Are human peripheral nerves sensitive to X-ray imaging?

Diagnostic imaging techniques play an important role in assessing the exact location, cause, and extent of a nerve lesion, thus allowing clinicians to diagnose and manage more effectively a variety of pathological conditions, such as entrapment syndromes, traumatic injuries, and space-occupying lesions. Ultrasound and nuclear magnetic resonance imaging are becoming useful methods for this purpose, but they still lack spatial resolution. In this regard, recent phase contrast x-ray imaging experiments of peripheral nerve allowed the visualization of each nerve fiber surrounded by its myelin sheath as clearly as optical microscopy.

High-quality quartz single crystals for high-energy-resolution inelastic X-ray scattering analyzers.

Spherical analyzers are well known instruments for inelastic X-ray scattering (IXS) experiments. High-resolution IXS experiments almost always use Si single crystals as monochromators and spherical analyzers. At higher energies (>20 keV) Si shows a high energy resolution (<10 meV), at an exact symmetric back-diffraction condition, since the energy resolution is given by the real part of the susceptibility or polarizability.

Synchrotron X-ray tests of an L-shaped laterally graded multilayer mirror for the analyzer system of the ultra-high-resolution IXS spectrometer at NSLS-II.

Characterization and testing of an L-shaped laterally graded multilayer mirror are presented. This mirror is designed as a two-dimensional collimating optics for the analyzer system of the ultra-high-resolution inelastic X-ray scattering (IXS) spectrometer at National Synchrotron Light Source II (NSLS-II). The characterization includes point-to-point reflectivity measurements, lattice parameter determination and mirror metrology (figure, slope error and roughness).

Tracing X-rays through an L-shaped laterally graded multilayer mirror: a synchrotron application.

A theoretical model to trace X-rays through an L-shaped (nested or Montel Kirkpatrick-Baez mirrors) laterally graded multilayer mirror to be used in a synchrotron application is presented. The model includes source parameters (size and divergence), mirror figure (parabolic and elliptic), multilayer parameters (reflectivity, which depends on layer material, thickness and number of layers) and figure errors (slope error, roughness, layer thickness fluctuation Deltad/d and imperfection in the corners). The model was implemented through MATLAB/OCTAVE scripts, and was employed to study the performance of a multilayer mirror designed for the analyzer system of an ultrahigh-resolution inelastic X-ray scattering spectrometer at National Synchrotron Light Source II.

Synchrotron X-ray imaging via ultra-small-angle scattering: principles of quantitative analysis and application in studying bone integration to synthetic grafting materials.

Optimized experimental conditions for extracting accurate information at subpixel length scales from analyzer-based X-ray imaging were obtained and applied to investigate bone regeneration by means of synthetic beta-TCP grafting materials in a rat calvaria model. The results showed a 30% growth in the particulate size due to bone ongrowth/ingrowth within the critical size defect over a 1-month healing period.

Long and compact x-ray pathway for experiments requiring high coherent x-ray beams.

A long x-ray pathway based on an x-ray back-diffraction cavity for coherent x-ray beam experiments is presented. In the present work, such a setup was tested and used for propagation-based x-ray phase contrast imaging (PBI). This setup showed to be useful for PBI purposes, with the advantage of being compact (3 m long) when compared with long x-ray synchrotron beamlines with dimensions from tens to hundreds of meters.

Quantitative and qualitative studies on high-contrast X-ray radiography with an asymmetrical crystal set-up at Elettra.

An analyzer-based X-ray phase contrast imaging (ABI) system with an asymmetrical crystal set-up was mounted at Elettra's SYRMEP beamline. It was the first time that this set-up was implemented at Elettra. Advantages and disadvantages of such a set-up were exploited with quantitative and qualitative studies.

Diamond thermal expansion measurement using transmitted X-ray back-diffraction.

The linear thermal expansion coefficient of diamond has been measured using forward-diffracted profiles in X-ray backscattering. This experimental technique is presented as an alternative way of measuring thermal expansion coefficients of solids in the high-resolution Bragg backscattering geometry without the intrinsic difficulty of detecting the reflected beam. The temperature dependence of the lattice parameter is obtained from the high sensitivity of the transmitted profiles to the Bragg angle variation with temperature.