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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. [ABSTRACT FROM AUTHOR]

Abstract: 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. [Copyright &y& Elsevier]

Nuclear microprobes typically achieve a demagnification between 20 and 100 by using a single-stage quadrupole multiplet as the probe-forming system. Whilst quadrupole lenses provide the strong field necessary for focusing MeV ions, they also have higher intrinsic spherical and chromatic aberrations, and also higher parasitic aberrations than found in solenoid lenses. Given the fundamentally superior spatial resolution which is attainable using solenoids, their use in a two-stage microprobe system comprising a magnetic quadruplet and a solenoid lens as the first and second demagnifying stages respectively is studied here. Calculated results are compared with a two-stage system comprising two quadruplets and also with an existing single-stage system. [Copyright &y& Elsevier]