Detection of calcium by the nanosecond time-gated spectroscopy of plume in laser ablation of biological tissue and its application to clinical diagnoses

我们提出了纳秒时间选通光谱的羽激光烧蚀生物组织，并建议这种特定的光谱是有用的骨质疏松症的筛查和日常监测的钙摄入量。在此基础上，我们提出了微米级的光学诊断和手术，包括有效的诊断和切除钙化的恶性肿瘤。(1)提出了组织消融羽流的纳秒时间选通光谱技术。研制了一套高灵敏度的钙离子检测光谱系统样机。(2)对从婴儿到90岁的几十个年龄段的女性头发样品进行了钙峰强度的测定。Ca峰值强度在15岁左右达到最大值，之后逐渐下降。另一方面，我们没有认识到男性头发的Ca峰强度随年龄的急剧变化。(3)发现钙峰强度与测量值有很好的相关性。 关于我们 用双能X线骨密度仪（DEXA）测定骨密度的艾德值，表明我们的特异性光谱法适用于骨质疏松症的筛查。(4)对正常饮食和缺钙饮食大鼠的指甲进行钙检测。钙缺乏大鼠10周龄后钙峰强度明显降低。而去卵巢大鼠指甲钙峰强度与对照组相比无明显变化。这一结果表明，我们的方法是有用的，每日钙摄入量的监测。(5)将组织消融技术与光学相干断层扫描技术（OCT）相结合，提出了一种新的微米尺度的光学诊断和手术方法，包括测量皮肤沿着深度的Ca分布和切除钙化的恶性肿瘤，其空间分辨率可达μm量级。(6)实验中，我们测量了大鼠股骨沿着桡骨的钙分布。(7)为了提高光学相干断层扫描的空间分辨率，采用卤素灯作为光源，利用超低相干干涉仪成功实现了1.3μm的高分辨率光学相干断层扫描。少

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