Observation of Granulation Tissue of Tongue Using Synchrotron Radiation

Abstract

Current imaging technology used in the medical field enables non-invasive observation of body tissues from the body surface. However, this method cannot depict the fine internal structure of tissues at high resolution, and in particular, it can be difficult to visualize granulation tissue without the use of contrast agents. Phase-contrast imaging, a new imaging method that has been actively investigated since the early 2000s, enables visualization of the phase shift of X-rays transmitted through matter. It emphasizes the components of scattering and refraction that occur when X-rays pass through a sample and is approximately 1,000 times more sensitive than absorption-contrast X-ray imaging for observing the fine structure of granulation tissue of the tongue. In the present study, the authors used an X-ray phase-contrast imaging technique termed the diffraction enhancement method to acquire absorption images, refraction-angle images, and ultra-small angle X-ray scattering images of paraffin-embedded granulation tissue of the tongue. The results showed that even in samples with almost uniformly homogenized density due to paraffin embedding, clear images of internal structures could be obtained using synchrotron radiation and perfect crystals, and that visualization of granulation tissue appears possible depending on the sample preparation and irradiation conditions. These findings suggest that explicit images and three-dimensional structures obtained by phase-contrast imaging could potentially provide valuable information towards the evolution of diagnostic imaging techniques and the formulation of treatment plans, and that phase-contrast imaging is an important advancement in the medical field.