument consisting of a 3He proportional counter placed inside a spherical moderator. It works in current mode with a front-end electronics consisting of a current–voltage logarithmic amplifier, whose output signal is acquired with an ADC and processed on a PC. This alternative signal processing allows the instrument to be used in PNF without being affected by saturation effects. Moreover, it has a measurement capability ranging over many orders of burst intensity. Despite the fact that it works in current mode, it can measure a single neutron interaction. The LUPIN was first calibrated in CERN''s calibration laboratory with a PuBe source. Measurements were carried out under various experimental conditions at the Helmholtz-Zentrum in Berlin, in the stray field at various locations of the CERN Proton Synchrotron complex and around a radiotherapy linear accelerator at the S. Raffaele hospital in Milan. The detector can withstand single bursts with values of H⁎(10) up to 16nSv/burst without showing any saturation effect. It efficiently works in pulsed stray fields, where a conventional rem-counter underestimates by a factor of 2. It is also able to reject the very intense and pulsed photon contribution that often accompanies the neutron field with good reliability. [Copyright &y& Elsevier]

Abstract: SSNTDs (solid-state nuclear track detectors), primarily made from PADC (poly(allyl diglycol carbonate)), are attractive detectors for dosimetric purposes. SSNTDs are more similar to human tissue than other passive detectors and the measurement of the track parameters provides information about the energy deposition of the incident particle. This paper describes a method for LET measurement based on the measurements of the major and minor axes of the track opening. The method was experimentally tested using alpha particles with energies ranging from 4.2MeV to 6MeV. The experimental results show that PADC can measure the total energy lost by a particle along a path of length Δx divided by the length itself, a quantity strictly related to the LET. [Copyright &y& Elsevier]

Abstract: The paper describes the evaluation of the performances of an innovative neutron spectrometer based on a CR39 SSNTD (Solid State Nuclear Track Detector) coupled to a polyethylene radiator and an aluminum degrader. The spectrometer was experimentally characterized in a previous paper, in this work the interest focuses on the unfolding capability. The evaluation is performed using both simulated and experimental input data. The unfolding code used is based on the well-known Gravel algorithm. The results are encouraging and show an acceptably good spectrometric capability in the neutron energy range from 100keV to 10MeV. [Copyright &y& Elsevier]

Abstract: The double differential particle yield produced by hadron beams striking thick targets of copper, tungsten and ICRU tissue, have been determined by means of the Monte Carlo transport code FLUKA (version FLUKA 2008.3b.1). 400MeV/u carbon ion and 250MeV proton pencil beams have been considered. Secondary neutrons, photons, and protons have been scored. In order to validate the obtained data, a few simulations have been also repeated with MCNPX 2.6.0. The calculated results are presented and compared with the experimental data reported in literature. They should be very useful to solve a number of problems related to technological aspects of hadrontherapy. [Copyright &y& Elsevier]

Objective: The outcome of advanced ovarian cancer patients has not significantly improved since the introduction of platinum. One of the major reasons for this failure is the lack of an effective second-line treatment. In this phase II trial we tested the combination of gemcitabine and etoposide in 2 different groups of patients. Group 1 consisted of patients showing disease progression or relapse within 6 months of first-line platinum-based chemotherapy. Group 2 comprised heavily pretreated patients showing progression during the last chemotherapy attempt. Methods: Thirty-four patients were enrolled. Gemcitabine was administered at a dose of 1,000 mg/m2 on days 1 and 8 and etoposide was administered orally at 100 mg/day on days 8-12 for 6 courses. Results: Eighteen patients (52.9%) had an objective response and the median duration of the response was 10.3 months. Our chemotherapy regimen showed a low toxicity and good patient compliance. In 5 patients the treatment had to be delayed and in only 2 patients it was discontinued. Conclusions: The combination of gemcitabine and oral etoposide seems to be a safe and effective second-line treatment for platinum-resistant ovarian cancer patients. Additional data on larger series are warranted to better define the activity of this combination regimen. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]