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International audience; Understanding the dynamic of in-depth migration and retention of hydrogen in Carbon Fiber Composites (CFCs) used as plasma facing material has for long time been complicated by the lack on in situ analyzing tools. A dedicated experimental setup coupling an ECR ion source to the Saclay nuclear microprobe was developed to expose CFC samples to deuterium implantation at 200–300eV and fluences from 1022 to 1024D/m2, and then to perform in situ μNRA analysis for 3D deuterium profiles. Once the technique proven as non perturbative, we observed that while we have a homogeneous, fluence-independent deuterium concentration at the surface, the in-bulk deuterium is concentrated in the porosities and increases with the incident fluence, up to very large depth (500μm). For the first time, it was evidenced that these two distinct mechanisms are simultaneous to the implantation. D profiles evolve very little with in-vacuum storage time.

Since its development in the early 1990’s, ion beam induced charge (IBIC) microscopy has found widespread applications in many microprobe laboratories for the analysis of microelectronic devices, dislocations, semiconductor radiation detectors, semi-insulating materials, high power transistors, charge-coupled arrays, solar cells, light emitting diodes, and in conjunction with Single Event Upset imaging. Several modalities of the techniques have been developed, such as lateral IBIC and time-resolved IBIC. The theoretical model of IBIC generation and collection has developed from a one-dimensional model of charge drift and diffusion to a detailed model of the motion of ion charge carriers in semiconductors and insulators. This paper reviews the current state-of-the-art of IBIC theory and applications.

The increased modularity in the total hip arthroplasty (THA) allows adapting the prosthesis to the specific anatomical characteristics of each patient. However, the advantages of the modular THA are shadowed by the increased number of prosthesis failures observed in patients. The presence of junction in modular THA may increase its risk of mechanical failure. Moreover, the micro movements between neck and stem could lead to the production of metallic debris which may cause tissue inflammation and unsealing of prosthesis due to osseous dissolution. It is necessary to understand the mechanism of dispersion of the metal particles from the prosthesis into the tissue. Techniques currently applied in hospitals, such as X-ray scans or optical tissue microscopies, are able to distinguish metal particles, but unable to identify their specific metallic origin. In this work, within the TissueMaps project, we have proved that Proton Induced X-ray Emission (PIXE) is able to provide the distribution and elemental composition of particles from the prosthesis into the pseudo capsular tissue samples (near the femoral head) and identify the features observed under optical microscopy, in a case of broken neck prosthesis.

Hip prosthesis replacement is one of the most frequent and costly treatments in developed countries. The increased number of patients and the insufficient understanding of physiological processes leading to prosthesis failure make necessary the use of complementary techniques to better understand the degradation of implants [1]. We present two cases of prosthesis failure: Patient 2, with a modular hip prosthesis made of TiAlV alloy (Profemur®), presents a broken neck; and Patient 7, with a Ceramic on Ceramic articulation made of zirconia toughtened alumina (Biolox® Delta), presents a broken acetabular inlay. The presence of metallic debris coming from the prosthesis has been studied by using Particle-Induced X-ray Emission (PIXE). This technique combines high elemental sensitivity (detection limit 0,1 ppm) with high lateral resolution (600 nm) [2]. The analysis was performed with the 2 MV tandem accelerator available at Jožef Stefan Institute (JSI) [3]. [1] Fokter SK, et al., Acta Orthopaedica, 87(2), p.197-202, 2016. [2] P. Vavpetič et al., Nuclear Instruments and Methods in Physics Research B, vol. 306, pp. 140-143, 2013. [3] Primoz Pelicon et al., Nuclear Instruments and Methods in Physics Research B, vol. 332, pp. 229-233, 2014, This project, TISSUEMAPS, has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 799182.

Hip prosthesis replacement is one of the most frequent and costly treatments in developed countries. The increased number of patients and the insufficient understanding of physiological processes leading to prosthesis failure make necessary the use of complementary techniques to better understand the degradation of implants [1]. We present two cases of prosthesis failure: Patient 2, with a modular hip prosthesis made of TiAlV alloy (Profemur®), presents a broken neck; and Patient 7, with a Ceramic on Ceramic articulation made of zirconia toughtened alumina (Biolox® Delta), presents a broken acetabular inlay. The presence of metallic debris coming from the prosthesis has been studied by using Particle-Induced X-ray Emission (PIXE). This technique combines high elemental sensitivity (detection limit 0,1 ppm) with high lateral resolution (600 nm) [2]. The analysis was performed with the 2 MV tandem accelerator available at Jožef Stefan Institute (JSI) [3]. [1] Fokter SK, et al., Acta Orthopaedica, 87(2), p.197-202, 2016. [2] P. Vavpetič et al., Nuclear Instruments and Methods in Physics Research B, vol. 306, pp. 140-143, 2013. [3] Primoz Pelicon et al., Nuclear Instruments and Methods in Physics Research B, vol. 332, pp. 229-233, 2014

The metallic-associated adverse local tissue reactions (ALTR) and events accompanying worn-broken implant materials are still poorly understood on the subcellular and molecular level. Current immunohistochemical techniques lack spatial resolution and chemical sensitivity to investigate causal relations between material and biological response on submicron and even nanoscale. In our study, new insights of titanium alloy debris-tissue interaction were revealed by the implementation of label-free high-resolution correlative microscopy approaches. We have successfully characterized its chemical and biological impact on the periprosthetic tissue obtained at revision surgery of a fractured titanium-alloy modular neck of a patient with hip osteoarthritis. We applied a combination of photon, electron and ion beam micro-spectroscopy techniques, including hybrid optical fluorescence and reflectance micro-spectroscopy, scanning electron microscopy (SEM), Energy dispersive X-ray Spectroscopy (EDS), helium ion microscopy (HIM) and micro-particle-induced X-ray emission (micro-PIXE). Micron-sized wear debris were found as the main cause of the tissue oxidative stress exhibited through lipopigments accumulation in the nearby lysosome. This may explain the indications of chronic inflammation from prior histologic examination. Furthermore, insights on extensive fretting and corrosion of the debris on nm scale and a quantitative measure of significant Al and V release into the tissue together with hydroxyapatite-like layer formation particularly bound to the regions with the highest Al content were revealed. The functional and structural information obtained at molecular and subcellular level contributes to a better understanding of the macroscopic inflammatory processes observed in the tissue level. The established label-free correlative microscopy approach can efficiently be adopted to study any other clinical cases related to ALTR.