Co-Investigator(Kenkyū-buntansha) |
OHMI Masato Osaka University, Faculty of Medicine, Research Associate, 医学部, 助手 (60273645)
MORIMOTO Shigeto Osaka University, Graduate School of Medicine, Assistant Professor, 大学院・医学系研究科, 助教授 (20150336)
|
Research Abstract |
We proposed nanosecond time-gated spectroscopy of plume in laser ablation of biological tissue, and suggested that this specific spectroscopy is useful for screening of osteoporosis and daily monitoring of Ca intake. On the basis of the research results, we have proposed micrometer-scale optical diagnoses and surgeries including effective diagnosis and removal of calcified malignant tumors. (1) We proposed the nanosecond time-gated spectroscopy of plume in tissue ablation. A prototype of spectroscopy system was developed to perform highly sensitive detection of calcium. (2) The Ca peak intensity was measured for several tens of hair samples of female over a wide range of age from infant to 90 years old. The Ca peak intensity became maximum around 15 years old, and then it decreased gradually. On the other hand, we did not recognize such a drastic change of the Ca peak intensity with age for male hairs. (3) It was found that there was a good relation of the Ca peak intensity and the measur
… More
ed value of bone mineral density with the dual-energy X-ray absorptiometry (DEXA), showing that our specific spectroscopy is applicable for screening of osteoporosis. (4) Ca detection was made for nail of rats with normal diet and Ca-deficient diet. Remarkable reduction of the Ca peak intensity was found for the Ca-deficient rats after ten-weeks old. On the contrary, there was no remarkable change of the Ca peak intensity of nail for ovariectomized rats, compared to that of control rats. This result suggested that our method is useful for monitor of daily Ca intake. (5) A new type of optical diagnosis and surgery with micrometer scale was proposed by combination of tissue ablation and optical coherence tomography (OCT), including measurement of Ca distribution along the skin depth and remove of calcified malignant tumor with the spatial resolution of the order of μm. (6) In the experiment, we measured Ca distribution along the radius for rat femur. (7) In order to improve the spatial resolution, high-resolution OCT of 1.3μm was successfully demonstrated using a ultra-low coherence interferometer where a halogen lamp was used as the light source. Less
|