In biomedical application study using phase contrast X-ray, both sample thickness or density and absorption difference
are very important factors in aspects of contrast enhancement. We present experimental evidence that synchrotron hard
X-ray are suitable for radiological imaging of biological samples down to the cellular level. We investigated the potential
of refractive index radiology using un-monochromatized synchrotron hard X-rays for the imaging of cell and tissue in
various diseases.
Material had been adopted various medical field, such as apoE knockout mouse in cardiologic field, specimen from renal
and prostatic carcinoma patient in urology, basal cell epithelioma in dermatology, brain tissue from autosy sample of
pakinson's disease, artificially induced artilrtis tissue from rabbits and extracted tooth from patients of crack tooth
syndrome. Formalin and paraffin fixed tissue blocks were cut in 3 mm thickness for the X-ray radiographic imaging.
From adjacent areas, 4 μm thickness sections were also prepared for hematoxylin-eosin staining. Radiographic images of
dissected tissues were obtained using the hard X-rays from the 7B2 beamline of the Pohang Light Source (PLS). The
technique used for the study was the phase contrast images were compared with the optical microscopic images of
corresponding histological slides. Radiographic images of various diseased tissues showed clear histological details of
organelles in normal tissues. Most of cancerous lesions were well differentiated from adjacent normal tissues and
detailed histological features of each tumor were clearly identified. Also normal microstructures were identifiable by the
phase contrast imaging. Tissue in cancer or other disease showed clearly different findings from those of surrounding
normal tissue. For the first time we successfully demonstrated that synchrotron hard X-rays can be used for radiological
imaging of relatively thick tissue samples with great histological details.
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