STUDY ON THE NON-INVASIVE MEASUREMENT OF OXYGEN CONCENTRATION IN TUMORS BY NEAR-INFRARED LIGHT AND EVALUATION OF ITS OPTICAL CT IMAGING

目得：本研究在不同呼吸条件下对肿瘤血红蛋白（Hb）氧图进行了研究，目的是利用三波长近红外光获得可靠的小鼠肿瘤血红蛋白氧图和脱氧血红蛋白氧图或总血红蛋白氧图和Hb氧图。770 nm、808 nm和854 nm三种半导体脉冲激光器被用作近-红外光源。脉冲激光束通过插入肿瘤表面的光纤导入肿瘤。光通过将12根光纤中的7根光纤置于光源的对侧，引导到条纹照相机上，同时获得7个时间分辨光谱数据。每个波长的12倍7个投影数据用于通过滤波的正投影CT图像重建方法获得氧-和脱氧-HB的图像。然后计算小鼠肿瘤的2饱和Imax。结果：本文用近红外光测定了小鼠在三种呼吸状态下的HBO_2饱和度。肿瘤的HBO_2饱和度在吸入碳素时增高，在无呼吸时降低。该图显示了吸入碳素对总HBO_2及其O_2的影响2肿瘤的血氧饱和度分布.吸氧后肿瘤的血红蛋白体积和血氧饱和度随肿瘤体积的变化.吸氧增加血红蛋白体积对小肿瘤是不利的.吸氧后肿瘤的血氧饱和度随肿瘤体积的变化而变化.吸氧增加血红蛋白体积对小肿瘤是不利的.吸氧后肿瘤的血氧饱和度随肿瘤体积的变化而变化.吸氧后肿瘤的血氧饱和度随肿瘤体积的变化而变化2.肿瘤体积增大，肿瘤饱和度降低，但技术上的进一步改进应能提高分辨率，我们已证明使用近红外技术的可行性。红外光在小鼠肿瘤中的活体血氧饱和度测定

PURPOSE : WE STARTED THE STUDY ON THE HEMOGLOBIN (HB) OXYGEN MAPPING IN TUMORS UNDER VARIOUS CONDITIONS IN BREATHING.THE PURPOSE OF THIS STUDY WAS TO GET A FURTHER DEVELOPMENT USING THREE-WAVELENGTH NEARINFRARED LIGHT TO OBTAIN A RELIABLE OXY-AND DEOXY-HB OR TOTAL HB AND HB O_2 SATURATION MAPPING IN MOUSE TUMOR.M&M : THREE KINDS OF SEMICONDUCTOR PULSE LASER,770NM,808NM AND 854NM,WERE USED AS NEAR-INFRARED LIGHT SOURCES.A PULSE LASER BEAM WAS GUIDE INTO THE TUMOR VIA AN OPTICAL FIBER PUTTING IN THE SURFACE OF THE TUMOR.LIGHT TRANSMITTED THROUGH THE TUMOR WAS DETECTED BY 7 OUT OF 12 OPTICAL FIBERS PLACED ON THE OPPOSITE SIDE FROM THE SOURCE AND GUIDED TO A STREAK CAMERA TO OBTAIN 7 TIME-RESOLVED SPECTRAL DATA SIMULTANEOUSLY.12 TIMES 7 PROJECTION DATA FOR EACH WAVELENGTH WERE USED TO OBTAINED AN IMAGE OF OXY-AND DEOXY-HB DISTRIBUTIONS BY USING A FILTERED BACK-PROJECTION CT IMAGE RECONSTRUCTION METHOD.THE IN VIVO TOTAL HB AND HB O_2 SATURATION IMAGES OF MOUSE TUMOR WERE THEN CALCULATED.RESULTS : IN VIVO HB O_2 SATURATION IMAGES OF MOUSE UNDER THREE BREATHING CONDITIONS COULD BE OBTAINED USING NEAR-INFRARED LIGHT.THE HB O_2 SATURATION OF TUMOR INCREASED BY CARBOGEN INHALATION AND DECREASED BY NO-BREATHING.THE IMAGES EXHIBITED THE EFFECT OF CARBOGEN INHALATION ON TOTAL HB AND ITS O_2 SATURATION DISTRIBUTION FOR TUMORS.THE VARIATION OF HB VOLUME AND HB O_2 SATURATION OF TUMOR AFTER CARBOGEN INHALATION AS A FUNCTION OF TUMOR VOLUME.INCREASING HB VOLUME BY CARBOGEN INHALATION WAS EFFECTIVE TO THE SMALL TUMORS.THE HB O_2 SATURATION OF TUMOR DECREASED BY INCREASING OF THE VOLUME OF TUMOR.ALTHOUGH FURTHER IMPROVEMENT IN THE TECHNIQUE SHOULD RESULT IN BETTER RESOLUTION.WE HAVE DEMONSTRATED THE FEASIBILITY OF USING NEAR-INFRARED LIGHT TO OBTAIN IN VIVO HB O_2 SATURATION IMAGES IN MOUSE TUMOR.