Page 6 - Shimadzu Xctal 5000
P. 6

Dual Observation Method for
                     Absorption and Phase                                                                                               Applications (Phase Images)






                     High-Contrast Observations                                                                                           Mouse (Neonate)
                     by Absorption Images and Phase Images                                                                              This is a sample scan of a mouse (neonate). The internal organs can be observed without a contrast medium by, just
                                                                                                                                        using formalin fixation.
                     A phase image is suited to observations of samples with large density differences.                                                         Head              Heart
                     In contrast, an absorption image is suited to observations of samples with large differences in absorption coefficient.
                     The X-ray absorption coefficient makes it possible to visualize samples with no contrast differences, as long as there
                     are density differences. Using these two observation methods widens the scope of observations by enabling                                  Nasal
                     high-contrast sample observations.                                                                                                         septum
                                                                                                                                                                          Tongue

                                                                                                                                                                Thymus            Gastrointestinal
                      Water and Acrylic                                                                                                                                           tract

                     The density difference is larger than the absorption coefficient difference, enabling high-contrast phase image
                     observations.                                                                                                                                                 Stomach    Liver
                     High-contrast phase image observations are possible if the density difference is approximately 0.2 g/cm³ or larger.
                                                                                                                                                            Cross-Sectional Images (Phase)                     VR Image (Phase)
                                                                                    Acrylic         Water
                                                                                                                                        A single scan with Xctal 5000 provides the internal feature of soft tissues such as tongue, heart, thymus, liver,
                                                                                                                                        stomach,  as well as the clear image of hard tissues equivalent to that scanned by a conventional micro CT system.
                                                                      Absorption
                                                                      Coefficient     0.36           0.38                                The sample remains intact without using contrast enhancing media, enabling users to carry out further histological
                                                                      cm - ¹                                                            analyses immediately.
                                                                                                                                        (Samples and comments provided by: Professor Sachiko Iseki and Shigeru Okuhara, Section of Molecular Craniofacial Embryology and
                                                                      Density        1.19            1                                  Oral Histology, Tokyo Medical and Dental University)
                                                                      g/cm³
                                                                                                                                                                        The affiliation of the providers of the samples and comments is as of November 11, 2022.



                       Cross-Sectional Image  Cross-Sectional Image
                          (Absorption)            (Phase)                                                                                 Insects and Fish

                                                                                                                                        These are sample scans of a robust cicada and twospot hogfish.
                      Water and Multiple Types of Resins

                     The contrast differs for the absorption image and the phase image. As shown in the graphs below, it is evident that
                     the brightness value for the absorption image is proportional to the absorption coefficient, and the brightness value
                     for the phase image is proportional to the density.
                                                                                                                                                                          Cross-Sectional Image (Phase)  VR Image (Phase)
                              PVC                    PVC                        ABS  PVC  PTFE  PE  POM  Water
                        ABS                    ABS                                                                                                                                     Brain          Internal organs
                                  PTFE                   PTFE         Absorption
                                                                      Coefficient   0.29  1.87  0.87  0.26  0.47  0.38
                                                                      cm - ¹
                        POM                   POM                     Density
                               PE                     PE              g/cm³     1.07  1.26  2.17  0.96  1.42  1

                       Cross-Sectional Image  Cross-Sectional Image                                                                           Cross-Sectional Image (Phase)  Cross-Sectional Image (Phase)  Cross-Sectional Image (Phase)
                          (Absorption)            (Phase)
                                                                                                                                        Insects have conventionally been too small for high-resolution CT scans to be performed. In these cross-sectional
                                            PVC
                                                                                                PTFE                                    images, however, the flight muscle bundles running across the thorax of a female robust cicada and individual eggs
                                                                                                                                        packed into the abdomen are clearly visible.
                    Brightness Value a.u.  PE  ABS  POM  PTFE      Brightness Value a.u.  PE  ABS                                       This system is capable of observing the viscera and brains of small vertebrates, such as fishes, morphologically. As a
                                                                                                                                        (Samples and comments provided by: Dr. Shuhei Nomura, Division of Terrestrial Invertebrates, National Museum of Nature and Science)
                                                                                      POM
                                                                                    PVC
                                                                                                                                        result, it is expected to advance progress in the difficult surveys of soft parts. The new observative method does not
                                                                                                                                        require staining, which is important for maintaining precious biological specimens and materials.
                                                                                                                                        (Samples and comments provided by: Dr. Gento Shinohara, Division of Vertebrates, National Museum of Nature and Science)
                                                                                                                                                                            The affiliation of the providers of the samples and comments is as of July 27, 2022.
                     0            1             2            3      0             1            2             3
                                 Absorption Coefficient cm - ¹                        Density g/cm³
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