Development of fluorescent x-ray CT with synchrotron radiation

Fluorescent X射线技术通常被用于评估在图片的顺序中的特定元素含量非常低，因此测量必须在物体的表面上进行性能。然后，作为一个生物样本，该物种需要将其切割成薄片，并用一束永久性的光束扫描到其表面。荧光X射线计算机断层扫描（FXCT），它可以揭示物体内部元素的分布，而不需要特定的准备，已经得到开发。特别是将X射线探测器定位在90 °光束上，使同步加速器X射线（SR）的线性极化有助于显著地减少化合物散射重叠KI-D2 α-D2射线，从而提高对元素的最小检测能力。使用具有高效率和高计数能力和高精确度的X射线准直仪系统的探测器，我们将FXCT应用于十个微米的高空间分辨率，FXCT应用于降低甲状腺激素中的交叉部门分布，体外，0.1 mm x 0.1 mm x 0.1 mm x 0.1 mm切片厚度或0.025 mm x 0.025 mm切片厚度。FXCT with SR could clearly visualize the 0.005 mg/ml iodine solution in the 10-mm diameter 3-hole phantom at 0.1 x 0.1 mm D12 spatial resolution with 0.1 mm slice thickness。对0.005 mg/ml碘代素溶液的观察，其测量的voxel中的异常碘含量约为5 pg （0.005 mg/ml x1.0 x10-D1-6碘D1 ml）。在甲状腺癌中， FXCT揭示了癌症的一部分，它的含量很高，另一部分的含量很低。它的范围从0.09毫克/克到0.005毫克/克不等，FXCT可以通过选择KI-D2 α-D2荧光X射线线获得特定元素的图像，还有许多其他元素如锌和铜的酶功能，以及癌症治疗的铂可以量化地被想象出来。

Fluorescent x-ray technique is usually used to evaluate very low contents of specific elements in the order of picograms, however the measurement must be performed in the surface of object. Then for biological sample, the specimen is required to be cut into thin slices and scanned with a beam perpendicular to its surface. The fluorescent x-ray computed tomography (FXCT), which can reveal the distribution of inner element of object and do not require the specific preparation, have being developed. Especially by positioning the x-ray detector at 90゜ to the beam, the linear polarization of synchrotron x-rays (SR) helps to significantly reduce the Compton scattering overlapping the KィイD2αィエD2 line and thus improving the minimal detectability of elements. Using a detector with high efficiency and high count-rate capability and highly precise x-ray collimator system, we implemented FXCT with high spatial resolution in the order of tens of micrometers.FXCT was applied to depict the cross sectional distribution of iodine in the thyroid gland, in vitro, at the spatial resolution of 0.1 mm x 0.1 mm with 0.1-mm slice thickness or of 0.025 mm x 0.025 mm with 0.025 mm slice thickness. FXCT with SR could clearly visualize the 0.005 mg/ml iodine solution in the 10-mm diameter 3-hole phantom at 0.1 x 0.1 mmィイD12ィエD1 spatial resolution with 0.1 mm slice thickness. Observation of the 0.005 mg/ml iodine solution indicated that the excited iodine content in the measured voxel is about 5 pg (0.005 mg/ml x 1.0 x 10ィイD1-6ィエD1 ml). In the thyroid cancer, FXCT revealed that a part of cancer had high content of iodine, whereas another part had low content of iodine. It varied wide ranges from 0.09 mg/g to 0.005mg/g.FXCT can obtain the image of specific elements by selecting the KィイD2αィエD2 fluorescent x-ray line, so many other elements such as zinc and cupper for enzyme function of tumor, and platinum for the cancer therapy will be imaged quantitatively.